Panayiotis Zaphiris, Giorgos Zacharia, Andrew Laghos
Participatory design will be implemented as a four step process: (a) Build bridges with the intended users (b) Map user needs and suggestions to the system (c) Develop a prototype (d) Integrate...
Participatory Design of Interactive computer-based Learning Systems (2009)
Panayiotis Zaphiris Phd, Giorgos Zacharia
We present an iterative evaluation methodology (as part of a participatory design methodology) employed in an online course for learning Modern Greek. Unlike other educational technology evaluation...
Website Content Accessibility of the Cyprus Domain (2009)
Panayiotis Zaphiris, Giorgos Zacharia
Abstract. This paper extends previous studies that investigated the accessibility of different web sites of specific content, to an analysis of the whole web of a specific country (Cyprus). To our...
Iterative Evaluation of a Participatory Designed Online Course (2008)
Panayiotis Zaphiris, Giorgos Zacharia
We present an iterative hybrid formative evaluation methodology incorporated in a Participatory Design process for an online multimedia course in Modern Greek. Our hybrid evaluation incorporates...
PERSONALIZED RECOMMENDATIONS BY LEARNING FROM RELATED DATA (2008)
In this paper we investigate how to incorporate preference ranking data available from related individuals to improve individual specific preference learning models. We present regularized learning...
Giorgos Zacharia, Tomaso Poggio
In this work we investigate how to incorporate data available from seemingly unrelated tasks to improve task specific learning models.
Supervised Information Retrieval for Text and Images (2008)
Ros Kyriakides, Giorgos Zacharia
The Problem: To perform retrieval of images. We will use the captions of the images that appear in news articles. Given a news story that appears in a news article, our goal is to select an...
Measuring Internet Audiences and Usability of an Online Course (2007)
Panayiotis Zaphiris, Giorgos Zacharia
In this paper, we attempt to outline a variety of methods used to construct a richer conception of the audience of a modern Greek online course. First an analysis of the design methodology employed...
Giorgos Zacharia, Ros Moukas, Robert Guttman, Pattie Maes
In this paper we combine ideas of electronic commerce and mobile environments in agent-based transaction systems. Shopping for goods and services can be highly time-consuming. Although there is...
Economics of Dynamic Pricing in a Reputation Brokered Agent Mediated Marketplace (2001)
Giorgos Zacharia, Ros Moukas, Petros Boufounos, Pattie Maes
We study the microeconomic effects in a reputation brokered Agent mediated Knowledge Marketplace, when we introduce dynamic pricing algorithms. We study the market with computer simulations of...
Website content accessibility of 30,000 cypriot web sites (2001)
Panayiotis Zaphiris, Giorgos Zacharia
Abstract. This paper extends previous studies [10, 12, 13] that investigated the accessibility of different web sites of specific content and context to an analysis of the whole web of a specific...
Usability Evaluation of an OnLine Modern Greek Language Course (2001)
Panayiotis Zaphiris, Giorgos Zacharia
Abstract. In this paper, a set of user-centered evaluation methods used to construct a richer conception of the audience of an online Modern Greek online course is presented. First an analysis of the...
Economics of Dynamic Pricing in a Reputation-Brokered Agent-Mediated Marketplace (2000)
Giorgos Zacharia, Theodoros Evgeniou, Pattie Maes
We describe an Agent Mediated marketplace, with dynamically changing reputation ratings. In this marketplace, the seller reputations are updated in a collaborative fashion based on the performance of...
Trust management through reputation mechanisms (2000)
This paper proposes reputation mechanisms that rely on collaborative ratings and personalized evaluation of the various ratings assigned to each user. Reputation is usually defined as the amount of...
Collaborative Reputation Mechanisms in Electronic Marketplaces (1999)
Giorgos Zacharia, Alexandros Moukas, Ros Moukas, Pattie Maes
The members of electronic communities are often unrelated to each other, they may have never met and have no information on each other's reputation. This kind of information is vital in...
Evolving a Multi-agent Information Filtering Solution in Amalthaea (1997)
Alexandros Moukas, Giorgos Zacharia
Amalthaea is an evolving, multiagent ecosystem for personalized filtering, discovery and monitoring of information sites. Amalthaea's primary application domain is the World-Wide-Web and its...