Fernando Diaz-Diaz
fernandodiazdiaz.bsky.social
Fernando Diaz-Diaz
@fernandodiazdiaz.bsky.social
Physicist by training, mathematician by work.
Assistant Prof. at the University Carlos III (Madrid). Currently exploring the mathematical properties of signed networks.
Also interested in statistics, international relations, and mathematical finance.
That said, my main reference when thinking about communities is precisely your work on descriptive vs inferential approaches that you mention, so I will probably agree with you on most aspects :)
July 11, 2025 at 9:05 AM
But at the same time, I think it's nice to keep in mind that there are situations where looking at disconnected components as a extreme case of communities can make sense, especially if the objective of the study is not to analyze data.
July 11, 2025 at 9:01 AM
I completely agree, mixing two conceptualizations of community can lead to problems, because minimizing cut-sets and maximizing likelihoods are based on very different assumptions.
July 11, 2025 at 9:01 AM
To be clear, I agree that interpreting community detection as a maximum-likelihood problem is a more powerful approach to understand complex datasets. My point is that, from a mathematical (not statistical) point of view, the other vision can be insightful too.
July 11, 2025 at 8:42 AM
In fact, I would say the pure-math approach to communities tends to understand them as "almost disconnected" regions (partitions with a small cut-set), and this perspective has led to nice results (for example the Cheeger inequalities, the spectral clustering algorithms, perturbative methods, etc).
July 11, 2025 at 8:42 AM
I think the interpretation of communities as network partitions with a small cut-set is useful in certain areas. Ofc, claiming that this conceptualization of community is statistically meaningful is problematic, but as a descriptive concept I think it's ok.
July 11, 2025 at 8:42 AM
Ojalá un debate entre @lavacaesferica.bsky.social, @juanjosemillas.bsky.social y Arsuaga a raíz de la frase "si no conocemos las interacciones que ocurren en su interior, tampoco seremos capaces de predecir el comportamiento del sistema".
June 24, 2025 at 5:19 PM