When Does Making Detailed Predictions Make Predictions Worse?
Kelly, T. F., & Simmons, J. P., When does making detailed predictions make predictions worse? Journal of Experimental Psychology: General, Forthcoming
15 Pages Posted: 26 May 2016 Last revised: 7 Sep 2016
Date Written: September 6, 2016
In this paper, we investigate whether making detailed predictions about an event worsens other predictions of the event. Across 19 experiments, 10,896 participants, and 407,045 predictions about 724 professional sports games, we find that people who made detailed predictions about sporting events (e.g., how many hits each baseball team would get) made worse predictions about more general outcomes (e.g., which team would win). We rule out that this effect is caused by inattention or fatigue, thinking too hard, or a differential reliance on holistic information about the teams. Instead, we find that thinking about game-relevant details before predicting winning teams causes people to give less weight to predictive information, presumably because predicting details makes useless or redundant information more accessible and thus more likely to be incorporated into forecasts. Furthermore, we show that this differential use of information can be used to predict what kinds of events will and will not be susceptible to the negative effect of making detailed predictions.
Keywords: Decision making, Forecasting accuracy, Accessibility, Prediction Specificity
Suggested Citation: Suggested Citation