Categorization is a core psychological process that is central to decision making. While a substantial amount of research has been conducted to examine individual categorization behavior, little is known about how the outputs of individual and group categorization may differ. Four experiments...

We present a new event-level predictor of comparative optimism: comparative optimism is larger for more socially undesirable events. A meta-analysis shows that event social undesirability predicts comparative optimism effect sizes reported in the literature, over and above the effects of other...