In the column he describes it in, TMQ claimed Isaacson-Tarbell finished the 2007 season 183-84, which is a pretty impressive 68.5% accuracy. However, in my analysis, I was only able to account for 176 correct picks (65.9%). I have triple-checked my results, so I'm going to blog them.
Here's a graph of how the Isaacson-Tarbell Predictor performs on historical data, from 1960 to 2007 (along with the same "Home Team" data as posted below).
Note that ITP seems to have its best years in the 60's and early 70's; about the same time the "Home Team" strategy gives its worst results. Then, during the late 70's, they close together, giving what looks to be much more correlated results.
ITP looks to be an interesting algorithm, but not quite the home-run TMQ makes it out to be (you can see why he didn't mention its performance on the 2006 season).
A few notes on methodology
- There are a number of tie games in the historical data, particularly before the advent of the overtime period for regular season games in 1974. Tie games are counted as a "push" for pick algorithms. As with the NFL, for the purposes of computing a winning percentage, push results are counted as half wins, half losses.
- TMQ's description of Isaacson-Tarbell reads
Best Record Wins; If Records Equal, Home Team Wins.
Instead of "best record", I used the easier-to-deal-with "best winning percentage". The only time this will matter is when two undefeated (or two winless) teams match up, and one has had their bye, and the other hasn't. Coincidentally, this situation came up in the 2007 season, when the 8-0 Patriots met the 7-0 Colts. They both have the same winning percentage (100%), but the Patriots have the better record (one more win).
