We use trade data from an online game economy to test the 'dopaminergic reward prediction error' (DRPE) hypothesis: upon buying a game item at a price which is obviously too low, a player should become more active in the trading market. We find that players are more willing to buy goods in the in-game market after such an trade incident. Hence, the effect predicted by the DRPE model is visible. Yet, contrary to the prediction of DRPE, the magnitude of the prediction error does not have any effect on the post-error trading activity
