Commitment and Belief Revision

I came across this working paper by Falk and Zimmermann while browsing the tentative program of a workshop I am attending in the summer. Like reading the information projection paper by Madarasz (2012), I was shocked to see that no similar experiments had been conducted in economics or psychology! Typical of Falk’s experiments, all treatments are extremely simple. Subjects are shown a jar and asked to estimate the number of peas in it. Estimation is of course incentivized. Mainly they are interested to see if commitment changes the way/extend people process information and revise their beliefs. The commitment is generated by writing down an initial estimate (which is payoff-irrelevant) on a piece of paper. It turns out that commitment has huge effect on information processing and belief revision. In short, committed subjects are more reluctant to incorporate additional information or revise their beliefs. What interests me more are two additional treatments with subtle differences. In one, subjects wrote down their estimates but showed them to no one, not even the experimenters. Yet such private commitment is sufficient to generate the main effect! (Falk and Zimmermann are working on explaining the underlying mechanism of this commitment effect and it seems that they lean on the social root?!) In another, subjects only raised their hands once they had an estimate. In this treatment, no commitment effect was observed, which actually appears a little peculiar to me. After all, how (and why) would writing down something to oneself be any different from determining something in one’s head? As I’ve always believed, given what we have learnt along the way, understanding how individuals make decisions is all about figuring out the boundary conditions – this is a nice demonstration of the idea.

[1]Falk, Armin, and Florian Zimmermann. Information processing and commitment. mimeo, 2016.
[2]Madarász, Kristóf. “Information projection: Model and applications.” The Review of Economic Studies (2011): rdr044.