"Contrarian Bridgejumping" Revisited

To refresh everyone's memory, the "C/B Jumping" methodology involves looking at how a team has done against the line set on its games. Many people look at a team's "net points" on the year (points for minus points against), but few people actually track how a team has done on average against the spread of its games. For instance a team that wins by ten points when they were favored by seven would have a +10 for "net points" but only a +3 for their performance against the line in that event.

The C/B Jumping theory said to play a team in a matchup whose "net against the line" was more than SIX points WORSE than its opponent. E.G. Team A is +2 against the line on average, Team B is -5, so you would play Team B since it is 7 points worse. (For the full text of the original article read "Contrarian Bridgejumping").

We'll take a look at this approach using a database that includes all the games played from week 5 on from 1983-2000:

ANALYSIS: The original theory only involved looking at the big difference (6+) matchups, and in those two columns above (the 6-7.9 range and 8+ range) the total adds up to a 589 - 479 record, which is 55.1% overall...not bad, but not the heights of the 1992-1996 period (there are admittedly some likely discrepancies between the lines we are using now and the lines in the database used for the prior assessment).

What is particularly interesting is that favorites have been astonishly good plays under these circumstances -- 142-94 overall (60%) and a scintillating 50-22 (69%) in cases where the favorite is favored by 5+ points. So it would seem the theory has considerable merit over the lengthy time period of 18 years.

The next concern is "what have you done for me lately?"

ANALYSIS: An 81-56 record in the key 6+ difference games, good for 59% against the spread...uh, yeah I'll take that! On the other hand, favorites with the C/B call have only been 14-17 against the line, so it's a dog driven method of late, turning the tables somewhat on previous patterns.

UPDATE: in 2004 the CSM was 25-24 (51%) and in 2005 just 28-32 (47%) so there are signs that the method has been weakening of late.

Editor's Note: the original 'Contrarian Bridgejumping' moniker has been replaced with the more descriptive, if not as colorful, 'Cumulative Spread Margin' or CSM for short.