NFL Season Win Totals: The Luck Index
August 07, 2007
No matter how you slice it, luck plays a large role in the win-loss records of many NFL teams. A missed or made FG, a key injury and a turnover here or there can easily turn a 10-6 team into a 6-10 one and vice-versa.
The Betting Doctor's Luck Index
I have reviewed 2006 for the results in three areas that I consider to be primarily based on luck:
1. Games Lost by Starters due to Injury
2. Turnover Margin
3. Net Win/Loss Record in "Close Games" (i.e. final margins of a TD or less)
Now I can already hear you saying that the above things are not lucky and perhaps even predictable. Some teams might have better off-season training and a great strength and conditioning coach. Maybe they play on a grass football-only home field without dirt and astroturf and seams and are thus less injury-prone. Perhaps aggressive D's and young/poor QB'ing create turnovers. And well coached veteran teams with great placekickers win the close ones.
I still think luck is by far the biggest factor in injuries. If you have read my article on "turnover turnaround" you know that you can make a lot of money by betting on short term turnover differences to balance out. There are also many games where a break here or there can change the final result.
The Lucky and the Unlucky
In order to create my index, I have ranked each team from first to worst on the above three categories. I then added up each team's three ranking numbers. Finally, I ranked those from 1 to 32. I created the index like a golf score so the team with the lowest score is the unluckiest and vice-versa. My thinking is that luck will revert to the mean and the unluckiest teams will increase their wins this year, while the lucky teams win totals will drop. Here is the alphabetical listing of my "Luck Index":
Putting it all Together
Let me give you some idea of the range of difference along these three scales. Cleveland finished "first" in injuries with 83 lost games by injured starters while Dallas had a measly 8. Turnover margin went from the -23 of the Raiders to the Ravens +17. And Detroit was an incredible -7 in close games with SB Champ Indy and the Titans both +5. The three unluckiest teams (Detroit, Cleveland and TampaBay) won a combined 11 games, while the three luckiest (Baltimore, Chicago and San Diego) won 40! In fact, there is a 76% correlation between the index and season wins. Partly that is because close wins obviously correlate 100% with wins; but the correlation between turnover margin + injuries with season wins is still 60%.
I strongly suggest you consider how lucky or unlucky a team was when looking at last year's record as you handicap this year's posted season win totals.
Reed Hogben M.D.
The Betting Doctor