Competitive Balance in European Football and US Team Sports, the Role of the Referee and the Scoring Context Loek Groot (USE) Gijon, 9 May 2008

2 Structure Main findings CB in European football versus US Poisson process of goal scoring Scoring context and CB The role of the referee Ties versus overtime CB in England in 20th century Conclusions

3 Main findings An impartial fallible referee is conducive to CB, so fifth official monitoring the match reduces CB. Low scoring context of football is conducive to CB. This largely explains the highly artificial measures in US to maintain CB and suggests a trade-off between entertainment (number of goals) and suspense (CB). Ties instead of overtime is conducive to CB. Optimal CB in a closed league is higher than in an open league.

4 EU versus US, Natural Competitive Balance EuropeUS Low scoring context: CB higher high scoring context: CB lower Role referee: CB higherRole referee: CB lower Ties: CB higherOver time: CB lower Open league (relegation & promotion): CB* lower Closed league: CB* higher

5 Poisson process of goal scoring The chance on outcome (x, y) is simply P(X=x)*P(Y=y).

6 Scoring context and CB

μ↑ ν → Scoring context, CB and relative team inequalities

8 The role of the referee

9 Ties versus overtime WEtie = PwinR + Ptie/2 WEOT = PwinR + Ptie(PwinOT + PtieOT/2) Assume for simplicity that under the practice of overtime, a game that ends in a tie in regular time is replayed in full. For the replay, the Poisson scoring parameters do not change and therefore PwinOT is equal to PwinR and Ptie is equal to PtieOT. The difference in winning equivalents can then be written as: ∆ = WEtie – WEOT = Ptie(Ploss - Pwin)/2 > 0

10 CB in England in 20th century

11 Conclusions Natural level of CB in European football higher than in US team sports Optimal level of CB in EU lower than in US Necessity for a special exemption under antitrust law much less in EU, or burden of evidence for such an exemption much higher Need for special artificial measures to maintain CB much less in EU