Human-environment interactions in group foraging behavior
Indiana University Department of Psychological and Brain Sci
Indiana University Department of Psychological and Brain Sciences
Last modified: May 4, 2006
We have previously reported empirical resource matching results for a human group foraging task in a virtual world (Goldstone & Ashpole, 2004; Goldstone, Ashpole, and Roberts, 2005), and we subsequently developed an agent-based foraging model, EPICURE, that accurately modeled the empirical results and made several testable predictions (Roberts and Goldstone, in press). In the current paper, we compare the model's predictions to new human group foraging results. We examine the effects of high and low levels of Gaussian variance for two patchily-distributed resource pools, high and low travel distances between pools, and three resource pools when the resources and other foragers are visible and invisible, respectively. In agreement with our spatial resource undermatching explanation derived from EPICURE simulations (Roberts and Goldstone, in press), participants switched pools significantly less frequently in the low variance condition than the high variance condition, and the low variance condition also led to significantly less wealth disparity, as measured by the Gini coefficients. Consistent with pigeon foraging results from Baum and Kraft (1998), the high travel condition also shows significantly less pool switching than the low travel condition; however, the improvement in group resource matching for the high travel condition was not as pronounced as EPICURE's predictions. Finally, the three resource pool conditions showed significant resource undermatching in both visibility conditions, thereby extending our previous undermatching results for two resource pools and consistent with EPICURE's predictions and the Sokolowski et al. human foraging results for three resource pools (2004). Although EPICURE successfully predicted many of the empirical results, we also explore several shortcomings of the model.
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