The research project is implemented in the framework of H.F.R.I call “Basic research Financing (Horizontal support of all Sciences)” under the National Recovery and Resilience Plan “Greece 2.0” Funded by the European Union - NextGenerationEU (H.F.R.I. Project Number: 016636)

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Themis: Modeling, Measuring and Mitigating Bias in Online Information Platforms

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Themis: Modeling, Measuring and Mitigating Bias in Online Information Platforms

We live in a world where most of our information and communication needs are satisfied by online information platforms (OIPs) such as Search Engines and Social Networks and Media. These platforms play an important role in shaping the opinions and guiding the decisions of users for simple or important matters. Their operation relies on sophisticated machine learning and AI algorithms for filtering, ranking and recommendations, trained on massive amounts of data collected by the behavior and the contributions of users online. However, the function of these platforms can be compromised due to the presence of bias in the behavior of human users, but also in the decisions of the automated AI algorithms used by OIPs. These biases can result in unfair decisions by the AI algorithms, in recommendations of content, ranking of results, or the profiling of the users, as well as the emergence of echo chambers and filter bubbles in social networks.

The goal of the Themis project is to develop a formal framework for modeling, measuring, and mitigating bias online.

Themis will consider different types of bias in online information providers such as search engines and social networks and media. It will provide novel definitions of bias and fairness for problems such as opinion formation and community detection, and provide models for the emergence of bias in social media. It will also perform measurements of bias on datasets. The project is structured along three axes aligned with the three goals above.

Modeling Bias

The goal in this axis is to define models that capture the different aspects of bias and fairness and define metrics for quantitatively measuring bias and fairness in the OIPs. We will also consider models for understanding the emergence of bias in the OIPs. The focus will be on defining bias in formation processes, and communities in social networks.

Measuring Bias

The goal in this axis is to measure bias in practice in OIPs. The focus will be on Large Language Models (LLMs) which are currently being used for answering questions, retrieving information, and generating new content. The focus of the work will be on detecting stereotyping behavior of LLMs with respect to gender, race or religion.

Mitigating Bias

The goal in this axis is to define fair algorithms that mitigate bias. The focus will be again on making opinion formation processes and community detection algorithms fair.

Project information:

Team

Panayiotis Tsaparas

Panayiotis Tsaparas

Principal Investigator
Associate Professor, University of Ioannina, Department of Computer Science & Engineering
Panagiotis Papadakos

Panagiotis Papadakos

Research Assistant
Post-doctoral Researcher at the Institute of Computer Science of the Foundation for Research and Technology - Hellas and the University of Ioannina, Department of Computer Science & Engineering, Greece
Christos Karanikolopoulos

Christos Karanikolopoulos

Research Assistant
MSc student at University of Ioannina, Department of Computer Science & Engineering, Greece
Glykeria Toulina

Glykeria Toulina

Research Assistant
MSc student at University of Ioannina, Department of Computer Science & Engineering, Greece
Glykeria Toulina

Spyridon Tzimas

Research Assistant
Undergraduate student at University of Ioannina, Department of Computer Science & Engineering, Greece Phd at Mathematics, University of Ioannina, Greece
Christos Gartzios

Christos Gartzios

Research Assistant
Undergraduate student at University of Ioannina, Department of Computer Science & Engineering, Greece
Evaggelia Pitoura

Evaggelia Pitoura

Advisory Board
Professor, University of Ioannina, Department of Computer Science & Engineering
Aristides Gionis

Aristides Gionis

Advisory Board
Professor at KTH Royal Institute of Technology, Sweden
Carlos Castillo

Carlos Castillo

Advisory Board
Professor at Universitat Pompeu Fabra, Spain
Stavros Sintos

Stavros Sintos

Advisory Board
Assistant Professor at University of Illinois Chicago, U.S.A.
Panagiotis Papapetrou

Panagiotis Papapetrou

Advisory Board
Professor at Stockholm University, Sweden