Reference-Dependent Preferences : Evidence from Marathon Runners

Models of reference-dependent preferences propose that individuals evaluate outcomes as gains or losses relative to a neutral reference point. We test for reference dependence in a large dataset of marathon finishing times (n = 9,524,071). Models of reference-dependent preferences such as prospect theory predict bunching of finishing times at reference points. We provide visual and statistical evidence that round numbers (e.g., a four-hour marathon) serve as reference points in this environment and as a result produce significant bunching of performance at these round numbers. Bunching is driven by planning and adjustments in effort provision near the finish line and cannot be explained by explicit rewards (e.g., qualifying for the Boston Marathon), peer effects, or institutional features (e.g., pacesetters). We calibrate a simple model of prospect theory as well as other models of reference dependence and show that the basic qualitative shape of the empirical distribution of finishing times is consistent with parameters that have previously been estimated in the laboratory