2005-06 NBA Playoff Review

  • SportsInsights.com Article — NBA Playoffs: Betting Against the Public & Other Biases

The NBA Playoffs are upon us and SportsInsights took a quick peek at our database to see if any interesting results could be uncovered.  We DID discover some interesting biases, which our members will be happy to learn about.  The information on this site is for entertainment and educational purposes only. Use of this information in violation of any federal, state, or local laws is prohibited.

NBA Playoffs – Data (2003-2006 Seasons)

SportsInsights’ database for the NBA Playoffs include playoff games over the past three seasons (2003-2006).  Our study includes over 250 games.  This is not a huge number of games — but for the most part, the results continue to back some of the same methods and philosophies that SportsInsights encourages.  In this article, we focus on Betting Against the Public and Home field advantage.

Bias for Home Teams

Over the past three seasons, there is a bias for home teams to cover the point spread.  Home teams have covered at a rate of almost 54%.  This is not quite enough to eke out a healthy profit — but is a bias that should be noted (and we’ll use this to our advantage below!).  This “Home Team Bias in big games” jives with other results we have seen.  Again, please note that for the NBA playoffs, this bias is based on relatively few data points.

Betting Against the Public and Home Bias

During the NBA Playoffs, the public betting percentages do not get to the same extremes (85%/15% and 80%/20%) we see during the regular season.   Perhaps due to better teams in the playoffs, the betting percentages don’t often extend beyond the 65%/35% range.  Thus, SportsInsights members might not want to wait for the 25% or so range that the entire dataset — and regular season — suggests.

Combining the Bias for Home teams during the Playoffs with Betting Against the Public, we find that betting on Home Teams with less than about 40% of the Public on the Home Team — has resulted in a winning percentage in excess 60% over the past three playoff seasons.

We do not show a table because there are relatively few data points (and in fact, not many games where the public is lower than 30% on either side).  Again, just a gentle reminder that these results are not based on a statistically significant number of games.  However, the fact that the results are similar to other studies we have performed (and other research within the sports industry) gives us comfort that the results are robust.

Check in with SportsInsights regularly for sports information updates — and timely research in the sports betting arena.  SportsInsights.com performs objective data analysis to help our members profit in sports investing.

We do not guarantee that the trends and biases we’ve found will continue to exist. It is impossible to predict the future. Any serious academic research in the field of “market efficiencies” recognizes that inefficiencies may disappear over time. Once inefficiencies are discovered, it is only a matter of time before the market corrects itself. We do not guarantee our data is error-free. However, we’ve tried our best to make sure every score and percentage is correct.