Accepted papers include:

A Modified Fuzzy C-Means Algorithm For Collaborative Filtering

Putting the collaborator back into collaborative filtering

Improved Neighborhood-Based Algorithms for Large-Scale Recommender Systems

Large-scale recommenders based on Association Rule Mining

From hits to niches? or how popular artists can bias music recommendations

Investigation of Various Matrix Factorization Methods for Large Recommender Systems

Second KDD Workshop on Large-Scale Recommender Systems and the Netflix Prize Competition

The National Aeronautics and Space Administration (NASA) estimates that without a servicing mission to replace key components, the Hubble Space Telescope will cease scientific operations in 2008. In January 2004, then-NASA Administrator Sean O'Keefe announced that the space shuttle would no longer be used to service Hubble. He indicated that this decision was based primarily on safety concerns in the wake of the space shuttle Columbia accident in 2003. Many critics, however, saw it as the result of the new Vision for Space Exploration, announced by President Bush in January 2004, which focuses NASA's priorities on human and robotic exploration of the solar system. Hubble supporters sought to reverse the decision and proceed with a shuttle servicing mission. Michael Griffin, who became NASA Administrator in April 2005, stated that he would reassess whether to use the shuttle to service Hubble after there were two successful post-Columbia shuttle flights. The second post-Columbia flight took place successfully in July 2006. In October 2006, NASA approved a shuttle mission to service Hubble. That mission is now scheduled for October 8, 2008.

Hubble Space Telescope: NASA's Plans for a Servicing Mission

The future of both law and technology will require reconciling users' desire to self-disclose information with their simultaneous desire that this information be protected. Security of personal information and user privacy are potentially irreconcilable with the conflicting set of user preferences regarding information sharing behaviours and the convenience of using technology to do so. Social networking sites (SNSs) provide the latest and perhaps most complicated case study to date of these technologies where consumers' desire for data security and control conflict with their desire to self-disclose. Although the law may provide some data control protections, aspects of the code itself provide equally important means of achieving a delicate balance between users' expectations of data security and privacy and their desire to share information.

Data Control and Social Networking: Irreconcilable Ideas?

Reputation systems constitute an important institution to help sustain trust in online auction markets. However, only half of buyers leave feedback after transactions, and nearly all of it is positive. In this paper, I propose a mechanism whereby sellers can provide rebates (not necessarily in monetary form) to buyers contingent upon buyers' provision of reports. Using a game theoretical model, I show how the mechanism can increase unbiased reporting. There exists a pooling equilibrium where both good and bad sellers choose the rebate option, even though their true types are revealed through feedback. The mechanism also induces bad sellers to improve the quality of the contract.

Reputation, Trust, and Rebates: How Online Auction Markets Can Improve Their Feedback Mechanisms

Recently, some scholars and government officials have called for the creation of “national security courts”—specialized hybrid tribunals that would review the preventive detention of suspected terrorists (both within and outside of the territorial United States), conduct the detainees’ criminal trials, or, in some cases, both.1 Advocates for these courts claim that they offer an attractive middle ground between adherence to traditional criminal processes and radical departures from those processes.2

For the reasons that follow, we, the undersigned members of the Constitution Project’s Liberty and Security Committee and its Coalition to Defend Checks and Balances, believe that the proposals to create these courts should be resisted. The proposals are surprisingly—indeed alarmingly—underdeveloped. More seriously, they neglect basic and fundamental principles of American constitutional law, and they assume incorrectly that the traditional processes have proven ineffective. The idea that there is a class of individuals for whom neither the normal civilian or military criminal justice systems suffice presupposes that such a class of individuals is readily identifiable—and in a manner that does not necessarily pre-judge their guilt. The idea that national security courts are a proper third way for dealing with such individuals presupposes that the purported defects in the current system are ones that cannot adequately be remedied within the confines of that system, and yet can be remedied in new tribunals without violating the Constitution.

We believe that the government can accomplish its legitimate goals using existing laws and legal procedures without resorting to such sweeping and radical departures from an American constitutional tradition that has served us effectively for over two centuries. We separately address below proposals for a national security court for criminal prosecutions of terrorism suspects and proposals for such a court to review preventive detention decisions, and the reasons why each should be rejected.

A Critique of "National Security Courts"

The subprime mortgage crisis has already wreaked havoc on the lives of millions of people and now it threatens to derail the U.S. economy and economies around the world. In this trenchant book, best-selling economist Robert Shiller reveals the origins of this crisis and puts forward bold measures to solve it. He calls for an aggressive response--a restructuring of the institutional foundations of the financial system that will not only allow people once again to buy and sell homes with confidence, but will create the conditions for greater prosperity in America and throughout the deeply interconnected world economy.

Shiller blames the subprime crisis on the irrational exuberance that drove the economy's two most recent bubbles--in stocks in the 1990s and in housing between 2000 and 2007. He shows how these bubbles led to the dangerous overextension of credit now resulting in foreclosures, bankruptcies, and write-offs, as well as a global credit crunch. To restore confidence in the markets, Shiller argues, bailouts are needed in the short run. But he insists that these bailouts must be targeted at low-income victims of subprime deals. In the longer term, the subprime solution will require leaders to revamp the financial framework by deploying an ambitious package of initiatives to inhibit the formation of bubbles and limit risks, including better financial information; simplified legal contracts and regulations; expanded markets for managing risks; home equity insurance policies; income-linked home loans; and new measures to protect consumers against hidden inflationary effects.

This powerful book is essential reading for anyone who wants to understand how we got into the subprime mess--and how we can get out.

The Subprime Solution: How Today's Global Financial Crisis Happened, and What to Do about It

Digital communication is profoundly affecting the constitution of (civil) society by drastically lowering the costs to speak across time and space with individuals and groups of any size, and by producing abundant records of all activities conducted through these media. This is accelerating two contradictory trends. On the one hand, a new breed of social organizations based on principles of weak cooperation and peer production is sharply expanding the scope of what can be achieved by civil society. These are voluntary organizations, with flat hierarchies and trust–based principles. They are focused on producing commons–based resources rather than individual property. In general, they are transformative, not revolutionary, in character. This phenomenon is termed “bourgeois anarchism.” On the other hand, the liberal state — in a crisis of legitimacy and under pressure from such new organizations, both peaceful (civil society) and violent (terrorism) — is reorganizing itself around an increasingly authoritarian core, expanding surveillance into the capillary system of society, overriding civil liberties and reducing democratic oversight in exchange for the promise of security. This phenomenon is termed “authoritarian democracies.”

Bourgeois anarchism and authoritarian democracies

Walter Benjamin’s famous “Work of Art” essay sets out his boldest thoughts—on media and on culture in general—in their most realized form, while retaining an edge that gets under the skin of everyone who reads it. In this essay the visual arts of the machine age morph into literature and theory and then back again to images, gestures, and thought.

This essay, however, is only the beginning of a vast collection of writings that the editors have assembled to demonstrate what was revolutionary about Benjamin’s explorations on media. Long before Marshall McLuhan, Benjamin saw that the way a bullet rips into its victim is exactly the way a movie or pop song lodges in the soul.

This book contains the second, and most daring, of the four versions of the “Work of Art” essay—the one that addresses the utopian developments of the modern media. The collection tracks Benjamin’s observations on the media as they are revealed in essays on the production and reception of art; on film, radio, and photography; and on the modern transformations of literature and painting. The volume contains some of Benjamin’s best-known work alongside fascinating, little-known essays—some appearing for the first time in English. In the context of his passionate engagement with questions of aesthetics, the scope of Benjamin’s media theory can be fully appreciated.

The Work of Art in the Age of Its Technological Reproducibility, and Other Writings on Media

Passwords are ubiquitous, and users and service providers alike rely on them for their security. However, good passwords may sometimes be hard to remember. For years, security practitioners have battled with the dilemma of how to authenticate people who have forgotten their passwords. Existing approaches suffer from high false positive and false negative rates, where the former is often due to low entropy or public availability of information, whereas the latter often is due to unclear or changing answers, or ambiguous or fault prone entry of the same. Good security questions should be based on long-lived personal preferences and knowledge, and avoid publicly available information. We show that many of the questions used by online matchmaking services are suitable as security questions. We first describe a new user interface approach suitable to such security questions that is offering a reduced risk of incorrect entry. We then detail the findings of experiments aimed at quantifying the security of our proposed method.

Love and Authentication

In spite of its tremendous value, metadata is generally sparse and incomplete, thereby hampering the effectiveness of digital information services. Many of the existing mechanisms for the automated creation of metadata rely primarily on content analysis which can be costly and inefficient. The automatic metadata generation system proposed in this article leverages resource relationships generated from existing metadata as a medium for propagation from metadata-rich to metadata-poor resources. Because of its independence from content analysis, it can be applied to a wide variety of resource media types and is shown to be computationally inexpensive. The proposed method operates through two distinct phases. Occurrence and co-occurrence algorithms first generate an associative network of repository resources leveraging existing repository metadata. Second, using the associative network as a substrate, metadata associated with metadata-rich resources is propagated to metadata-poor resources by means of a discrete-form spreading activation algorithm. This article discusses the general framework for building associative networks, an algorithm for disseminating metadata through such networks, and the results of an experiment and validation of the proposed method using a standard bibliographic dataset.

Automatic Metadata Generation using Associative Networks