Friday 6 October 2023

Baseball, Interrupted

I haven't written too much about baseball this season, since the significant rule changes implemented this season rendered previous (pre-COVID) data pretty much worthless and I decided to wait-and-see for the most part.

The new rules seem to have been effective, with MLB reporting a 9.6% increase in attendances this season, although the first post-season game had the smallest attendance in over 100 years yesterday, and the average duration of a nine inning game down to 160 minutes, the shortest in 40 years.

As expected, the new rules meant more runs scored (+7% per game in 2023 from 2022), and more stolen bases (+40%) but as these were expected, there was no blanket edge on the totals which were split almost exactly 50/50 : 1169 to 1165 with 85 pushes. 

With the regular season now over, I took a look at how some of the previously profitable systems would have fared with the new rules. 

Starting with the 'hot favourites' system, and for the six seasons before COVID, the ROI on the Money Line was 7.3% (310.78 units) while the Run Line was just behind at 7.1% (156.07u) with the difference due to the higher overround in the latter's prices. 

Unfortunately, for many reasons, along came the pandemic, and everything went to pot. Significant changes were made to the rules, and the the much shorter and delayed COVID season of 2020 would have seen the same system as above produce losses of 4.8% (-16.25u) and 11.7% (21.35u).

The National League reverted to not using the Designated Hitter (DH) rule in 2021 and some normality was restored with the relative numbers being 8.1% (85.52u) and 7.9% (44.65u) but unfortunately for no other reason than to mess up my systems, the DH rule was adopted universally leading to a 2022 season where the numbers were -3.7% (-52.66u) and -4.9% (-35.55u). 

The wait-and-see approach for 2023 meant I was able to avoid losses of 6.3% (-72.28u) and 5.3% (-31.47u). Sometimes the best betting decision is not to bet. 

Back in July, I observed that:
The markets do seem to be overrating home AL favourites this season when playing NL teams, so there might be an edge opposing these
This strategy would have resulted in a small profit, but using Killer Sports these days is somewhat misleading with the change in overround that I mentioned earlier in the season. Even so, had you followed this strategy from the start of the season, the ROI would have been 3% but in reality higher.

COVID also killed off the T-Bone System which long-time readers may recall was successful for many years. From 2011 to 1019, the system had an ROI of 7% from 1090 bets, but since COVID has reversed to one of -7.3% from 685 bets. Opposing these selections would have given you an ROI of 5%, again a number that could easily be improved upon.

One system, and a good time to mention it with the regular season over, which does seem to be relatively untouched is the UMPO system, which again has been around for a long time, although with a small number of selections each season, it's highly sensitive to variance.

It would normally be in contention for a place in the Sacred Manuscript but with the turmoil around the baseball markets, for now it's on the watch-and see list.

Here are the latest numbers for the basic strategy, but touching back on the overround issue, using Bet365's prices for this season, the profit would be 12% greater than the 'official' returns.

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