Alex Cozzi

Graph-based ranking algorithms for e-mail expertise analysis

In this paper we study graph--based ranking measures for the purpose of using them to rank email correspondents according to their degree of expertise on subjects of interest. While this complete expertise analysis consists of several steps, in this paper we focus on the analysis of digraphs whose nodes correspond to correspondents (people), whose edges correspond to the existence of email correspondence between the people corresponding to the nodes they connect and whose edge directions point from the member of the pair whose relative expertise has been estimated to be higher. We perform our analysis on both synthetic and real data and we introduce a new error measure for comparing ranked lists.

Hitting the distributed computing sweet spot with TSpaces

Abstract Our world is becoming increasingly heterogeneous, decentralized and distributed, but the software that is supposed to work in this world, usually, is not. TSpaces is a communication package whose purpose is to alleviate the problems of hooking together disparate distributed systems. TSpaces is a global communication middleware component that incorporates database features, such as transactions, persistent data, flexible queries and XML support. TSpaces is an excellent tool for building distributed applications, since it provides an asynchronous and anonymous link between multiple clients or services. The communication link provided by TSpaces gives application builders the advantage of ignoring some of the harder aspects of multi-client synchronization, such as tracking names (and addresses) of all active clients, communication line status, and conversation status. For many different types of applications, the loose synchronization provided by TSpaces works extremely well. This paper relates our experiences in building distributed systems with TSpaces as the central communication component.

Unified activity management: supporting people in e-business

Meshing formal business processes with informal human collaborations is needed to support business activities.

Roles and relationships for unified activity management

This paper reports on three ethnographic studies of how people coordinate their activities in various work settings. The findings reported here are a derived set of relationships reflecting the nature of involvement of people in their activities. These findings were then tested by six analysts, who were conducting field studies of patterns of complex business activities. They used the derived relationships in the analysis of their data and in the representation of activity patterns. These usage cases revealed confusion between involvement relationships and job roles. Finally, several implications of these studies for designing an activity management prototype are presented.

COMVIS: A Communication Framework for Computer Vision

We describe a general approach to integrate the information produced by different visual modules with the goal of generating a quantitative 3D reconstruction of the observed scene and to estimate the reconstruction errors.The integration is achieved in two steps. Firstly, several different visual modules analyze the scene in terms of a common data representation: planar patches are used by different visual modules to communicate and represent the 3D structure of the scene. We show how it is possible to use this simple data structure to share and integrate information from different visual modalities, and how it can support the necessities of the great majority of different visual modules known in literature. Secondly, we devise a communication scheme able to merge and improve the description of the scene in terms of planar patches. The applications of state-of-the-art algorithms allows to fuse information affected by an unknown grade of correlation and still guarantee conservative error estimates.Tests on real and synthetic scene show that our system produces a consistent and marked improvement over the results of single visual modules, with error reduction up to a factor of ten and with typical reduction of a factor 2–4.

A Comparison of Classifiers for Real-Time Eye Detection

We describe a system for detecting and tracking human eyes using a digital camera. The system uses the combination ofan active illumination scheme to detect eyes and an appearance-based object classifier to weed out spurious detections.We briefly describe the eye-detection mechanism and then we compare the performances of subspace Gaussian classifiers and support vector machines applied to this task.