We design an experiment to study investment behavior in different repeated contest settings, varying the uncertainty of the outcomes and the number of participants in contests. We find decreasing over-expenditures and a higher rate of ‘dropout’ in contests with high uncertainty over outcomes (winner-take-all contests), while we detect a quick convergence toward equilibrium predictions and a near to full participation when this type of uncertainty vanishes (proportional-prize contests). These results are robust to changes in the number of contestants. A learning parameter estimation using the experience-weighted attraction (EWA) model suggests that subjects adopt different learning modes across different contest structures and helps to explain expenditure patterns deviating from theoretical predictions.

我们设计了一个实验来研究在不同的重复比赛环境中的投资行为，从而改变结果的不确定性和比赛参与者的数量。我们发现在结果不确定性较高的比赛（获胜者通吃比赛）中，超额支出减少且“辍学”率较高，而当我们发现这种不确定性时，我们会迅速趋向均衡预测并接近完全参与消失（比例奖竞赛）。这些结果对于改变参赛者人数是有力的。使用经验加权吸引力（EWA）模型的学习参数估计表明，受试者在不同的竞赛结构中采用不同的学习模式，并有助于解释偏离理论预测的支出模式。