Bell Sounds Off

The biggest upset in MLB in 14 years last night, as the Kansas City Royals defeated the New York Yankees who were a -410 favourite in US odds.

This equates to 1.2439 in decimal odds, so an implied losing probability of 19.6% coming to fruition isn't usually exactly earth shattering, but the nature of baseball means that this was only the tenth -400 or shorter selection since 2004.

RJ Bell, a name covered in this blog on a couple of occasions back in 2016 took to Twitter to make a highly dubious comparison with the NFL:

At -410, this was indeed the biggest favourite to lose in the MLB since 2004, although it should be noted that this loss was only 13 days after the Houston Astros lost as -400 favourites versus the Detroit Tigers. July can be a tricky month with the All-Star game disrupting routines as I've mentioned before.

But the attempted comparison with NFL favourites at -15 or more is a strange one. There really is no comparison. I replied:

The nature of the sport (MLB) means that it is very rare to find a team with a win probability greater than 0.8. With 2,430 regular season games per season, and not even including the post season, 15 bets out of 35,545 plus opportunities is less than 0.0004.  

NFL games where a team is favoured by 15 points or more? 48 from 'just' 4,005 games, i.e 0.012, or approximately 28 times as frequent. 

As for the -15 handicap being considered equivalent to -400 on the Money Line, I have the -8.5 handicap as closer. Teams at -15 win around 95% of the time, not around 80%.