Futures Win Inflation
TL;DR: In the MLB Futures Market Win Total O/Us, the estimated hold you’re paying on the over will likely approach 8 percent while the estimated hold on the under can be close to zero. With a little line shopping between books, you can probably find some unders with +EV without too much effort.
A new MLB season is starting and you’re excited to bet the over/under on win totals for your favorite team, the New York Yankees. After all, they picked up Cy Young winner Gerrit Cole, their offense is as potent as ever, and that team that plays in Massachusetts just threw in the towel by trading their best player.
You check out your favorite sportsbook and they are offering Yankees win totals at 101.5 -110/-110. You figure to yourself that since the futures markets typically have a very high hold, paying an effective hold of 4.5% (on -110 both ways) is not a bad way to bet your favorite team to have a good season.
Unfortunately, sportsbooks are well aware of our homer biases and shade the win totals upwards, something we’ll call win inflation.
In the MLB there are a total of 30 teams, each of which play 162 games. Occasionally, a team will play a 163rd game to settle a tiebreak, but we can generally expect a total of 2,430 regular season games to be played (30 x 162 x ½). Therefore, if 2,430 games are played, there are a total of 2,430 wins available for all 30 teams to share.
2020 Season - Win Inflation Across Books
We reviewed the season win totals markets of four U.S. sportsbooks. They all have various levels of win inflation, averaging 7 excess wins and ranging from one win to 13 wins.