Beyond research and teaching: on the role of universities in our society

(a thread on Mastodon U. Twente.)

In the essay The Fragmentation of Truth danah boyd makes the following important point: To combat increasing polarisation in our society, we need to rely on organisations that actively and intentionally let people with fundamental differences work alongside one another.

Boyd mentions the military as an example of an organisation that brings together people from different social backgrounds and political views to work on a common goal. To “intentionally bridge gaps in the social graph, to intentionally connect people and communities.”

I see schools and universities as another major power to combat polarisation in our society. Our university brings together people from different backgrounds, politcal views and cultures. Creating a sense of common purpose and a sense of a university community is important to fight polarisation and populism in our society.

That’s why our campus, our study associations, our sport, cultural and other student associations, are so important. That’s also why we need democratic institutions and self-government. They do not only shape our university now, they shape our future society.

We need to work harder to shape our universty as a community. If international students feel disconnected, then we completely failed as a university, no matter how excellent our educational programs are. This U-Today story, International bachelors: psychological and social problems, breaks my heart: (“One in three non-European bachelors had study problems in the previous academic year due to psychological, medical or social circumstances.”)

Danah boyd discusses in depth how platforms like Youtube and Facebook harm our society; how they directly threaten the important role that schools and universities play in creating a peaceful society. From this view point it is clear: Youtube should not be the primary channel for our online lectures; Facebook should not be the primary channel for our events.

Finally, services like search engines may be harmful, however well-intended and well-implemented. I find this hard to say as an Information Retrieval researcher, but search is easily manipulated, and you might not want powerful search in some applications. Boyd’s concept of ‘data voids’ is really insightful. Maybe we should teach students about search engine optimization in our courses too… #FIR

Whom to Follow on Mastodon?

Recommending Users: Whom to Follow on Federated Social Networks

by Jan Trienes, Andrés Torres Cano, and Djoerd Hiemstra

To foster an active and engaged community, social networks employ recommendation algorithms that filter large amounts of contents and provide a user with personalized views of the network. Popular social networks such as Facebook and Twitter generate follow recommendations by listing profiles a user may be interested to connect with. Federated social networks aim to resolve issues associated with the popular social networks – such as large-scale user-surveillance and the miss-use of user data to manipulate elections – by decentralizing authority and promoting privacy. Due to their recent emergence, recommender systems do not exist for federated social networks, yet. To make these networks more attractive and promote community building, we investigate how recommendation algorithms can be applied to decentralized social networks. We present an offline and online evaluation of two recommendation strategies: a collaborative filtering recommender based on BM25 and a topology-based recommender using personalized PageRank. Our experiments on a large unbiased sample of the federated social network Mastodon shows that collaborative filtering approaches outperform a topology-based approach, whereas both approaches significantly outperform a random recommender. A subsequent live user experiment on Mastodon using balanced interleaving shows that the collaborative filtering recommender performs on par with the topology-based recommender.

This paper will be presented at the 17th Dutch-Belgian Information Retrieval workshop in Leiden on 23 November 2018

[download pdf]

Welcome to REDI

Welcome to Research Experiments in Databases and Information Retrieval (REDI)! The theme of this year’s course is: Recommendation in federated social networks. Federated social networks consist of multiple independent servers that cooperate. An example is Mastodon, a free open source implementation of a micro-blogging social network that resembles Twitter. Unlike Twitter (or Facebook for that matter), nobody has a complete view of all accounts and posts in a federated social network. We will address two research problems: 1) How to implement recommendations using only local knowledge of the network? and 2) How to evaluate your system in such a highly dynamic environment?

We are the first University of Twente course with a public Canvas syllabus. Of course, we will appropriately use Mastodon to communicate about REDI. Please make an account on and follow the hash tag #REDI. Use the hash tag in questions and toots about the course.