Renowned network scientist and creator of InfoMap (probably the world’s best community detection algorithm for complex networks), Martin Rosvall, is visiting Copenhagen. And I’ve managed to convince him to visit DTU to give a talk!
Martin is an associate professor at the department of physics at the university of Umeå (Sweden). He’s an accomplished author of many highly cited papers, and a great speaker. Thus, I strongly recommend you come see his talk.
The details are below:
- Time: Wednesday December 7, 11:00am
- Place: Technical University of Denmark. Building 321, 1st floor Lab Space.
- Title: Maps of sparse Markov chains efficiently reveal community structure in network flows with memory
- Abstract: To better understand the flows of ideas or information through social and biological systems, researchers develop maps that reveal important patterns in network flows. In practice, network flow models have implied memoryless first-order Markov chains, but recently researchers have introduced higher-order Markov chain models with memory to capture patterns in multi-step pathways. Higher-order models are particularly important for effectively revealing actual, overlapping community structure, but higher-order Markov chain models suffer from the curse of dimensionality: their vast parameter spaces require exponentially increasing data to avoid overfitting and therefore make mapping inefficient already for moderate-sized systems. To overcome this problem, we introduce an efficient cross-validated mapping approach based on network flows modeled by sparse Markov chains. To illustrate our approach, we present a map of citation flows in science with research fields that overlap in multidisciplinary journals. Compared with currently used categories in science of science studies, the research fields form better units of analysis because the map more effectively captures how ideas flow through science.
sune lehmann 