English

On the numerical approximation of minimax regret rules via fictitious play

Econometrics 2025-03-17 v1

Abstract

Finding numerical approximations to minimax regret treatment rules is of key interest. To do so when potential outcomes are in {0,1} we discretize the action space of nature and apply a variant of Robinson's (1951) algorithm for iterative solutions for finite two-person zero sum games. Our approach avoids the need to evaluate regret of each treatment rule in each iteration. When potential outcomes are in [0,1] we apply the so-called coarsening approach. We consider a policymaker choosing between two treatments after observing data with unequal sample sizes per treatment and the case of testing several innovations against the status quo.

Keywords

Cite

@article{arxiv.2503.10932,
  title  = {On the numerical approximation of minimax regret rules via fictitious play},
  author = {Patrik Guggenberger and Jiaqi Huang},
  journal= {arXiv preprint arXiv:2503.10932},
  year   = {2025}
}