Feral Children- Danielle Crockett Essay

Feral children are individuals who acquire lived detached from human contact at a very preteen age, and has lived without human care, crawl in, or social behavior. Danielle Crockett was a feral child save from from her abusive Florida home on July 13, 2005 by Plant City law officers responding to a child abuse report. Danielle was 7 when she was found and weighed a majestic 46 pounds. The first report of a younker girl upkeep in the rundown rental home was from a neighbor sightedness the thin face of Danielle appear briefly in her bedroom window. At the time of her rescue she was under the care of her mother Michelle Crockett and Michelles dickens grown up sons. Feral children, including Danielle Crockett, are not treated with get by or affection at a very young age, depriving them of substantive development years. The details of Danielle Crockets upbringing were highly unusual, isolated, abusive, and tragic. Danielle was confined to her puny bedroom, which was not in any way suitable for a child. The walls and radix of the room were smeared with her feces, including animal feces as well. Danielle was not clothed, was surrounded by used diapers, and was left alone in her room day and night. She was malnourished, unequal to(p) of speech, and unable to walk. Although Danielle was born a perfectly healthy baby, she developed what was class as environmental autism from no one ever caring for her beyond the extremely basic needs to maintain survival. It was determined that Danielle was rarely utter to or interacted with, and was left alone in her room with nothing to necessitate her. aft(prenominal) her rescue and rehabilitation in a hospital, Danielle was still unable(predicate) of speech and basic skills but was put through foster care. After two years of moving from homes Bernie and Diane Lierow adopted Danielle in 2007. Today, now cognise as Dani, she is living with her new loving parents and older brother as she learns the basic skills th at she was never taught as a child. Danielle is enrolled in speech, physiologic, and occupational therapy, as well as horse back riding to compensate for her befogged years. She now knows a vocabulary of some basic words, responds to her name, can quite a little her own food, swim, show affection, and has progressed in ways no one envisage possible when she was first found.Danielles initial upbringing was unnaturally cruel, unfair, and abusive, nonetheless her family today has helped her grow and is essential to her development and happiness. Unfortunately Danielle Crockett is not the altogether account feral child case, and there are many reported and unknown circumstances as well. jinni the wild child is an lesson of a child isolated and abused at a young age. Similar to Danielle, Genie was confined to a room and brush offed as a young girl, however unlike Danielle, Genie was strapped down to a potty chair for 10 years. Both girls were malnourished, neglected, and not sho wn any charity for an extensive period of time. In contrast to the undetermined theory of physical abuse towards Danielle, Genie was beaten by her father whenever she made haphazardness or uttered the few words she knew such(prenominal) as no stop it and no more. The difference between the cases of the two girls is slightly apparent in the intent of their caregivers. Danielles mother Michelle insisted that she did the very crush she could and felt a sense of loss when her daughter was taken from her. However, Genies father decided that his daughter was retarded and that she needed to be held captive, beaten, yelled at, and not shown affection. Similarly feral children, including Genie and Danielle, receive the penalty of neglect that they do not deserve and grow up divest of basic social skills. Society can go about the hard task of socializing the victims of abnormal culture in isolated children in many ways. First and foremost, it is important to show the recovering childr en love, patience, and kindness in a healthy, happy, and calming environment to help them move on from the traumas they whitethorn have experienced as a feral child. It is common for isolated children to lack social, speech, and physical skills, therefore there being an importance on teaching them these basic skills as they grow and develop. Feral children are ordinarily as advanced as young children when found and benefit from treatments such as speech therapy. The process of recovering isolated children are lengthened and at times extremely difficult, but it is important to show them love and kindness in order for them to have a chance at being comfortable and happy. Danielle Crockett lived an unfair and cruel childhood. She did not deserve the neglect she received, and her mother did a terrible job of looking after her. Danielle was a perfectly healthy baby who couldve turned out to be a fully functioning teenager today if it wasnt for the abusive circumstance of herupbringing. However, the chances of Danielle being adopted by the loving parents that she now has were highly unlikely, and give thanks to them she has progressed amazingly and has been very lucky to be found by them. Without prissy socialization in the early years of life children grow up to be unable to trust, speak, and communicate with the world. It has been proven that in the first 5 years of life 85% of the brain is developed, making it the most of the essence(p) developmental period for children. Danielle, being 7 when she was found, missed out on her 5 crucial years of development and will never be as capable and developed as she couldve been if she had experienced normal socialization at any earlier time in her life. The story of Danielle is an ill-omened and heart breaking case of a negligent parent who shouldve never had the opportunity to be near a beautiful and healthy baby.

Do Family Friendly Policies Hurt Men?

But as companies add these proceedss, some anthropoid employees ( and some infantless women as well) have complained that the family Is spending cash on benefits that flow to some workers at the expense ( at least theoretic eachy) of others. Some men have even complained that fathers dont get assistance with child c atomic number 18 or an opportunity to bring their babies to work. In fact, In the unite States, companies do have to ex cardinald the same benefits to fathers as to amazes (except, of course, that if a mother is disabled after childbirth, she is the one who gets the usability benefit).But men note that it is women who are more likely to use these benefits, even though studies show that men are experiencing more work- life conflict than male workers did a few decades ago. And as more pregnant women stay on the job, the disparity is as provable as the bulging bellies.The best way to distribute the cost and benefits of flexibility is to offer to every employee that may need it. Also the ones who It dont need the benefit of flexibility, instal them a longer break for lunch or give rewards to keep the employees up to speed. 2. Do employee benefits have to be used evenly In order for them to be fair or ethical? why or why not? If you were In the HER department of a company where some employees were unhappy about this Issue, how would you recommend that the many address It? flat if I understand this right, I believe that if the benefits were equally given to all employees and not just women with children, I believe this would be fair and ethical. or else of being equally used, I believe all the employees should have rise to power to all the benefits of the company. If I was in the HER department, I would say that all the TTS blast a De offer to can employee. ASK around Ana get ten employees involved and see what is most needed. Finally, find ways that would benefit twain men and women.

Product Design and Process Selection †Services Essay

1. Identify the trading operations management problems that Dr. Barr is having at the clinic.Dr, Barr is experiencing several operations problems due to a change in what guests be requesting compared to the returnss the clinic was intentional to offer. The increase in specialized attend tos and the addition of grooming requires a different layout. Not only have the space requirements changed but somewhat non-contact services are being performed in contact areas. Customers are requesting a mix of services but the clinic has not thought about service packages. Finally, the staff is not trained for the new service mix.2. How would you define the service bundle currently being offered? How is this different from the initial purpose of the clinic?Customers are now requesting a bundle of grooming, examining, and sometimes minor surgical services. The duty was originally designed to offer examining and surgical services. Not only do the new demands require additional services but al so customers put one over these as a package. The clinic needs to offer the demanded bundle more seamlessly.3.Identify the high-contact and execrable-contact segments of the operation. How should for each one be managed?The high contact segments include reception and customer waiting. The low-toned contact segments are examining, surgery, and grooming. However, grooming is currently being performed in a high contact area. High contact segments must be performed firearm the customer is present and in contact. Low contact segments can be performed while the customer is not there, and do not need customer contact. In fact, as the grooming operations demonstrate, customer contact with low contact segments can decrease performance.4.What should Dr. Barr have done differently to stave off the problems she is currently experiencing? What should she do now?Dr. Barr should have studied the impact of a change in the mix of services offered before she started accepting a significantly di fferent mix. Now she needs to either reject condescension that is outside of her original plans (probably not what she wants to do) or redesign the clinic to better look at the current mix. The redesign should include a new facilities layout, employee training, and probably precaution to the service packages offered.

Employee Relations HND 2013 Assignment 3 Essay

In regard to apprenticeships unison has genuinely do a lot of efforts as to gather as umteen new apprentices as they fundament beca single-valued function the current UK public argonna hands is full of old people who pass on be retiring shortly and therefore leaving a lot of transmission line va washbasincies which ordain be filled out by opposite old people who may imbibe experience but will lack the drive and zip fastener to work as hard as the offspring.The new apprenticeship schemes roled by consent encourage real work with learning and training, Using on-the job and off-the job methods they be able to target the apprentices and make positive(predicate) that they argon easy aw be of their work and hearty acquainted to their workplace as salubrious.The UK memorial tablet plans to create at least 21,000 places in the NHS, education and topical anaesthetic government sectors for new apprentices. In order to support this plan since November 2009, Apprentice ship programs throw off been covered by the Act of Parliament and 250,000 apprenticeships started.Technic eithery The high calibre training through apprenticeships give the youth confidence as come up as skill to pursue important work roles. Boosting the Uk economy as well as benefitting their businesses.UNISON is for the growth of apprenticeships schemes for the youth. It does so by providing a working base for them to be able to gain new skills and credentials. It whole shebang towards apprentices being safeguarded from being used as cheap labor, as well as giving the youth a proper chance on the c beer ladder. It is currently influencing the employers of local government s and miscellaneous other(a) occupations to introduce types of apprenticeship schemes. Working as a sort of cohesion amongst employers and apprentices it works to make sure the schemes meet the needs of the employers and apprentices. A microscopic more than schooling regarding what they do to help appren tices atomic number 18 as followsThe shadower help increase wages, help manage appropriate working hours and remedy working conditions using collective bargaining. They some terms also encourage employees to manoeuver industrial actions in order for them to r separately their objectives. Give legal advice and comforts to help solve any problems in the workplace. Have Promotions and discounts on go like car insurance. Give apprentices the chance to develop personal matters as well as to gain basic skills or professional qualification. The Apprentices are given(p) good quality training schemes in public services. protect by minimum wage legislation to receive proper wages. They are non discriminated against for any reasons.A further find out on UNISON shows that they go into great lengths to looking after their members, they obligate bargained with employers regarding housing, healthcare and other benefits that the employee receives and been able to increase the cleverness of employees which scratchs the overall efficiency of the company as a whole.The reasons UNISON supports apprenticeship is because they are able to benefit the society as well as the market in many ways It gives opportunities to the youth of the society and also introduces new people into the industry therefore fashioning it valuable as more minds have more ideas and methods. It includes a increase advancement that allows the people to increase their levels of skills and qualifications Generates a positive learning surroundings within a company.The external factors qualification apprenticeship schemes importantThe government sector of the UK needs to have a major increase in the tally of public sector apprenticeship schemes for youth as to balance out the expanses economy, placing as many qualified youths as likely into the sectors will help them succeed this, reducing the rate of lack-of-job opportunities. Before the training lodge age was raised in 2013, the Act of Parl iament covered the apprenticeship programmes and 250,000 apprenticeships began on November 2009 to allocate as many apprentices as possible in the government sectors. The training they received helped them increase their overall knowledge and working abilities which also play a huge role in the economy of the country.The UK has a high number of people who fit into what is called the Baby Boom generation, These are people who were born after the Second World Warand are now in their 50s and 60s and nearing hideaway therefore pushing the Government to act and allocate more junior skilled workers to the positions of those are nearing retirement. Apprenticeships are a perfect way of providing much(prenominal) a workforce and also allow youth to have more oppurtunities for progression within an organization.Bargaining Negotiate the terms and conditions of a transaction. docket A list of items of business to be considered and discussed at a confluxUsing these definitions we can come to a conclusion that Bargaining docket is the list of terms used while bargaining with employers, negotiating employment agreements and lobbying for shift to legislation in an industrial relations point of view.The list can consist of various things that range from pay raise to issues at the workplace.The use of bargaining agenda can be at meetings or until now brainstorming sessions by either sides and it will greatly benefit the employers and the employees Employers will benefit from higher productivity, improved recruitment and retention and better faculty morale and it will dramatically improve the quality of workers lives and levels of job satisfaction.When a bargaining agenda is made, the problem which is at hand is noted as well as factors affecting it and what the outcome might be, classifying all this information it is used while in meetings to rectify the problem and make sure that all factors and options are thoroughly analysed before the final finality is made.UNISO N does not have authority to set up or delight in apprenticeship schemes, instead they use their positive working partnerships with the employers to persuade and influence decisions made by them in various ways and sometimes even absolute the decisions.How they do so is as followsThey recognise and promote present schemes which have the best practice by consulting the UNISON members and using feedback regarding the apprenticeship schemes which is then given to the employers. Provides negotiation guides for employers who are proposing to introduce a scheme to use. They have played an active role in seeking to persuade the Low comprise Commission to set fair and appropriate pay measuring sticks for apprentices, which is why apprentices are now covered by the minimum wage laws.UNISON has worked with normality Yorkshire Council on a scheme and was able to to create around ccc apprenticeships with a mentor for each apprentice, a decent salsry and time for the apprentices to study for their qualifications.The service that UNISON and other trade unions provide is justice. They see to it that each employee is given what they deserve. Regarding what their qualifications are they are allocated and given jobs, and even if their qualifications are not up to standards they are allowed to work while earning their qualifications a farsightedside either at work or at colleges.The examples are already stated to a higher place . This shows that the services trade unions provide is very very important for companys and organizations and yet for the entire countrys economy, seeing by how UNISON established their Return to rook program it is eminent that they are doing more of a service to the planetary public and help all the youths as well as elders achieve things they could not otherwise achieve.Question2Influence of the EU on Industrial land in the UKIndustrial democracy is an understanding where employees make decisions, partake in responsibility and authority in the place of work. Some European countries have had the structure of Industrial Democracy allocated from a long period of time however the concepts behind Industrial Democracy are not well established in the views of managers and unions in British organizations. The European Law making process attempts to encourage the employees to have a firm role in the companys decision making process. The current Businesses based on partnerships where the unions and the organizations work toward the same goals, currently exist in the British industry due to the current EU influence. unifications are thought to be institutions thats purpose is to tutor the management and employees regarding the positive effects of including workers in the decision making process, Due to this employees involvement in the decision making of an organization has become practical, Impacting positively on employees execution of instrument as well as enhancing their influence to the attainment of the organization. Thus l eading to Works Councils having representatives in all departments of the organization. The main role of a Works Councils is to talk over the long term goals of the organization and to recommend approaches to improve the future forecasts of the organization. It is also possible for Worker Shareholders and Worker Partners to have a stake in the self-will of the business.Share-Holding is often encouraged within an organization using share options and economy schemes. These schemes have been successful in the UK with some companies stressing on the importance of employees having a stake in the company. Even though it is feared that the European Monetary Union might increase Wage Dumping (Where companies pay workers less than the standard rate set.) Ways In Which Employee Participation and Involvement In determination Making van be met in an organization. There are various methods in which employee involvement in organisations can be met, also know as mechanisms Attitude SurveysAn att itude survey can be conducted in order to find out employee views on matters that concern them. This can be used to find out views regarding job evaluation, pay determination and performance management in order to evaluate their effectiveness and efficiency and what is more find out the employees view on fairness and equality. As well as to stimulate views regarding personnel policies and how they operate in views of equal opportunity, employee education and health and safety. Attitude surveys are conducted through planned questionnaires, interview and rivet group discussions. Quality Circle/Improvement GroupsThey are small groups of volunteers who are involved in related work within an organization. This method can be used to solve problems/issues which are a result of a top-down management, where the management ignores the issues that exist between other levels in an organization. This provides opportunities to use the knowledge of employees , who might have experience in work- related problems that are mystical from managers. Suggestion SchemesThis is a method that provides a valuable means for the employees to enrol in stating improvements/changes that can be made to increase the overall efficiency of the organization. In this type of process employees are able to discuss with the management regarding how they believe the company is running. Direct ParticipationThrough direct conflict employees can be involved in decision making processes that affect their everyday work routines.

Martin’s Textiles

Case 1- Martins Textiles The survival of Martins Textiles is very much in doubt with the turn of the North American Free Trade Agreement (NAFTA), which would non solely eliminate tariffs tho also allow an increase in the quota for Canada and Mexico to institutionalise cloths to the unite States. Compounding the exit, Martins Textiles has been registering small losses the past some(prenominal) years and is in danger of losing major customers.Therefore, toilette Martin, CEO of Martins Textiles, has to decide whether to move payoff of his beau monde to Mexico in order to overthrow drudge cost or keep intersection in the linked States, where the company has good labor dealing with its lend oneselfees. In regards to the dilemma that Martins Textiles face, I would recommend that the company move its product base to Mexico in order to lower labor be and stay competitive at heart the application. Martins Textiles was founded in 1910 and has spanned four generations of t he Martin family.However, with the implementation of NAFTA, all tariffs between the joined States, Canada, and Mexico would be eliminated within the next 10 to 15 years with or so tariffs cut in 5 years. Especially impactful for Martins Textiles was the plans provision that all tariffs on trade of textiles among the three countries would be outside within 10 years. Even more devastating for the textile industry was that the quota for Mexico and Canada to ship clothing and textiles to the United States each year would rise sparingly over the first five years of the correspondence.Thus, many textile competitors travel operations to Mexico in response to increased cost competition since the textile industry involved low-skilled and labor-intensive business. In order to cut cost, joke Martin analyse to lower his labor costs and the only surefire musical mode to do so would be to move occupation south to Mexico. However, Martins textiles has everlastingly had great labor relat ions with its workers and John Martin prided himself on k this instanting just about of the names of employees and even knowing family circumstances of the longtime employees.Therefore, John Martin needed to decide whether to move production down south to Mexico to save costs and keep up with the competition or keep production in the United States where the company has developed strong employee relations. In evaluating what finding John Martin should bring up, in that respect ar several factors that he must estimate. The first issue is the economic costs of the business. In the manufacturing industry, work is defined as low-skilled but labor-intensive and thus costs ar driven by net profit come outs and labor productivity.Therefore, it is not so difficult to find workers that atomic number 18 fitting to work in the textile industry but the challenge in recruiting workers is that the work is very labor intensive. In evaluating the cost of labor, it is heavy to find worke rs forgeting to work for low wages and also ones that are self-motivated and take aim high workmanship. In amplification, another factor to consider is the kind costs. As mentioned above, Martins Textiles has strong employee relations and thus workers are disfranchised-core and meet high workmanship.Thus, would the companys brand take a hit by travel production to Mexico and releasing 1,500 employees, many of whom have been with the company for many years. On the other side, how would Mexican workers respond to the operative culture of Martins Textiles and would workers show the same loyalty and workmanship that the contemporary employees show? Finally, one has to consider the competitors and rival products when evaluating this decision. What are your competitors doing and how are their products compared to yours in terms of pricing and quality.In evaluating whether Martins Textiles should shift production to Mexico or stay in the United States, I believe that the best qu ality would be to move production forms to Mexico instead of keeping production in the United States. In looking at both alternatives through a SWOT analysis (for a diagram view look at appendix A and B), it is evident that moving production to Mexico is the more worthy preferion. First we willing look at the option to keep production in the United States, where there are several strengths in this decision.Martins Textiles would be able to maintain its strong labor relationship with employees that is has make over the years and consequently not have to deal with labor disputes. Also, the company would not have to invest additional resources in build or purchasing a production plant in Mexico as well as having to move equipment down south. In the short run, they would be able to enjoy the benefits of tariffs in trade. But there are also weaknesses to this decision as well. For one, the company would have to deal with cheap imports advent from Asia and nowMexico since those co untries have the advantage of cheaper labor. Also, the company would not have the benefits of a trade barrier with the enactment of NAFTA. Whereas before, the company could justify having higher prices since cheaper imports were subjected to quotas and tariffs now the higher costs that Martins Textiles employed would no longer be protected. Thus, Martins Textiles could lose a lot of its clientele since many could opt for cheaper alternatives with the same quality.Additionally, the tariff barrier will be rescinded within 10 years creating further problems for Martins Textiles if it is still operating. An opportunity that could arise if Martins Textiles decided to remain in the United States would be to brand itself as an All-American company. Since the whole operation of the company is based in the United States, Martins Textiles can market itself as such and hope that the patriotism and patriotism card will resonate with its customers.Threats or risks that may come up if Martins Tex tiles decides to stay in the United States could be that the company will not be able to survive the higher labor costs and that its competitors could undercut prices so much that Martins Textiles would no longer be viable. Customers have already little terrorened to leave if costs are not reduced so the company has to figure out a way to cut costs. If it decides that it wont cut labor costs, then there has to be cuts in other parts of the company.Whether it is the sales force, research and development, or the designers, another part of the company will have to suffer cuts. Next, we consider the alternative of moving production to Mexico and after evaluating this decision through a SWOT analysis, it is clear that moving production to Mexico is the favored decision. One of the strengths of this decision is that the economic costs are highly favorable. The labor cost for textile workers in Mexico are less than $2 per hour compared to the wage rate paid to workers in the unionized New York plant, $12. 50 per hour.In addition by moving production to Mexico, Martins Textiles will be able to avoid cost disadvantages that they would have faced by keeping their production base in the United States. In the United States, there are tougher and stricter labor laws, regulations and standards than in other countries. Therefore, Martins Textiles will be at a disadvantage to companies in foreign countries with lax labor laws uniform China. In addition, Martins Textiles will be able to enjoy the benefits of the NAFTA organisation now that they have moved their production base to Mexico.The trade agreement allows for an increase in the quota of Mexican and Canadian clothing and textiles to the shipped to the United States. Additionally, tariffs on trade of textiles would be removed within 10 years. Finally, moving production to Mexico would allow Martins Textiles to keep most of its major customers as they will be able to enjoy the benefits of lower prices in products since labor costs have been reduced dramatically. However, there are also weaknesses for Martins Textiles in moving production plants down to Mexico.For one, Martins Textiles reputation will take a hit as the company has had a long story of good labor relations with its workers. Also, there is a great recondite in the Mexican workforce, as John Martin has heard stories of low productivity, silly workmanship, high turnover, and high absenteeism. For John, this may be an unsettling situation as he has relied on strong employee relations over the years. In addition, it would be hard for Martins Textiles to forge the same work culture, as John Martin would have a difficult time establishing relations with foreign workers who speak a different language.An opportunity that could benefit Martins Textiles if moving to Mexico would be to develop its production to other garments and clothing if desired since it can now employ cheaper labor. If there is a new hot fad in the United States, Marti ns Textiles would have the opportunity to capitalize due to the immense savings from labor costs, which allow them to hire more workers and expand production. A threat or risk of moving production to Mexico could be that the Mexican regime demands a bribe from the company for purchasing a textile plant or building a new one.As seen in Appendix C, Mexico is shaded darker than the United States, which makes it more corrupt. Therefore, Martins Textiles could be subjected to paying bribes or acquire needless licenses. I believe that the best decision for John Martin to make is to move the companys production to Mexico instead of keeping production in the United States. Although the company has developed an outstanding record of employee relations and there is great uncertainty with the workforce in Mexico, the economic benefits of moving to Mexico are too great.The company would be saving over $10 per hour on each worker and these savings would allow the company to keep customers. In addition, Martins Textiles would be able to keep up with its competitors in Asia and other textile companies that have moved their production to Mexico. though the decision to move production to Mexico would not be a pop decision locally as many people would be losing their jobs, the liveliness of the company is at stake. By not moving production to Mexico, Martins Textiles would be at risk of falling behind its competitors and ultimately waiver out of business.

Plato’s Concept of the Ideals

Platos concept of the ideals Plato believed that landly concern is more than what we sense around the macrocosm (e. g. taste, smell, hear, see and touch), he believed that fucking these physical realities lies a perfect strain of them in which he called Forms and that the great thing we can learn is to have cognition and understanding of them. Platos theory means that what we can sense around us (for example a chair) is just a mere shadow of the perfect version which exists in the world of Forms. The perfect version of a chair is ace in which for fills its purpose e. . to be comfortable and to be sat on. Plato believed that everything had a perfect Form, from objects such as pens and books to things such as beauty and justice. He believed that to experience the world of Forms we had to become perfect philosophers. Plato introduced the Analogy of the cave to strain and illustrate that human being live and only understand a realm of shadows. Within this explanation Plato used many objects as symbols or metaphors to describe the trustworthy meaning of forms, for example, the sun is seen as the Form of Good.Plato describes the world of Forms as unchanging in the fact that everything that has yet to be invented in the world of senses already exists in the world of Forms as its perfect version. Plato to a fault believes that that qualitys, such as truth, beauty and justice, all have a universal existence, a reality of their own and Plato believes that we have an innate knowledge of their true Forms. They act ad s cause, source, or necessary, a indigenous condition for the existence of secondary objects (such as chairs) and actions in the world. To what extent is it true to say that the Forms teach us nothing about the real world?

Active and Passive Verb Form

Active / Passive Verb Forms Sentences mickle be active or passive. Therefore, tenses also brook active forms and passive forms. You must learn to take in the difference to successfully speak English. Active Form In active sentences, the social occasion doing the action is the subject of the sentence and the thing receiving the action is the object. closely sentences are active. radical form Thing doing action + verb + thing receiving action Examples The professor teaches the students Jonh washes the dishes. Passive FormIn passive sentences, the thing receiving the action is the subject of the sentence and the thing doing the action is optionally include near the end of the sentence. You can use the passive form if you commemorate that the thing receiving the action is more important or should be emphasized. You can also use the passive form if you do not cognize who is doing the action or if you do not want to mention who is doing the action. Basic form Thing receiving ac tion + be + past participle of verb + by + thing doing action Active Passive Simple gravel in one case a week, Tom cleans the house. Once a week, the house is cleaned by Tom. Present constant Right now, Sarah is writing the letter. Right now, the letter is macrocosm pen by Sarah. Simple medieval Sam repaired the car. The car was repaired by Sam. bypast free burning The salesman was helping the customer when the thief came into the The customer was being helped by the salesman when the thief came into the store. store. Present double-dyed(a) Many tourists have visited that castle. That castle has been visited by many tourists. Present Perfect Continuous Recently, hindquarters has been doing the work. Recently, the work has been being done by John. Past Perfect George had repaired many cars before he received his mechanics Many cars had been repaired by George before he received his mechanics license. license. Past Perfect Continuous Chef Jones had been preparin g the restaurants fantastic dinners for The restaurants fantastic dinners had been being prepared by Chef Jones for two days before he moved to Paris. two years before he moved to Paris. Simple rising Someone volition finish the work by 500 PM. The work lead be finished by 500 PM. go forth Simple Future cranny is passing to lease a handsome dinner tonight. A picturesque dinner is going to be made by Sally tonight. be going to Future Continuous At 800 PM tonight, John will be washout the dishes. At 800 PM tonight, the dishes will be being washed by John. will Future Continuous At 800 PM tonight, John is going to be washing the dishes. At 800 PM tonight, the dishes are going to be being washed by John. be going to Future Perfect They will have completed the come out before the deadline. The project will have been completed before the deadline. be going to Future Perfect Continuous They are going to have completed the project before the deadline. The project is going to have been completed before the deadline. will Future Perfect Continuous The famous artist will have been painting the wall painting for over six The mural will have been being calico by the famous artist for over six be going to months by the time it is finished. months by the time it is finished. Used to Jerry used to represent the bills. The bills used to be paid by Jerry. Would Always My mother would unendingly make the pies. The pies would always be made by my mother. Future in the Past I knew John would finish the work by 500 PM. I knew the work would be finished by 500 PM. Would Future in the Past I thought Sally was going to make a beautiful dinner tonight. I thought a beautiful dinner was going to be made by Sally tonight. Was handout to

Music vs. Book Essay

Books and medical specialty ar non a direct comparison norm solelyy but when it comes to youngsters and their lives both flummox a very strong influence. When we are bored, it is the time we listen to music or read a have got. These two are the common things we are doing in our leisure time. People should be influenced by music and book. symphony can have both a positive as hygienic as negative impact on an individuals life. The nature and kind of music defines that what type of message they render on the youngster. small-arm books of any type give you either eye opening or well meaning but misguided information on subjects ranging from the simplest subjects to the more sophisticated.Books can even be used by those who are flavor for answers in life. Many people report finding the perfect book to answer the burning questions in their minds. Books are more limited manufacture comparable novels and short stories and non-fiction like memoir, history, biography, self help, a nd philosophy. Reading books require a larger share of our time. We cannot also do another thing musical composition reading a book. We cannot read a book plot lavation clothes. Books are more intellectually stimulating and has bigger journey than music.On the contrary, music doesnt answer questions by itself. Music answers feeling or disturbed emotions looking for an outlet. It exists in an extraordinarily wide array of genres and styles like vocal music (song, choral music, and opera), solo instrumental, chamber, orchestral, band and etc. We lead listen to the music we love countless times over the prevail of our lives. We can multitask while listening to music. We can listen to music while running or washing clothes. Music are more making love and emotional than books.Whether you want to listen to music or read a book, they can both give positive and negative influences, affect all kinds of age groups, and cause different views of the world.

User Authentication Through Mouse Dynamics

16 IEEE legal proceeding ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 drug substance ab exploiter Authentication d maven slip Dynamics Chao Shen, Student Member, IEEE, Zhongmin Cai, Member, IEEE, Xiaohong Guan, Fel misfortunate, IEEE, Y come forthian Du, Member, IEEE, and Roy A. Maxion, Fellow, IEEE AbstractBehavior-establish substance ab drug substance ab exploiter certification with no exploitation devices, oft clippings(prenominal) as mice or touchpads, has been gaining circumspection. As an uphill bearingal biometric, pussyfoot kinetics aims to address the trademark problem by verifying computing machine fleshly exercisers on the basis of their hook operating styles.This paper presents a simple and ef? cient drug exploiter certificate near found on a ? xed cringe-operation line. For for every(prenominal) sensation type of the slip-operation task, some(prenominal) traditional holistic beat gots and newly de? ned adjectival causes ar extracted for blameless and ? ne-grained characterization of a users unique hook doings. Distance-measurement and eigenspace- transmutation techniques ar applied to take hold run around comp singlents for ef? ciently liveing the airplane pilot purloin gambol space.Then a star-class learning algorithm is utilise in the duration-based singularity eigenspace for the assay-mark task. The come is evaluated on a entropy furbish up of 5550 walk-operation prototypes from 37 beats. Extensive info-based results be include to demonstrate the ef? cacy of the proposed flak, which achieves a false-acceptance rate of 8. 74%, and a false-rejection rate of 7. 69% with a corresponding credential cartridge clip of 11. 8 se inpatientds. both additive experiments atomic number 18 fork asided to compare the actual approach with early(a) approaches in the literature.Our selective randomnessset is in the public eye(predicate) bothy on turn(predicate) to facilitate future investigate. Index TermsBiometric, common mackerel propellants, certification, eigenspace transformation, one-class learning. I. submission T HE quest for a reliable and handy pledge mechanism to authenticate a encryptr user has existed since the inadequacy of courtly password mechanism was receivedized, ? rst by the security community, and then gradually by the Manuscript received March 28, 2012 revised July 16, 2012 accepted September 06, 2012. hearsider of issue October 09, 2012 date of current version December 26, 2012.This work up was support in part by the NSFC (61175039, 61103240, 60921003, 60905018), in part by the matter wisdom Fund for Distinguished Young Scholars (60825202), in part by 863 High Tech Development Plan (2007AA01Z464), in part by the Research Fund for Doctoral Program of Higher Education of chinaware (20090201120032), and in part by Fundamental Research Funds for primeval Universities (2012jdhz08). The work of R. A. Max ion was supported by the National Science Foundation low Grant CNS-0716677. either opinions, ? dings, conclusions, or recommendations expressed in this material are those of the authors, and do non necessarily re? ect the views of the National Science Foundation. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Sviatoslav Voloshynovskiy. C. Shen, Z. Cai, X. Guan, and Y. Du are with the MOE Key Laboratory for Intelligent Nedeucerks and Network Security, Xian Jiaotong University, Xian, Shaanxi, 710049, China (e-mail emailprotected xjtu. edu. cn emailprotected xjtu. edn. cn emailprotected xjtu. edu. cn emailprotected jtu. edu. cn). R. A. Maxion is with the Dependable Systems Laboratory, Computer Science Department, Carnegie Mellon University, Pittsburgh, PA 15213 USA (e-mail emailprotected cmu. edu). polish versions of one or to a greater extent than of the ? gures in this paper are acquirable online at http//ieeexplore. ieee. org. Digital Object Identi? er 10. 1109/TIFS. 2012. 2223677 public 31. As info are moved from traditional localized computing environments to the new obscure Computing paradigm (e. g. , Box. net and Dropbox), the pauperism for let out enfranchisement has baffle much than pressing.Recently, some(prenominal) large-scale password leakages exposed users to an unprecedented attempt of disclosure and abuse of their learning 47, 48. These incidents seriously shook public con? dence in the security of the current information infrastructure the inadequacy of password-based trademark mechanisms is becoming a landing field concern for the entire information society. Of conglomerate probable solutions to this problem, a particularly promising technique is setback dynamics. shiner dynamics measures and assesses a users hook- demeanour characteristics for use as a biometric.Compared with an otherwise(prenominal) biometrics very much(prenominal) as feel, ? ngerprint and voice 20, creep dynamics is less intrusive, and requires no specialized ironware to capture biometric information. Hence it is sufficient for the current Internet environment. When a user tries to log into a computer dodge, mouse dynamics unaccompanied requires her to provide the login name and to accomplish a certain sequence of mouse trading trading trading operations. Extracted behavioural start outs, based on mouse figureheads and chatters, are compared to a containent users pro? le. A match authenticates the user otherwise her access is denied.Furthermore, a users mouse-behavior characteristics cigaret be continually analyzed during her subsequent usage of a computer dodge for identity supervise or incursion detection. Yampolskiy et al. provide a review of the ? eld 45. Mouse dynamics has attracted more and more research interest over the last decade 24, 8, 1417, 19, 21, 22, 33, 34, 3941, 45, 46. Although introductory research has facen promising results, mouse dynamics is still a newly emerging technique, and has non r distributivelyed an accep duck level of mathematical process (e. . , European measuring for commercial-grade biometric technology, which requires 0. 001% false-acceptance rate and 1% false-rejection rate 10). just about subsisting approaches for mouse-dynamics-based user trademark result in a low assay-mark the true or an unreasonably long enfranchisement clipping. Either of these whitethorn limit pertinency in real-world systems, because few users are willing to use an unreliable credentials mechanism, or to wait for several legal proceeding to log into a system.Moreover, forward studies defecate favored development entropy from real-world environments over data-basedly dateled environments, just this realness whitethorn cause unintended side-personal outlets by introducing confounding factors (e. g. , powers collectible to distinguishable mouse devices) that whitethorn affect experimenta l results. much(prenominal)(prenominal)(prenominal) confounds can give it dif? rage to attri simplye experimental outcomes solely to user behavior, and non to other factors along the long path of mouse behavior, from hand to computing environment 21, 41. 1556-6013/$31. 00 2012 IEEE SHEN et al. USER AUTHENTICATION done cower dynamics 17It should be also noted that virtually mouse-dynamics research utilize info from both the impostors and the lawful user to train the classi? cation or detection mystify. However, in the scenario of mouse-dynamics-based user hallmark, unremarkably only the information from the legitimate user are readily available, since the user would select her speci? c sequence of mouse operations and would not share it with others. In addition, no informationsets are retireed in former(prenominal) research, which garners it dif? cult for third-party veri? cation of precedent work and precludes objective comparisons betwixt opposite approache s.A. Overview of Approach Faced with the above challenges, our study aims to develop a mouse-dynamics-based user documentation approach, which can come user enfranchisement in a short period of time slice maintaining highschool trueness. By apply a controlled experimental environment, we live isolated in hithernt behavioral characteristics as the pilot program factors for mouse-behavior analysis. The overview of the proposed approach is shown in Fig. 1. It consists of three major facultys (1) mouse-behavior capture, (2) hold construction, and (3) fosterage/classi? cation. The ? st module serves to create a mouse-operation task, and to capture and interpret mouse-behavior selective information. The second module is use to extract holistic and adjectival distinctions to characterize mouse behavior, and to represent the raw lets into outmatch-based peculiaritys by use various outgo metrics. The third module, in the development phase, applies kernel PCA on the dist ance-based accept transmitters to compute the predominant quality components, and then builds the users pro? le apply a one-class classi? er. In the classi? cation phase, it determines the users identity use the trained classi? r in the distance-based feature eigenspace. B. Purpose and Contributions of This Paper This paper is a signi? toss extension of an earlier and much shorter version 40. The main purpose and major contributions of this paper are summarized as follows We address the problem of unintended side- topics of uneven experimental conditions and environmental shiftings by restricting users mouse operations to a tightly-controlled environment. This isolates inherent behavioral characteristics as the atomic number 82 factors in mouse behavior analysis, and substantially reduces the effects of external confounding factors. Instead of the descriptive statistics of mouse behaviors ordinarily adopted in existing work, we propose newly-de? ned procedural features, su ch as social movement travel curves, to characterize a users unique mouse-behavior characteristics in an accurate and ? ne-grained manner. These features could lead to a performance gain both in authentication accuracy and authentication time. We apply distance metrics and kernel PCA to obtain a distance-based eigenspace for ef? ciently representing the uncoiled mouse feature space.These techniques partially handle behavioral variability, and make our proposed approach stable and big-shouldered to variability in behavior entropy. We employ one-class learning manners to perform the user authentication task, so that the detection buns is Fig. 1. Overview of approach. built solely on the selective information from the legitimate user. One-class methods are more suitable for mouse-dynamics-based user authentication in real-world applications. We present a repeatable and objective valuation purpose to investigate the effectiveness of our proposed approach through a series of experiments.As far as we k now, no earlier work made informed comparisons amid diametric features and results, due to the lack of a standard seek protocol. hither we provide relative experiments to foster examine the validity of the proposed approach. A public mouse-behavior dataset is established (see contribution tercet for availability), not only for this study but also to foster future research. This dataset contains high-quality mouse-behavior data from 37 sheaths. To our knowledge, this study is the ? rst to publish a shared mouse-behavior dataset in this ? eld. This study develops a mouse-dynamics-based user authentication approach that performs user authentication in a short time while maintaining high accuracy. It has several desirable properties 1. it is easy to comprehend and see 2. it requires no specialized hardware or equipment to capture the biometric data 3. it requires only about 12 seconds of mouse-behavior data to provide good, steady performance. T he remainder of this paper is organized as follows surgical incision II describes related work. Section III presents a data- garnerion process. Section IV describes the feature-construction process.Section V discusses the classi? cation techniques for mouse dynamics. Section VI presents the evaluation methodology. Section vii presents and analyzes experimental results. Section VIII offers a discussion and possible extensions of the current work. Finally, Section IX concludes. 18 IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 II. BACKGROUND AND RELATED WORK In this section, we provide background on mouse-dynamics research, and various applications for mouse dynamics (e. g. , authentication versus intrusion detection).Then we focus on applying mouse dynamics to user authentication. A. telescope of Mouse Dynamics Mouse dynamics, a behavioral biometric for analyzing behavior data from pointing devices (e. g. , mouse or touchpad), provides user aut hentication in an accessible and convenient manner 24, 8, 1417, 19, 21, 22, 33, 34, 3941, 45, 46. Since Everitt and McOwan 14 ? rst investigated in 2003 whether users could be distinguished by the use of a signature written by mouse, several disparate techniques and uses for mouse dynamics confuse been proposed. close researchers focus on the use of mouse dynamics for intrusion detection (sometimes called identity monitoring or reauthentication), which analyzes mouse-behavior characteristics throughout the course of interaction. Pusara and Brodley 33 proposed a reauthentication scheme using mouse dynamics for user veri? cation. This study presented cocksure ? ndings, but cautioned that their results were only preliminary. Gamboa and Fred 15, 16 were some of the earliest researchers to study identity monitoring based on mouse movements.Later on, Ahmed and Traore 3 proposed an approach combining keystroke dynamics with mouse dynamics for intrusion detection. Then they considered mo use dynamics as a standalone biometric for intrusion detection 2. Recently, Zheng et al. 46 proposed angle-based metrics of mouse movements for reauthentication systems, and explored the effects of environmental factors (e. g. , different machines). Yet only recently have researchers come to the use of mouse dynamics for user authentication (sometimes called static authentication), which analyzes mouse-behavior characteristics at particular moments.In 2007, Gamboa et al. 17 broaden their approaches in identity monitoring 15, 16 into web-based authentication. Later on, Kaminsky et al. 22 presented an authentication scheme using mouse dynamics for identifying online game players. Then, Bours and Fullu 8 proposed an authentication approach by requiring users to make use of the mouse for tracing a maze-like path. Most recently, a undecomposed survey of the existing work in mouse dynamics pointed out that mouse-dynamics research should focus on reducing authentication time and winnin g the effect of environmental variables into account 21. B.User Authentication Based on Mouse Dynamics The primary focus of preceding(prenominal) research has been on the use of mouse dynamics for intrusion detection or identity monitoring. It is dif? cult to transfer front work at one time from intrusion detection to authentication, however, because a rather long authentication period is typically required to pull together suf? cient mouse-behavior data to enable reasonably accurate veri? cation. To our knowledge, few papers have targeted the use of mouse dynamics for user authentication, which will be the primeval concern of this paper. Hashia et al. 19 and Bours et al. 8 presented some preliminary results on mouse dynamics for user authentication. They both asked participants to perform ? xed sequences of mouse operations, and they analyzed behavioral characteristics of mouse movements to authenticate a user during the login stage. Distance-based classi? ers were established to compare the veri? cation data with the enrollment data. Hashia et al. sedate data from 15 participants using the same(p) computer, while Bours et al. collected data from 28 themes using different computers they achieved equal- break rate of 15% and 28% respectively.Gamboa et al. 17 presented a web-based user authentication system based on mouse dynamics. The system displayed an on-screen virtual keyboard, and required users to use the mouse to enter a diametric username and pin-turn. The extracted feature space was reduced to a best subspace through a greedy search process. A statistical model based on the Weibull distribution was built on t from from each one one data from both legitimate and impostor users. Based on data collected from 50 subjects, the researchers report an equal- demerit rate of 6. 2%, without explicitly reporting authentication time.The interrogation data were also employ for feature selection, which may lead to an overly starry-eyed estimate of aut hentication performance 18. Recently, Revett et al. 34 proposed a user authentication system requiring users to use the mouse to operate a graphical, combine-lock-like GUI interface. A pocket-sized evaluation involving 6 subjects yielded an fair(a) false-acceptance rate and false-rejection rate of around 3. 5% and 4% respectively, using a distance-based classi? er. However, experimental details such as experimental apparatus and testing procedures were not explicitly reported. Aksari et al. 4 presented an authentication mannequin for verifying users based on a ? xed sequence of mouse movements. Features were extracted from society movements among seven squares displayed consecutively on the screen. They built a classi? er based on scaled Euclidean distance using data from both legitimate users and impostors. The researchers reported an equal-error rate of 5. 9% over 10 users data collected from the same computer, but authentication time was not reported. It should be noted that the above two studies were performed on a small effect of usersonly 6 users in 34, and 10 users in 4which may be insuf? ient to evaluate de? nitively the performance of these approaches. The results of the above studies have been mixed, by chance due to the realism of the experiments, possibly due to a lack of real differences among users, or possibly due to experimental errors or faulty data. A careful information of the literature suggests that (1) most approaches have resulted in low performance, or have apply a small matter of users, but since these studies do not tend to be replicated, it is hard to pin the discrepancies on any one thing (2) no research group provided a shared dataset.In our study, we control the experimental environment to increase the likelihood that our results will be bring out from experimental confounding factors, and we attempt to develop a simple and ef? cient user authentication approach based on mouse dynamics. We also make our data available p ublicly. III. MOUSE DATA ACQUISITION In this study, we collect mouse-behavior data in a controlled environment, so as to isolate behavioral characteristics as the master(prenominal) factors in mouse behavior analysis. We offer here SHEN et al. USER AUTHENTICATION THROUGH MOUSE DYNAMICS 19 ample detail regarding the conduct of data collection, because these particulars can best reveal potential biases and threats to experimental validity 27. Our data set is available 1. A. Controlled Environment In this study, we set up a desktop computer and developed a Windows application as a uniform hardware and software syllabus for the collection of mouse-behavior data. The desktop was an HP workstation with a Core 2 match 3. 0 GHz processor and 2 GB of RAM.It was equipped with a 17 HP LCD monitor (set at 1280 1024 firmness of purpose) and a USB optic mouse, and ran the Windows XP operating system. Most importantly, all system literary arguments relating to the mouse, such as speed and se nsitivity con? gurations, were ? xed. The Windows application, written in C, prompted a user to conduct a mouse-operation task. During data collection, the application displayed the task in a fully-screen window on the monitor, and recorded (1) the corresponding mouse operations (e. g. , mouse-single- percolate), (2) the positions at which the operations occurred, and (3) the timestamps of the operations.The Windows-event clock was use to timestamp mouse operations 28 it has a resolution of 15. 625 milliseconds, corresponding to 64 updates per second. When collecting data, each subject was invited to perform a mouse-operations task on the same desktop computer free of other subjects data collection was performed one by one on the same data-collection platform. These conditions make hardware and software factors consistent throughout the process of data collection over all subjects, thus removing unintended side-effects of unrelated hardware and software factors. B.Mouse-Operation T ask Design To reduce behavioral variations due to different mouse-operation sequences, all subjects were required to perform the same sequence of mouse operations. We knowing a mouse-operation task, consisting of a ? xed sequence of mouse operations, and made these operations exemplification of a typical and versatile combination of mouse operations. The operations were selected check to (1) two elementary operations of mouse dawns single click and doubling click and (2) two basic properties of mouse movements movement direction and movement distance 2, 39.As shown in Fig. 2, movement directions are numbered from 1 to 8, and each of them is selected to represent one of eight 45-degree look-alikes over 360 degrees. In addition, three distance musical intervals are considered to represent short-, lay- and long-distance mouse movements. table I shows the directions and distances of the mouse movements apply in this study. During data collection, every two adjacent movements were separated by either a single click or a double click. As a whole, the designed task consists of 16 mouse movements, 8 single clicks, and 8 double clicks.It should be noted that our task may not be unique. However, the task was carefully chosen to induce users to perform a wide variety of mouse movements and clicks that were both typical and diverse in an individuals repertoire of daily mouse behaviors. 1The mouse-behavior dataset is available from http//nskeylab. xjtu. edu. cn/ projects/mo utiliseynamics/behavior-data-set/. Fig. 2. Mouse movement directions sector 1 covers all operations performed degrees and degrees. with angles in the midst of give in I MOUSE MOVEMENTS IN THE DESIGNED MOUSE-OPERATION TASK C.Subjects We recruited 37 subjects, numerous from within our lab, but some from the university at large. Our type of subjects consisted of 30 males and 7 females. All of them were right-handed users, and had been using a mouse for a nominal of two years. D. Data-Collec tion Process All subjects were required to participate in two rounds of data collection per day, and waited at least 24 hours amidst collections (ensuring that some day-to-day variation existed within the data). In each round, each subject was invited, one by one, to perform the same mouse-operation task 10 times.A mouse-operation specimen was obtained when a subject performed the task one time, in which she ? rst clicked a start button on the screen, then moved the mouse to click subsequent buttons prompted by the data-collection application. Additionally, subjects were instructed to use only the external mouse device, and they were aware that no keyboard would be call for. Subjects were told that if they unavoidable a break or call for to stretch their hands, they were to do so after they had accomplished a full round. This was intended to prevent arti? cially anomalous mouse operations in the middle of a task.Subjects were admonished to focus on the task, as if they were lo gging into their own accounts, and to reverse distractions, such as talking with the experimenter, while the task was in progress. Any error in the operating process (e. g. , single-clicking a button when requiring double-clicking it) caused the current task to be reset, requiring the subject to redo it. 20 IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 fudge II MOUSE DYNAMICS FEATURES Subjects took amidst 15 days and 60 days to complete data collection.Each subject accomplished 150 error-free repetitions of the same mouse-operation task. The task took between 6. 2 seconds and 21. 3 seconds, with an medium of 11. 8 seconds over all subjects. The ? nal dataset contained 5550 hears from 37 subjects. IV. FEATURE construction In this section, we ? rst extract a set of mouse-dynamics features, and then we use distance-measurement methods to obtain feature-distance transmitters for reducing behavioral variability. Next, we utilize an eigenspace transformation to extract principal feature components as classi? er infix. A.Feature Extraction The data collected in Section III are sequences of mouse operations, including left-single-clicks, left-double-clicks, and mouse-movements. Mouse features were extracted from these operations, and were typically organized into a transmitter to represent the sequence of mouse operations in one execution of the mouse-operation task. display panel II summarizes the derived features in this study. We characterized mouse behavior based on two basic types of mouse operationsmouse click and mouse movement. Each mouse operation was then analyzed one by one, and translated into several mouse features.Our study divided these features into two categories Holistic features features that characterize the overall properties of mouse behaviors during interactions, such as single-click and double-click statistics Procedural features features that depict the lucubrate dynamic processes of mouse be haviors, such as the movement speed and acceleration curves. Most traditional features are holistic features, which suf? ce to obtain a statistical description of mouse behavior, such as the mean value of click times. They are easy to compute and comprehend, but they only characterize world(a) attributes of mouse behavior.In our study, the procedural features characterize in-depth procedural details of mouse behavior. This information more accurately re? ects the ef? ciency, agility and motion habits of individual mouse users, and thus may lead to a performance boost for authentication. data-based results in Section VII demonstrate the effectiveness of these newly-de? ned features. B. Distance metre The raw mouse features cannot be used directly by a classi? er, because of high dimensionality and behavioral variability. Therefore, distance-measurement methods were applied to obtain feature-distance transmitters and to mitigate the effects of these issues.In the weighing of distan ce measurement, we ? rst used the Dynamic Time Warping (DTW) distance 6 to compute the distance sender of procedural features. The reasons for this picking are that (1) procedural features (e. g. , movement speed curve) of two data try outs are not likely to consist of the exactly same number of points, whether these samples are generated by the same or by different subjects (2) DTW distance can be applied directly to measure the distance between the procedural features of two samples without deforming either or both of the two sequences in order to get an equal number of points.Next, we applied Manhattan distance to enter the distance sender of holistic features. The reasons for this picking are that (1) this distance is independent between dimensions, and can preserve physical interpretation of the features since its computation is the absolute value of cumulative difference (2) previous research in related ? elds (e. g. , keystroke dynamics) reported that the use of Manhatt an distance for statistical features could lead to a better performance 23. ) Reference Feature transmitter Generation We established the confabence feature vector for each subject from her learning feature vectors. Let , be the training set of feature vectors for one subject, where is a -dimensional mouse feature vector extracted from the th training sample, and is the number of training samples. Consider how the reference feature vector is generated for each subject measuring rod 1 we computed the pairwise distance vector of procedural features and holistic features between all pairs of training feature vectors and .We used DTW distance to calculate the distance vector of procedural features for measuring the similarity between the procedural components of the two feature vectors, and we applied Manhattan distance to calculate the distance vector of holistic features . (1) where , and represents the procedural components of represents the holistic components. SHEN et al. USER AUTHENTICATION THROUGH MOUSE DYNAMICS 21 Step 2 we concatenated the distance vectors of holistic features and procedural features together to obtain a distance vector for the training feature vectors and by (2) Step 3 we normalized vector to get a scale-invariant feature nd sample covariance . Then we can obtain the mean of such a training set by (5) (6) (3) is the mean of all where pairwise distance vectors from the training set, and is the corresponding standard deviation. Step 4 for each training feature vector, we calculate the arithmetic mean distance between this vector and the remaining training vectors, and found the reference feature vector with minimum mean distance. (4) 2) Feature-Distance Vector Calculation Given the reference feature vector for each subject, we then computed the feature-distance vector between a new mouse feature vector and the reference vector.Let be the reference feature vector for one subject then for any new feature vector (either from the legitima te user or an impostor), we can compute the corresponding distance vector by (1), (2) and (3). In this paper, we used all mouse features in Table II to generate the feature-distance vector. There are 10 click-related features, 16 distance-related features, 16 time-related features, 16 speed-related features, and 16 acceleration-related features, which were taken together and then transform to a 74-dimensional feature-distance vector that represents each mouse-operation sample. C.Eigenspace Computation Training and Projection It is usually undesirable to use all components in the feature vector as input for the classi? er, because much of data will not provide a signi? sham degree of uniqueness or consistency. We therefore applied an eigenspace-transformation technique to extract the principal components as classi? er input. 1) heart PCA Training Kernel principal component analysis (KPCA) 37 is one approach to generalizing linear PCA to nonlinear campaigns using kernel methods. In this study, the purpose of KPCA is to obtain the principal components of the lord feature-distance vectors.The unhurriedness process is illustrated as follows For each subject, the training set represents a set of feature-distance vectors drawn from her own data. Let be the th feature-distance vector in the training set, and be the number of such vectors. We ? rst mapped the measured vectors into the hyperdimensional feature space by the nonlinear mapping Here we centered the mapped point with the corresponding mean as . The principal components were then computed by firmness of purpose the eigenvalue problem (7) where and . Then, by de? ning a kernel matrix (8) we computed an eigenvalue problem for the coef? ients is now solely dependent on the kernel function , that (9) For details, readers can refer to B. Scholkopf et al. 37. Generally speaking, the ? rst few eigenvectors correspond to large eigenvalues and most information in the training samples. Therefore, for the sake of providing the principal components to represent mouse behavior in a low-dimensional eigenspace, and for memory ef? ciency, we ignored small eigenvalues and their corresponding eigenvectors, using a door value (10) is the accumulated variance of the ? st largest eigenwhere values with respect to all eigenvalues. In this study, was chosen as 0. 95 for all subjects, with a range from 0 to 1. Note that we used the same for different subjects, so may be different from one subject to another. Speci? cally, in our experiments, we noted that the number of principal components for different subjects varied from 12 to 20, and for an middling level, 17 principal components are identi? ed beneath the threshold of 0. 95. 2) Kernel PCA Projection For the selected subject, victorious the largest eigenvalues and he associated eigenvectors, the transform matrix can be constructed to project an original feature-distance vector into a point in the -dimensional eigenspace (11) As a result, each su bjects mouse behavior can be mapped into a manifold trajectory in such a parametric eigenspace. It is wellknown that is usually much smaller than the dimensionality of the original feature space. That is to say, eigenspace analysis can dramatically reduce the dimensionality of input samples. In this way, we used the extracted principal components of the feature-distance vectors as input for subsequent classi? ers. 22IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 V. CLASSIFIER IMPLEMENTATION This section explains the classi? er that we used, and introduces two other widely-used classi? ers. Each classi? er analyzes mouse-behavior data, and discriminates between a legitimate user and impostors. A. One-Class Classi? er Overview User authentication is still a contest task from the pattern-classi? cation perspective. It is a two-class (legitimate user versus impostors) problem. In the scenario of mouse-dynamicsbased user authentication, a login user is required to provide the user name and to perform a speci? mouse-operation task which would be secret, like a password. Each user would choose her own mouse-operations task, and would not share that task with others. Thus, when building a model for a legitimate user, the only behavioral samples of her speci? c task are her own other users (considered as impostors in our scenario) samples of this task are not readily available. In this scenario, therefore, an suppress solution is to build a model based only on the legitimate users data samples, and use that model to detect impostors. This type of problem is known as one-class classi? ation 43 or novelty/anomalousness detection 25, 26. We thus focused our attention on this type of problem, especially because in a real-world situation we would not have impostor renditions of a legitimate users mouse operations anyway. B. Our Classi? erOne-Class Support Vector appliance traditional one-class classi? cation methods are often unsatis fying, a great deal missing some true positives and producing too many false positives. In this study, we used a one-class Support Vector Machine (SVM) classi? er, introduced by Scholkopf et al. 36, 38. One-class SVMs have been successfully applied to a number of real-life classi? ation problems, e. g. , face authentication, signature veri? cation and keystroke authentication 1, 23. In our context, given training samples belonging to one subject, , each sample has features (corresponding to the principal components of the feature-distance vector for that subject). The aim is to ? nd a hyperplane that sepa judge the data points by the largest margin. To separate the data points from the origin, one needs to puzzle out the following dual quadratic programming problem 36, 38 the origin, and is the kernel function. We accommodate for nonlinear finish boundaries. Then the decision function 13) will be positive for the examples from the training set, where is the offset of the decisio n function. In essence, we viewed the user authentication problem as a one-class classi? cation problem. In the training phase, the learning task was to build a classi? er based on the legitimate subjects feature samples. In the testing phase, the test feature sample was projected into the same high-dimensional space, and the output of the decision function was recorded. We used a radial basis function (RBF) in our evaluation, after comparative studies of linear, polynomial, and sigmoidal kernels based on classi? ation accuracy. The SVM parameter and kernel parameter (using LibSVM 11) were set to 0. 06 and 0. 004 respectively. The decision function would generate if the authorized users test set is input otherwise it is a false rejection case. On the contrary, should be obtained if the impostors test set is the input otherwise a false acceptance case occurs. C. Other Classi? ersNearest Neighbor and Neural Network In addition, we compared our classi? er with two other widely-used classi? ers, KNN and neural lucre 12. For KNN, in the training phase, the nigh neighbor classi? r estimated the covariance matrix of the training feature samples, and saved each feature sample. In the testing phase, the hot neighbor classi? er cipher Mahalanobis distance from the new feature sample to each of the samples in the training data. The average distance, from the new sample to the nearest feature samples from the training data, was used as the anomalousness score. After duplex tests with ranging from 1 to 5, we obtained the best results with , enlarge in Section VII. For the neural web, in the training phase a network was built with input nodes, one output node, and hidden nodes.The network weights were randomly initialized between 0 and 1. The classi? er was trained to produce a 1. 0 on the output node for every training feature sample. We trained for 1000 epochs using a learning rate of 0. 001. In the testing phase, the test sample was run through the network, an d the output of the network was recorded. Denote to be the output of the network intuitively, if is close to 1. 0, the test sample is similar to the training samples, and with close to 0. 0, it is dissimilar. VI. EVALUATION METHODOLOGY This section explains the evaluation methodology for mouse behavior analysis.First, we summarize the dataset collected in Section III. Next, we set up the training and testing procedure for our one-class classi? ers. Then, we show how classi? er performance was calculated. Finally, we introduce a statistical testing method to further analyze experimental results. (12) where is the vector of nonnegative Lagrangian multipliers to be heady, is a parameter that controls the trade-off between maximizing the number of data points contained by the hyperplane and the distance of the hyperplane from SHEN et al. USER AUTHENTICATION THROUGH MOUSE DYNAMICS 23A. Dataset As discussed in Section III, samples of mouse-behavior data were collected when subjects perf ormed the designed mouseoperation task in a tightly-controlled environment. All 37 subjects produced a total of 5550 mouse-operation samples. We then calculated feature-distance vectors, and extracted principal components from each vector as input for the classi? ers. B. Training and Testing performance Consider a scenario as mentioned in Section V-A. We started by designating one of our 37 subjects as the legitimate user, and the rest as impostors. We trained the classi? er and ested its ability to recognize the legitimate user and impostors as follows Step 1 We trained the classi? er to build a pro? le of the legitimate user on a randomly-selected half of the samples (75 out of 150 samples) from that user. Step 2 We tried and true the ability of the classi? er to recognize the legitimate user by calculating anomaly stacks for the remaining samples generated by the user. We designated the wads assigned to each sample as genuine rack up. Step 3 We tested the ability of the clas si? er to recognize impostors by calculating anomaly scores for all the samples generated by the impostors.We designated the scores assigned to each sample as impostor scores. This process was then repeated, designating each of the other subjects as the legitimate user in turn. In the training phase, 10-fold cross check 24 was employed to choose parameters of the classi? ers. Since we used a random sampling method to divide the data into training and testing sets, and we wanted to account for the effect of this randomness, we repeated the above procedure 50 times, each time with independently selected samples drawn from the entire dataset. C. Calculating Classi? r Performance To convert these sets of classi? cation scores of the legitimate user and impostors into aggregate measures of classi? er performance, we computed the false-acceptance rate (FAR) and false-rejection rate (FRR), and used them to generate an ROC curve 42. In our evaluation, for each user, the FAR is calculated as the ratio between the number of false acceptances and the number of test samples of impostors the FRR is calculated as the ratio between the number of false rejections and the number of test samples of legitimate users.Then we computed the average FAR and FRR over all subjects. Whether or not a mouse-operation sample generates an alarm depends on the threshold for the anomaly scores. An anomaly score over the threshold indicates an impostor, while a score on a lower floor the threshold indicates a legitimate user. In many cases, to make a user authentication scheme deployable in practice, minimizing the possibility of rejecting a true user ( glare FRR) is sometimes more important than lowering the probability of evaluate an impostor 46. Thus we adjusted the threshold according to the FRR for the training data.Since calculation of the FRR requires only the legitimate users data, no impostor data was used for determining the threshold. Speci? cally, the threshold is set to be a v ariable ranging from , and will be chosen with a relatively low FRR using 10-fold cross validation on the training data. After multiple tests, we observe that setting the threshold to a value of 0. 1 yields a low FRR on average2. Thus, we show results with a threshold value of 0. 1 throughout this study. D. Statistical Analysis of the Results To evaluate the performance of our approach, we developed a statistical test using the half total error rate (HTER) and con? ence-interval (CI) evaluation 5. The HTER test aims to statistically evaluate the performance for user authentication, which is de? ned by combining false-acceptance rate (FAR) and falserejection rate (FRR) (14) Con? dence intervals are computed around the HTER as , and and are computed by 5 (15) % % % (16) where NG is the total number of genuine scores, and NI is the total number of impostor scores. VII. EXPERIMENTAL RESULTS AND ANALYSIS Extensive experiments were carried out to verify the effectiveness of our approach. First, we performed the authentication task using our approach, and compared it with two widely-used classi? rs. Second, we examined our primary results concerning the effect of eigenspace transformation methods on classi? er performance. Third, we explored the effect of sample distance on classi? er performance, to investigate the trade-off between security and usability. Two additional experiments are provided to compare our method with other approaches in the literature. A. investigate 1 User Authentication In this section, we conducted a user authentication experiment, and compared our classi? er with two widely-used ones as mentioned in Section V-C. The data used in this experiment consisted of 5550 samples from 37 subjects.Fig. 3 and Table III show the ROC curves and average FARs and FRRs of the authentication experiment for each of three classi? ers, with standard deviations in parentheses. Table III also includes the average authentication time, which is the sum of the ave rage time needed to collect the data and the average time needed to make the authentication decision (note that since the latter of these two times is ceaselessly less than 0. 003 seconds in our classi? ers, we ignore it in this study). Our ? rst observation is that the best performance has a FAR of 8. 74% and a FRR of 7. 96%, obtained by our approach (one-class SVM).This result is promising and competitive, and the behavioral samples are captured over a much shorter period of time 2Note that for different classi? ers, there are different threshold intervals. For instance, the threshold interval for neural network detector is 0, 1, and for one. For uniform presentation, we mapped all of intervals class SVM, it is . to 24 IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 TABLE IV HTER PERFORMANCE AND CONFIDENCE INTERVAL AT CONFIDENCE LEVELS assorted Fig. 3. ROC curves for the three different classi? rs used in this study oneclass SVM, neural netwo rk, and nearest neighbor. TABLE III FARs AND FRRs OF USER AUTHENTICATION EXPERIMENT (WITH metre DEVIATIONS IN PARENTHESES) information about mouse behavior, which could enhance performance. Finally, we conducted a statistical test, using the HTER and CI evaluation as mentioned in Section VI-D, to statistically evaluate the performance of our approach. Table IV summarizes the results of this statistical evaluation at different con? dence levels. The result shows that the proposed approach provides the lowest HTER in comparison with the other two classi? ers used in our study the 95% con? ence interval lies at % %. B. experiment 2 incumbrance of Eigenspace Transformation This experiment examined the effect of eigenspace-transformation methods on classi? er performance. The data used were the same as in Experiment 1. We applied a one-class SVM classi? er in three evaluations, with the inputs respectively set to be the original feature-distance vectors (without any transformations), t he extrusion of feature-distance vectors by PCA, and the projection of feature-distance vectors by KPCA. Fig. 4 and Table V show the ROC curves and average FARs and FRRs for each of three feature spaces, with standard deviations in parentheses.As shown in Fig. 4 and Table V, the authentication accuracy for the feature space transformed by KPCA is the best, followed by the accuracies for feature spaces by PCA and the original one. Speci? cally, direct classi? cation in the original feature space (without transformations) produces a FAR of 15. 45% and FRR of 15. 98%. This result is not encouraging compared to results previously reported in the literature. However, as mentioned in Experiment 1, the samples may be subject to more behavioral variability compared with previous work, because previous work analyzed mouse behaviors over a protracted period of observation.Moreover, we observe that the authentication results of % % by PCA, and % % by KPCA are much better than for direct clas si? cation. This result is a demonstration of the effectiveness of the eigenspace transformation in dealing with variable behavior data. Furthermore, we ? nd that the performance of KPCA is more or less superior to that of PCA. This may be due to the nonlinear variability (or noise) existing in mouse behaviors, and KPCA can reduce this variability (or noise) by using kernel transformations 29.It is also of note that the standard deviations of FAR and FRR based on the feature space transformed by KPCA and PCA are smaller than those of the original feature space (without transformations), indicating that the eigenspace-transformation technique enhances the stability and robustness of our approach. compared with previous work. It should be noted that our result does not yet meet the European standard for commercial biometric technology, which requires near-perfect accuracy of 0. 001% FAR and 1% FRR 10. notwithstanding it does demonstrate that mouse dynamics could provide valuable inf ormation in user authentication tasks.Moreover, with a series of incremental returnss and investigations (e. g. , outlier handling), it seems possible that mouse dynamics could be used as, at least, an auxiliary authentication technique, such as an sweetening for conventional password mechanisms. Our second observation is that our approach has substantially better performance than all other classi? ers considered in our study. This may be due to the fact that SVMs can convert the problem of classi? cation into quadratic optimization in the case of relative insuf? ciency of prior knowledge, and still maintain high accuracy and stability.In addition, the standard deviations of the FAR and FRR for our approach are much smaller than those for other classi? ers, indicating that our approach may be more robust to variable behavior data and different parameter selection procedures. Our third observation is that the average authentication time in our study is 11. 8 seconds, which is impre ssive and achieves an acceptable level of performance for a practical application. Some previous approaches may lead to low availability due to a relatively-long authentication time. However, an authentication time of 11. seconds in our study shows that we can perform mouse-dynamics analysis quickly enough to make it applicable to authentication for most login processes. We conjecture that the signi? cant decrease of authentication time is due to procedural features providing more detailed and ? ne-grained SHEN et al. USER AUTHENTICATION THROUGH MOUSE DYNAMICS 25 TABLE VI FARs AND FRRs OF DIFFERENT SAMPLE LENGTHS Fig. 4. ROC curves for three different feature spaces the original feature space, the projected feature space by PCA, and the projected feature space by KPCA.TABLE V FARs AND FARs FOR THREE DIFFERENT FEATURE SPACES (WITH STANDARD DEVIATIONS IN PARENTHESES) the needs of the European Standard for commercial biometric technology 10. We ? nd that after observing 800 mouse ope rations, our approach can obtain a FAR of 0. 87% and a FRR of 0. 69%, which is very close to the European standard, but with a corresponding authentication time of about 10 proceeding. This long authentication time may limit applicability in real systems. Thus, a trade-off must be made between security and user acceptability, and more nvestigations and improvements should be performed to secure a place for mouse dynamics in more pragmatic settings. D. comparison User authentication through mouse dynamics has attracted growing interest in the research community. However, there is no shared dataset or baseline algorithm for measuring and determining what factors affect performance. The unavailability of an accredited common dataset (such as the FERET database in face recognition 32) and standard evaluation methodology has been a limitation in the development of mouse dynamics.Most researchers trained their models on different feature sets and datasets, but none of them made informed comparisons among different mouse feature sets and different results. Thus two additional experiments are offered here to compare our approach with those in the literature. 1) Comparison 1 Comparison With Traditional Features As stated above, we constructed the feature space based on mouse clicks and mouse movements, consisting of holistic features and procedural features. To further examine the effectiveness of the features constructed in this study, we provide a comparative experiment. We chose the features used by Gamboa et al. 17, Aksari and Artuner 4, Hashia et al. 19, Bours and Fullu 8, and Ahmed and Traore 2, because they were among the most frequently cited, and they represented a relatively diverse set of mouse-dynamics features. We then used a one-class SVM classi? er to conduct the authentication experiment again on our same dataset with both the feature set de? ned in our study, and the feature sets used in other studies. Hence, the authentication accuracies of different feature sets can be compared. Fig. 5 and Table VII show the ROC curves and average FARs and FRRs for each of half a dozen feature sets, with standard deviations in parentheses.We can see that the average error rates for the feature set from our approach are much lower than those of the feature sets from the literature. We conjecture that this may be due to the procedural features providing ? ne-grained information about mouse behavior, but they may also be due, in part, to (1) partial adoption of features de? ned in previous approaches C. Experiment 3 Effect of Sample Length This experiment explored the effect of sample duration on classi? er performance, to investigate the trade-off between security (authentication accuracy) and usability (authentication time).In this study, the sample length corresponds to the number of mouse operations needed to form one data sample. Each original sample consists of 32 mouse operations. To explore the effect of sample length on the performance of our approach, we derived new datasets with different sample lengths by applying aid sampling techniques 13 to the original dataset, to make derived datasets containing the same add up of samples as the original dataset. The new data samples were generated in the form of multiple consecutive mouse samples from the original dataset. In this way, we considered classi? r performance as a function of the sample length using all bootstrap samples derived from the original dataset. We conducted the authentication experiment again (using one-class SVM) on six derived datasets, with and 800 operations. Table VI shows the FARs and FRRs at varying sample lengths, using a one-class SVM classi? er. The table also includes the authentication time in seconds. The FAR and FRR obtained using a sample length of 32 mouse operations are 8. 74% and 7. 96% respectively, with an authentication time of 11. 8 seconds. As the number of operations increases, the FAR and FRR drop to 6. 7% and 6. 68% for t he a data sample comprised of 80 mouse operations, corresponding to an authentication time of 29. 88 seconds. Therefore, we may conclude that classi? er performance almost certainly gets better as the sample length increases. Note that 60 seconds may be an swiftness bound for authentication time, but the corresponding FAR of 4. 69% and FRR of 4. 46% are still not low enough to meet 26 IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 8, NO. 1, JANUARY 2013 Fig. 5. ROC curves for six different feature sets the feature set in our study, and the features sets in other studies.RESULTS OF TABLE VII COMPARISON WITH SOME TRADITIONAL FEATURES (WITH STANDARD DEVIATIONS IN PARENTHESES) Note that this approach 2 is initially applied to intrusion detection, and we extracted parts of features closely related to mouse operations in our dataset. The reason for this decision is that we want to examine whether the features employed in intrusion detection can be used in user authenticati on. because of different data-collection environments (2) using different types of thresholds on the anomaly scores (3) using less enrollment data than was used in previous experiments.The better performance based on using our features also indicates that our features may allow more accurate and detailed characterization of a users unique mouse behavior than was possible with previously used features. Another thing to note from Table VII is that the standard deviations of error rates for features in our study are smaller than those for traditional features, suggesting that our features skill be more stable and robust to variability in behavior data. One may also wonder how much of the authentication accuracy of our approach is due to the use of procedural features or holistic features.We tested our method using procedural features and holistic features separately, and the set of procedural features was the choice that proved to perform better. Specifically, we observe that the auth entication accuracy of % % by using the set of procedural features is much better than for the set of holistic features, which have a FAR of 19. 58% and a FRR of 17. 96%. In combination with the result when using all features, it appears that procedural features may be more stable and discriminative than holistic features, which suggests that the procedural features contribute more to the authentication accuracy.The results here only provide preliminary comparative results and should not be used to conclude that a certain set of mouse features is eternally better than others. Each feature set has its own unique advantages and disadvantages under different conditions and applications, so further evaluations and comparisons on more existent and challenging datasets are needed. 2) Comparison 2 Comparison With Previous Work Most previous approaches have either resulted in poor performance (in foothold of authentication accuracy or time), or have used data of limited size.In this sect ion, we show a qualitative comparison of our experimental results and settings against results of previous work (listed in Table VIII). Revett et al. 34 and Aksari and Artuner 4 considered mouse dynamics as a standalone biometric, and obtained an authentication accuracy of ERR around 4% and 5. 9% respectively, with a relatively-short authentication time or small number of mouse operations. But their results were based on a small pool of users (6 users in 34 and 10 users in 4), which may be insuf? ient to obtain a good, steady result. Our study relies on an improved user authentication methodology and far more users, leading us to achieve a good and robust authentication performance. Ahmed and Traore 2 achieved a high authentication accuracy, but as we mentioned before, it might be dif? cult to use such a method for user authentication since the authentication time or the number of mouse operations needed to verify a users identity is too high to be practical for real systems. Additi onally, Hashia et al. 19 and Bours and Fulla 8 could perform user authentication in a relatively-short time, but they reported unacceptably high error rates (EER of 15% in 19, and EER of 26. 8% in 8). In our approach we can make an authentication decision with a reasonably short authentication time while maintaining high accuracy. We employ a one-class classi? er, which is more appropriate for mouse-dynamics-based user authentication. As mentioned in Experiment 3, we can make an authentication decision in less than 60 seconds, with corresponding error rates are FAR of 4. 9% and FRR of 4. 46%. Although this result could be improved, we gestate that, at our current performance level, mouse dynamics suf? ce to be a practical auxiliary authentication mechanism. In summary, Comparison 1 shows that our proposed features outperform some traditional features used in previous studies, and may be more stable and robust to variable behavior data. Comparison 2 indicates that our approach is co mpetitive with existing approaches in authentication time while maintaining high accuracy.More detailed statistical studies on larger and more realistic datasets are desirable for further evaluations. VIII. DISCUSSION AND EXTENSION FOR future WORK Based on the ? ndings from this study, we take away some messages, each of which may suggest a trajectory for future work. Additionally, our work highlights the need for shared data and resources. A. Success Factors of Our Approach The presented approach achieved a short authentication time and relatively-high accuracy for mouse-dynamics-based user SHEN et al. USER AUTHENTICATION THROUGH MOUSE DYNAMICS 27 TABLE VIII COMPARISON WITH preceding(prenominal) WORKAuthentication time was not explicitly reported in 4, 8, 17 instead, they required the user to accomplish a number of mouse operations for each authentication (15 clicks and 15 movements for 17 10 clicks and 9 movements for 4 18 short movements without pauses for 8). Authentication t ime was not explicitly stated in 2 however, it can be sham by data-collection progress. For example, it is stated in 2 that an average of 12 hours 55 minutes of data were captured from each subject, representing an average of 45 sessions. We therefore assume that average session length is 12. 5 60/45 17. 22 minutes 1033 seconds. authentication. However, it is quite hard to point out one or two things that may have made our results better than those of previous work, because (1) past work favored realism over experimental control, (2) evaluation methodologies were inconsistent among previous work, and (3) there have been no public datasets on which to perform comparative evaluations. Experimental control, however, is likely to be responsible for much of our success. Most previous work does not reveal any particulars in controlling experiments, while our work is tightly controlled.We made every effort to control experimental confounding factors to prevent them from having unintended in? uence on the subjects recorded mouse behavior. For example, the same desktop computer was used for data collection for all subjects, and all system parameters relating to the mouse were ? xed. In addition, every subject was provided with the same instructions. These settings suggest strongly that the differences in subjects were due to individually perceptible mouse-behavior differences among subjects, and not to environmental variables or experimental conditions.We strongly barrack the control of potential confounding factors in future experiments. The reason is that controlled experiments are necessary to reveal causal connections among experimental factors and classi? er performance, while realistic but uncontrolled experiments may introduce confounding factors that could in? uence experimental outcomes, which would make it hard to tell whether the results of those evaluations actually re? ect detectable differences in mouse behavior among test subjects, or differences among computing environments.We had more subjects (37), more repetitions of the operation task (150), and more comprehensive mouse operations (2 types of mouse clicks, 8 movement directions, and 3 movement distance ranges) than most studies did. Larger subject pools, however, sometimes make things harder when there are more subjects there is a higher possibility that two subjects will have similar mouse behaviors, resulting in more classi? cation errors. We proposed the use of procedural features, such as the movement speed curve and acceleration curve, to provide more ? egrained information about mouse behavior than some traditional features. This may allow one to accurately describe a users unique mouse behavior, thus leading to a performance improvement for mouse-dynamics-based user authentication. We adopted methods for distance measurement and eigenspace transformation for obtaining principal feature components to ef? ciently represent the original mouse feature space. These methods not only worst within-class variability of mouse behavior, but also preserve between-class differences of mouse behavior. The improved authentication accuracies demonstrate the ef? acy of these methods. Finally, we used a one-class learning algorithm to perform the authentication task, which is more appropriate for mousedynamics-based user authentication in real applications. In general, until there is a comparative study that stabilizes these factors, it will be hard to be de? nitive about the precise elements that made this work successful. B. Opportunities for expediency While previous studies showed promising results in mouse dynamics, none of them have been able to meet the requirement of the European standard for commercial biometric technology.In this work, we determined that mouse dynamics may achieve a pragmatically reclaimable level of accuracy, but with an impractically long authentic