Conservatism as a function of bag composition

Abstract

The first purpose of this bookbag and pokerchip experiment was to examine the influence of the sample size and the relative frequency of the red chips in the sample on the amount of conservatism. The second purpose was to replicate the results of D E S WART (1972), and to test his hypothesis that the slope B of the function: log Φ( T)= A+ B( r− b), is linearly related to log [ p r /(1− p r )], where p r represents the bag composition. The estimates of the Ss were transformed according to the method used by D E S WART (1972). The results were consistent with the results of D E S WART (1972) and showed (1) that neither the sample size nor the relative frequency in the sample influenced the amount of conservatism and (2) that B and log [ p r /(1− p r )] were linearly related. The data suggest, that the aggregation of the information is well predicted by Bayes' theorem, although the Ss react to [ p r /(1− p r )] in a very reduced way. The results are incompatible with the misaggregation hypothesis and the response bias hypothesis.