Spillover Effects in Contests with Heterogeneous Players - Evidence from European Football

Abstract

This paper analyzes spillover effects from previous matches against the future champion of a league. Using data from 78,264 European football games, the empirical results from a matching method show that favourites in the current match gain significantly fewer points after a match against the future league champion. By contrast, underdogs benefit from such a match, as they gain significantly more points. By considering shadow effects in the analysis, these results suggest that favourites put more effort into the match against the future champion and lower their effort level in the next match, which explains the negative spillover effects. As there are no significant shadow effects for underdogs, the positive spillover effects might be caused by positive ‘learning-by-doing’ effects. A subsequent logit regression using betting odds as control variables confirms the existence of the observed spillover effects.