Initial NFL Betting Analysis

As you all must know, I spend a lot of my spare time doing useless analysis.

But occasionally my statistical analysis can make me money. I spent so much time researching Big Ten college football teams that I've barely had time to look at NFL. I don't like betting NFL games. Mostly because both teams are very well figured out and the odds makers are much more accurate than college football. In College Football I have the edge because I can spend more time evaluating each team in a match up that the guy who has to handicap 60 games. But the only thing about NFL betting that really interests me is betting on regular season wins. Because sport books put out lines on all teams it is possible to look at each team compared to the strength of each team they face. Eventually you create a spreadsheet with each team and the expected wins of each team they play and that looks like this.

And now you can analyze each team compared to the teams they play. I'll do this analysis over the next few nights. A few drawbacks of this analysis are that; each opponent plays different teams and each team has a different strength of schedule which affects their line, the amount you have to risk to win $100 varies with each bet. I.E. right now you have to bet $135 on the lions winning 4.5 games to win $100, but you only have to bet 95 on the Lions winning less than 4.5 games to win $100. So the lines don't necessarily match up evenly.

But the only analysis that I have done is on some overall numbers, comparing predicted outcomes to last years actual outcomes.


The first row of this chart shows that teams are on average overvalued by an eighth of a win. There have to be equal amounts of wins and losses. The reason for this is that there are lots of casual bettors that will bet their team to win more games regardless of the O/U line.

The other noticeable thing about this chart is that there are a lot of teams that are expected to go over .500. This is possible and reasonable, but in order for this to happen there have to be a lot of above average teams and there have to be a good number of terrible teams. But the odds makers are predicting that there aren't. For last year to have 16 teams go over .500 there were 6 teams that achieved less than 5 wins. But this year the bookmakers expect 18 teams to go over .500 with only one team getting less than 5 wins. Either they're expecting all the teams under .500 to go 5-11 or 6-10 or people should start betting the unders.

Also only one team getting over 11 wins? Over the last 5 regular seasons there were an average of 4.6teams getting more that 11 wins a season. Maybe betting overs on some Superbowl favorites is in order.

Overall it appears that the odds makers are coming out pretty conservative. Last year there were 11 teams with over 11 wins or less than 5. Initial lines for this year have only 2 teams falling in those categories. Perhaps tomorrow I should also look at what the lines looked like going into last season.