Throughout our years of watching football together, my father and I have developed a little tradition. Whenever we are watching Liverpool (his team) and they go two goals up, he will lean forward in his seat and sigh ‘I hate two goal leads’. While I was in a different part of the country at the time, I would wager a healthy amount that he said this to my mother in my absence last Sunday just after the Reds scored their second against Manchester City.
Two things have always puzzled me about this.
One, it is an entirely illogical train of thought. As Robbie Butler has attested to previously on the At the Margin podcast, the most common results in football are 1-0, 1-1, 0-1, 0-0. All of these results can be altered by just one goal. Accordingly, accumulating a two-goal lead at any point in a match massively increases the probability of a team winning.
The second thing which puzzles me about this tradition of ours is that I do it myself when watching my own team, Arsenal.
The reason for this is probably simple enough. It could be that the thought of our teams failing to win after already establishing a lead is so painful that we overestimate the likelihood of it occurring simply because we are worried about it. I do something very similar when thinking about the probability of seeing a vampire late at night. Given that I work with data, I was interested in seeing just how irrational a fear this was. It turns out, very.
Looking at 1,140 Premier League fixtures over 3 full seasons I looked at instances where teams were 2 goals up at half time (145) and then looked at the number of times those teams failed to win the fixture (12). Of those 12 times, 7 ended as draws, and 5 ended in a loss. This means teams fail to win matches where they have gone two-nil up at half time a little over 8% of the time.
Interestingly, however, there is a bit of deviation in the prevalence of this happening depending on whether the leading team is home or away. In the case of the former, there are 85 instances of a home team being two-nil up at half time. Of these 85, 80 ended in a home win, 3 ended in a draw, and just 2 ended in a loss for the home side. Meaning when two-nil up at half time, the home team goes on to win the fixture just over 94% of the time.
To revise on a previous statement in this post, I now find a third thing puzzling about my attitude towards two-goal leads. The results of my own analysis on the topic, which confirm that they mostly result in wins for the leading team, have done nothing to suppress me fear of Arsenal throwing them away.

RSS Feed