No Reduction in Hindsight Bias after Complete Information and Repeated Testing

In hindsight, people often claim to have known more than they actually did. This finding has been termed hindsight bias. We report two hindsight-bias experiments which yielded converging results with different methods. All participants first estimated numerical values as answers to difficult knowledge questions, were later given the solutions, and were finally asked to recall their first estimates. In an attempt to reduce the typically found bias, the participants of one group in Experiment 1 were informed in advance about the experimental design and the bias phenomenon, while the participants of another group were not. In Experiment 2 all participants received at the end individual feedback about their recall performance and were then subjected to the same experimental procedure again, twice in succession. The amount of hindsight bias, however, remained unaffected by either of these two manipulations. These findings support automatic processes as explanation for the observed bias and dismiss motivational accounts.