July 8 Social Influence

Gael Le Mens, Professor (Catedràtic), Department of Economics and Business, Universitat Pompeu Fabra

Alexandros Gelastopoulos, Research Fellow, Institute for Advanced Studies in Toulouse

Synchronous session info:
Date: July 8, 2025
Start Time: 16:00 UTC (12:00 EST / 18:00 CET)
End Time:  17:20 UTC
Link: https://georgetown.zoom.us/j/99313919043?pwd=huivLfbwQDaS6ooRlhbTTm28bqQn9M.1
Meeting ID: 993 1391 9043
Passcode: 957 810

Dear TOM summer school participants!

In this session, we will review a set of models that aim to explain why people tend to hold beliefs and make choices like those with whom they interact.

In the first part of the session (taught by GLM), we will focus on settings in which agents learn about the ‘value’ of an option from their experience, the experience of others, or information passed to them by others. 

In the second part (taught by AG), we will ask under what conditions an intrinsically unattractive option can become and remain popular in the long term through social influence.

To prepare for the session, please try completing this assignment, consisting of two parts. In the first part, you will find the description of a simple social influence model, and you will be asked to reflect on some of the modeling choices and their meaning. In the second part, you will be asked to read a classic paper and similarly reflect on a model that it introduces.

References

Arthur, W. B. (1989). Competing Technologies, Increasing Returns, and Lock-In by Historical Events. The Economic Journal, 99(394), 116–131. https://doi.org/10.2307/2234208