RESUMO
Prior research has demonstrated that Americans massively overestimate how much their home state has contributed to US history. Why does such collective overclaiming occur? We argue that although self-serving biases undoubtedly influence overclaiming, non-motivated factors, such as a failure to consider the contributions of other states, also play a large role in overclaiming effects. In the current studies, subjects read descriptions of territories within a fictitious country and evaluated how much a territory within that country contributed to its history. Experiment 1 showed that overclaiming of responsibility increased as more territories were added to the country. Experiments 2 and 3 showed that requiring subjects to explicitly consider all territories reduced estimations of responsibility. Experiment 4 showed that people provided higher ratings of responsibility when more details were provided about the territory. Finally, Experiment 5 showed that retrieval fluency did not affect overclaiming. We conclude that support theory - based on the availability of content - provides a strong explanation for why the collective overclaiming of responsibility occurs, with both theoretical and practical implications.