What effect does repeated play have on reputation building? The literature on international relations remains divided on whether, when, and how reputation matters in both interstate and intrastate conflict. We examine reputation building through a series of incentivized laboratory experiments. Using comparative statics from a repeated entry-deterrence game, we isolate how incentives for reputation building should change as the number of entrants changes. We find that subjects in our experiments generally build reputations and that those investments pay off, but we also find that some subjects did not react to incentives to build reputation in ways our model had predicted. In order to explain this, we focus on the heterogeneity of preferences and cognitive abilities that may exist in any population. Our research suggests that rational-choice scholars of international relations and those using more psychologically based explanations have more common ground than previously articulated.

While most existing theoretical and experimental literatures focus on how a high probability of repeated play can lead to more socially efficient outcomes (for instance, using the result that cooperation is possible in a repeated prisoner's dilemma), this paper focuses on the detrimental effects of repeated play--the ``Dark Side of the Future". I study a resource division model with repeated interaction and changes in bargaining strength. The model predicts a negative relationship between the likelihood of repeated interaction and social efficiency. This is because the longer shadow of the future exacerbates commitment problems created by changes in bargaining strength. I test and find support for the model using incentivized laboratory experiments. Increases in the likelihood of repeated play leads to more socially inefficient outcomes in the laboratory.