Why "Shock" Results Should Be Expected
NFL and football fan. I've seen my two favourite sides, Stoke and the San Diego Chargers play at the new Wembley....and both lost.
As we head towards football season 2012-2013, today on the blog Mark Taylor takes a look back at Euro 2012 and tells us why we shouldn't be so surprised when underdogs upset short priced favourites.
Ask most people for their views about the likely outcome of a football match and the answers you receive will most probably carry a high degree of confidence. "Team A/B will win" or occasionally a draw will be the preferred choice. The reality is that for most professional sports, certainty is never on the menu. In Euro 2012 for example eventual winners, Spain had around a 78% chance of beating the tournament's worst team, Ireland. So even in apparent mismatches, the favourites are very likely to win, but the result is not an inevitable and foregone conclusion.
Games at the recent Euros went largely to form. Pre tournament favourites, Spain won convincingly in the final, although Italy's reduction to 10 men when already trailing inflated the eventual margin of victory.Upset results were hard to find over the 31 matches and a run of predictable results in high profile tournaments tends to reinforce the erroneous belief in the overwhelming supremacy of favoured teams.
The Danish Example
Probably the biggest upset at the Euros was Denmark's opening group game defeat of the quietly fancied Dutch side. As make weights in the tournament's Group of Death, the Danes were expected to trail in last behind their three more fancied opponents, but instead they gave themselves a shot at qualification with a slender 1-0 win.
Holland were strong pre game favourites and in light of the predictability of the rest of the tournament and the apparently overwhelming in running superiority of the Dutch side (they outshot Denmark by 32 attempts to 8) it is easy to dismiss this result as a massive abberation. However, this kind of "upset" is to be expected.
Before kickoff, the consensus opinion made the Dutch about a 62% chance compared to 15% for Denmark. Those numbers seem reasonable. The Dutch went into the tournament FIFA ranked 4th around 200 ranking points clear of the Danes in 8th and difference in FIFA points between teams is a reasonable predictor of future results. So the Dutch had every right to be favoured, but the Danes' 15% chance of winning was only slightly more unlikely than someone rolling a six on one roll of a die. Therefore a Danish win was not precluded as an outcome.
The opening and as it turned out only goal of the game arrived for Denmark after 24 minutes and with it the underdogs saw their chances of winning the match catapult to about 45%. So the chances of an upset win were now slightly less than those of rolling any three chosen numbers on one roll of a fair six sided die.
The All Important First Goal
And what of the chances of Denmark scoring the important first goal? Again it was less likely than not, but not overwhelmingly so. A team's chances of scoring the opening goal, if there is one, is directly related to the proportion of the total number of goals that team will score in that particular matchup.
The pre game odds indicated that Denmark would expect to average about 0.75 goals against Holland on neutral turf and concede about 1.75 goal. So they would score about 30% of the goals and therefore, 30% of the opening goals. Again we can model the event with a die, the Danes would score first at roughly the same rate you would expect to roll one of two selected numbers on one die roll.
More Than A Matter Of Shots
Superficially the best in game evidence for Denmark's win being a huge shock is the shot differential of 32-8 in favour of the Dutch. However, outlandish numbers such as these are extremely rare even when favourites trail. In the last six completed English Premiership seasons only Chelsea and Manchester United against Stoke and Fulham respectively have outshot the Dutch total against Denmark.
Underdogs who lead should expect a response from their opponents, but it will hardly ever be on the level seen in the Dutch game. The abberation was not that Denmark's goal remained intact, but that Holland managed to produce such a large number of goal attempts.
Shots from trailing sides on average do become more numerous, but they also become more speculative as the game dynamics change with the leading team concentrating more on defence than attack. Of the 32 Dutch shots, 11 had chances ranging from 1 in 20 to 1 in 70 of ending up in the net judged on the area of the pitch from which they were attempted. Taken as a whole the likelihood of all 32 shots drawing a blank was in the region of 1 in 40. Slim, but hardly vanishingly small.
To summarize, underdogs in a low scoring sport such as football can have a significant, but often overlooked chance of winning. The opportunity to boost their chances of success by scoring first can also be significant and the barrage of shots they then face may be more numerous, but are on average much less potent. So always try to think in terms of chances rather than being seduced into imagining favoured certainties reinforced by a recency bias.
Read more of Mark's work on his The Power Of Goals blog
And follow Mark of Twitter: @MarkTaylor0
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Yes i am shock the chances of an upset win were now slightly less than those of rolling any three chosen numbers on one roll of a fair six sided die. ____________________ sports equipment