Poisson factorization for peer-based anomaly detection

Anomaly detection systems are a promising tool to identify compromised user credentials and malicious insiders in enterprise networks. Most existing approaches for modelling user behaviour rely on either independent observations for each user or on pre-defined user peer groups. A method is proposed based on recommender system algorithms to learn overlapping user peer groups and to use this learned structure to detect anomalous activity. Results analysing the authentication and process-running activities of thousands of users show that the proposed method can detect compromised user accounts during a red team exercise

Correlations and invariance of seismicity under renormalization-group transformations

The effect of transformations analogous to those of the real-space renormalization group are analyzed for the temporal occurrence of earthquakes. The distribution of recurrence times turns out to be invariant under such transformations, for which the role of the correlations between the magnitudes and the recurrence times are fundamental. A general form for the distribution is derived imposing only the self-similarity of the process, which also yields a scaling relation between the Gutenberg-Richter b-value, the exponent characterizing the correlations, and the recurrence-time exponent. This approach puts the study of the structure of seismicity in the context of critical phenomena.Comment: Short paper. I'll be grateful to get some feedbac

Helping the Adult Learner Succeed: How Community College Libraries in Massachusetts are Serving this Growing Population

Education is something that is valued more each and every day. A growing number of people in today’s society realize the importance of education and the increasing need to return to school. As the number of adult learners continues to rise, so too does the need to reach out to this population to make sure they are being presented with the appropriate tools and resources needed to succeed. Because it is theorized that adults (those age 25+) who return to school are likely to enroll in a community college, rather than a four year university, this study looks specifically at community colleges in Massachusetts in an effort to judge what is being done to help this often overlooked population, as well as what could be improved. To make this determination, a brief survey was sent to 25 reference librarians at 13 different Massachusetts community colleges. They results of the survey were then analyzed, along with previously written literature on this topic. The survey confirmed earlier findings that adult learners commonly struggle with issues of a technological nature. These issues include troubles using computers and the internet, as well as using word processing software, and databases. To help adult learners succeed, collaboration is a key component. This collaboration should extend to the information technology department, department heads, librarians, instructors, information literacy coordinators, and most importantly, the student. Communication between all of these groups is needed to ensure the success of adult learners. This paper will explore these barriers, as well as other obstacles adult learners face, and also provide further recommendations as to what can be done to help this growing population of students

When You Should Have Known: Rethinking Constructive Knowledge in Tort Liability for Sexual Transmission of HIV

AIDS is a modern epidemic that has grabbed the forefront of this nation\u27s attention like no other disease in the twentieth century. Despite vigorous medical research and experimentation, the disease remains incurable and ultimately fatal. Protecting the health of the citizens has always been a strong policy of the law. Tort liability for the spread of contagious diseases dates back to the early nineteenth century. Tort liability for sexual transmission of AIDS began to appear in the late 1980s, not long after the appearance of the disease. Based as it was on the tort actions arising from other transmittable diseases, tort liability invariably required a showing that the defendant knew that he or she was infected with the disease before the sexual contact took place. AIDS is unlike other sexually transmitted diseases. It is stealthy, with a lengthy and symptom-free incubation period which may last for a decade or more. During this time, the infected individual could infect any number of persons, limited only by the number of sexual partners the infected party is able to contact. Although having sex with an HIV-infected individual does not guarantee that one will contract the virus, it is certainly a foreseeable consequence of such conduct. Under the current standards of tort liability, HIV-infected individuals will almost always plead a lack of knowledge defense. Unless the standards of when it is reasonable for a person to have constructive knowledge of his or her HIV infection are extended to persons who, for a variety of reasons, should have known that they were HIV-positive or at great risk to be HIV-positive, a plaintiff may not be able to successfully bring an action in tort. Tort law is intended to apportion responsibility to those who have committed a wrong. It goes against the great weight of tort law to allow HIV-infected individuals to escape tort liability due to the particular nature of this contagious disease. Persons who are infected with HIV or who, because of particular information known to them know that they are at high-risk for being infected with HIV, owe a duty to all future sexual partners to either disclose their serostatus, or to warn of the possible risk. Failing that, these individuals have a duty to abstain from sexual contact with unsuspecting partners until the partners have been informed. After disclosure, if a partner chooses to engage in sexual contact with the infected or at-risk individual, then that person has made an informed choice. If that party attempts a tort action later, arising from HIV-infection, then the defendant may raise a comparative or contributory negligence defense, or assumption of risk defense, depending on the jurisdiction. The risk of HIV infection and the consequences of the spread of this disease are just now becoming apparent eighteen years after the appearance of the disease. In the United States alone, the Center for Disease Control reported that 390,692 persons had died of AIDS as of December 1997. Another 665,397 Americans were living with AIDS as of June 30, 1998. Outside of the United States, the statistics are far worse. By extending tort liability to persons who should know that they are HIV-positive or to those who know that they are at high-risk for HIV infection, two purposes can be met. First, individuals who contract HIV through sexual contact may have legal remedies against the partners who infected them. The liability in these cases will be restricted to persons who had a duty to warn the plaintiff of the risk of HIV infection, but failed to do so. This liability will serve as an incentive to disclose one\u27s conditions and risk factors to one\u27s future sexual partners, thus probably limiting the spread of the disease. Second, extending tort liability will encourage HIV testing; more testing will foster improved treatment of HIV and further limit its spread through sexual transmission. This Comment focuses on the causes of action arising from the sexual transmission of AIDS

A renormalization group model for the stick-slip behavior of faults

A fault which is treated as an array of asperities with a prescribed statistical distribution of strengths is described. For a linear array the stress is transferred to a single adjacent asperity and for a two dimensional array to three ajacent asperities. It is shown that the solutions bifurcate at a critical applied stress. At stresses less than the critical stress virtually no asperities fail on a large scale and the fault is locked. At the critical stress the solution bifurcates and asperity failure cascades away from the nucleus of failure. It is found that the stick slip behavior of most faults can be attributed to the distribution of asperities on the fault. The observation of stick slip behavior on faults rather than stable sliding, why the observed level of seismicity on a locked fault is very small, and why the stress on a fault is less than that predicted by a standard value of the coefficient of friction are outlined

Un mode de pondération de données provenant d’enquêtes longitudinales

Lors de l’étape du traitement de données provenant d’enquêtes longitudinales, le méthodologue désire vérifier si les distributions des estimations correspondent, soit dans le temps, soit à divers stades de la période d’enquête, à certaines distributions externes. A ce titre, les auteurs se réfèrent à des travaux méthodologiques et informatiques récents pour concevoir une nouvelle façon d’ajuster les estimations selon une séquence et un nombre d’itérations prescrits. Cette exploitation conjuguée de la technique de l’estimation par le quotient et du programme informatique THAID apporte, à toute fin, une possibilité inédite de valider le procédé de pondération

Reader’s Advisory in the Academic Library: Should You? (Yes!) Could You? (Yes!)

This poster highlights the research surrounding the academic and social benefits of leisure reading among college students. A case scenario of the inclusion of a popular titles collection at an academic library is also included as an additional document