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

In computer science, conferences are often the primary medium of scientific communication, and conference submissions are reviewed at least as stringently as journal papers. Despite the importance of the process, not much has been written on the subject.

Reviewing Conference Papers

Where would we be without rating and reputation systems these days? Take them away, and we wouldn’t know who to trust on eBay, what movies to pick on Netflix, or what books to buy on Amazon. Reputation systems (essentially a rating system for people) also help guide us through the labyrinth of individuals who make up our social web. Is he or she worthwhile to spend my time on? For pity’s sake, please don’t check out our reputation points before deciding whether to read this article.

Rating and reputation systems have become standard tools in our design toolbox. But sometimes they are not well-understood. A recent post at the IxDA forum showed confusion about how and when to use rating systems. Much of the conversation was about whether to use stars or some other iconography. These can be important questions, but they miss the central point of ratings systems: to manage risk.

So, when we think about rating and reputation systems, the first question to ask is not, “Am I using stars, bananas, or chili peppers?” but, “what risk is being managed?”

On A Scale of 1 to 5: Understanding Risk Improves Rating and Reputation Systems

Wordle is a toy for generating “word clouds” from text that you provide. The clouds give greater prominence to words that appear more frequently in the source text. You can tweak your clouds with different fonts, layouts, and color schemes. The images you create with Wordle are yours to use however you like. You can print them out, or save them to the Wordle gallery to share with your friends.

Wordle - Beautiful Word Clouds

This visualization, called code_swarm, shows the history of commits in a software project. A commit happens when a developer makes changes to the code or documents and transfers them into the central project repository. Both developers and files are represented as moving elements. When a developer commits a file, it lights up and flies towards that developer. Files are colored according to their purpose, such as whether they are source code or a document. If files or developers have not been active for a while, they will fade away. A histogram at the bottom keeps a reminder of what has come before.

code_swarm, an experiment in organic software visualization

This paper proposes a new method for displaying large-scale tag clouds. We use a topographical image that helps users to grasp the relationship among tags intuitively as a background to the tag clouds. We apply this interface to a blog navigation system and show that the proposed method enables users to find the desired tags easily even if the tag clouds are very large, 5,000 and above tags. Our approach is also effective for understanding the overall structure of a large amount of tagged documents.

You can still read the full paper without an ACM Digital Library subscription.

Topigraphy: visualization for large-scale tag clouds

This paper describes a distributed collaborative wiki-based platform that has been designed to facilitate the development of Semantic Web applications. The applications designed using this platform are able to build semantic data through the cooperation of different developers and to exploit that semantic data. The paper shows a practical case study on the application VPOET, and how an application based on Google Gadgets has been designed to test VPOET and let human users exploit the semantic data created. This practical example can be used to show how different Semantic Web technologies can be integrated into a particular Web application, and how the knowledge can be cooperatively improved.

VPOET: Using a Distributed Collaborative Platform for Semantic Web Applications

The visions of Buckminster Fuller.

Annals of Innovation: Dymaxion Man

Drainage tunnels beneath the Strip exert an unnatural pull on artists whose work rarely sees the light of day

Underground gallery - Las Vegas Sun - Graffiti