We've not had a proposition bet for a while, so here's a new one for you. We're going to pick a large number of games at random and, based on the half-time score in each, I'll pledge to bet on the team that's scored the greater number of behinds whether they be the raging favourite or the deserving underdog. It both teams have scored the same number of behinds at the main break or if the game ends in a draw, the bet is a push and neither of us need reach into our pockets. Otherwise, I collect if the team that had scored the greater number of behinds at the half goes on win, and you win if the team that had scored the lesser number of behinds at the half goes on win. Simple.
From previous analyses we know that superior behind accumulation is rarely decisive in a contest; almost always, it's all about the goals. But, there's surely some information content, however small, in the relative number of behinds that the competing teams have scored, so I'm going to offer you a price of $2.20 if you'll take my wager. Sounds attractive, surely.
The truth is that the team that has scored the greater proportion of behinds at the main break goes on to win a startling 59.5% of contests in which the game ends with a winner and in which there's a team that leads on the behind count at half time (which was true for about 86% of the games in 2010). So, $2.20 is nowhere near a fair price - you'd want about $2.45 to $2.50 to be at approximately breakeven based on the results for the entirety of season 2010.
If we'd wagered instead based on the behind proportions at quarter-time you'd have wanted about $2.35 as the proportion of teams that lead on behinds at the end of the first quarter went on to win about 57.5% of games that ended with a winner and in which there was a team that led on the behind count at quarter time (which was true for about 84% of the games in 2010).
Basing the wager on the third quarter score you should be seeking about $3.30 as almost 70% of teams that lead on behinds at the end of the third quarter went on to win games in which there was a clear winner and a clear behind leader at three-quarter time (which was true for about 94% of the games in 2010).
Lastly, for completeness only, teams that registered the greater proportion of behinds by the end of the final quarter were the winners in 69% of games in which there was a clear winner and a clear behind leader at three-quarter time (which was true for about 95% of the games in 2010).
So, the relative number of behinds that the two competing teams have scored at any point in a game is actually a reasonable indicator of which team is most likely to win, moreso as the game progresses.