What Happens in Frankfurt Stays in Frankfurt

I am going to be in Frankfurt for a few days for a workshop on metric networks that I coorganized.

What Happens in Oxford Stays in Oxford

I am off to Oxford to spend most of the next few weeks. I'll also have a short embedded trip to Frankfurt and will be heading to Glasgow after my time in Oxford.

RIP Barry Wellman (1942–2024)

I'm very sad to hear about sociologist Barry Wellman's death.

He was one of the people who welcomed me warmly to the Sunbelt community (though he did make a point to inform me, with much spittle flying in the process, of course, that the Dodgers shouldn't have left Brooklyn).

I figured (but never officially knew) that Barry had been sick for a while, given his sudden lack of activity starting a couple of years ago on Facebook and SOCnet after always making a point of stressing that the point of such social gathering spaces (including social media) was to be very active, so he always purposely did that.

(h/t through the SOCnet mailing list)

RIP Martin Mull (1943–2024)

Comedic actor, musician, and painter Martin Mull dies yesterday.

I found out about him via the song "Dueling Tubas", which I first learned about in Physics 2a through an acoustics demo by now-Nobel Laureate David Politzer.

My musically-inclined classmates were in emotional pain.

RIP Willie Mays (1931–2024)

The legendary Willie Mays died today. Mays was the oldest living baseball Hall of Famer; he took the mantle in 2021 when Tommy Lasorda died. You can see Willie Mays' statistics on this page.

I believe that Luis Aparicio is now the oldest living baseball Hall of Famer.

"Emergence of Polarization in a Sigmoidal Bounded-Confidence Model of Opinion Dynamics"

A paper of mine was just published in final form. Here are zome details.

Title: Emergence of Polarization in a Sigmoidal Bounded-Confidence Model of Opinion Dynamics

Authors: Heather Z. Brooks, Philip S. Chodrow, and Mason A. Porter

Abstract: We study a nonlinear bounded-confidence model (BCM) of continuous-time opinion dynamics on networks with both persuadable individuals and zealots. The model is parameterized by a nonnegative scalar \gamma, which controls the steepness of a smooth influence function. This influence function encodes the relative weights that individuals place on the opinions of other individuals. When \gamma = 0, this influence function recovers Taylor's averaging model; when \gamma \rightarrow \infty, the influence function converges to that of a modified Hegselmann--Krause (HK) BCM. Unlike the classical HK model, however, our sigmoidal bounded-confidence model (SBCM) is smooth for any finite \gamma. We show that the set of steady states of our SBCM is qualitatively similar to that of the Taylor model when \gamma is small and that the set of steady states approaches a subset of the set of steady states of a modified HK model as \gamma \rightarrow \infty. For certain special graph topologies, we give analytical descriptions of important features of the space of steady states. A notable result is a closed-form relationship between graph topology and the stability of polarized states in a simple special case that models echo chambers in social networks. Because the influence function of our BCM is smooth, we are able to study it with linear stability analysis, which is difficult to employ with the usual discontinuous influence functions in BCMs.

What Happens in Warsaw Stays in Warsaw

I am heading to Warsaw to participate a couple of days in the WAW 2024 conference. This is my first trip to Poland in several years, and unfortunately it's going to be very brief.