The Toronto Raptors are in the middle of an impressive regular season. They have outscored opponents by 8 points per 100 possessions this season, the second best mark in the league behind only the Warriors, per basketball-reference. Regular season success is nothing new for the Raptors, as Toronto has posted a net rating of at least +3.5 in each regular season since 2013-14. This Raptors team has not only built upon the successful campaigns of the previous seasons, but also added new dimensions to their game. Their upgraded shot selection on offense has them currently ranked 7th in the NBA in 3-point attempt rate.
While the Raptor’s statistical profile is once again impressive, I can’t help but get the feeling that a lot of NBA fans are probably having right now: We’ve seen this story before. A strong regular season Raptors squad goes into the postseason and helplessly fizzles out. This feeling is backed up by the performances Toronto has put up in the playoffs since the 2014 season.
*TOR and Opp. Net Ratings are Toronto and the Opponent’s regular season point differentials per 100 possessions.
**Net Rtg. Result is the points per 100 possessions that the Raptors outscored the opponents by in the series (a negative value means the Raptors were outscored).
As can be seen from the table, Toronto has only managed to outscore its opponent in 2 of 7 playoff series despite posting the better regular season net rating 6 of 7 times. They were even outscored by Indiana in a 2016 series which the Raptors won in 7 games. The Raptors have clearly been handily defeated twice by the Cavaliers, but they also endured a 14.5 point net rating defeat to a lightly regarded Wizards team in 2015 and played two close series against teams that actually had negative regular season net ratings (Brooklyn in 2014 and Milwaukee in 2017). What is going on here?
As a statistically minded person, I recognize that 7 playoff series is not a large sample to draw conclusions from. Moreover, individual series can be complicated by injuries on one or both sides, such as the Kyle Lowry injury against Cleveland last season. Still 7 series is more evidence than simply 1 or 2, so I decided to run a statistical test to determine the strength of the evidence in favor of the hypothesis that the Raptors have performed worse in the playoffs than their regular season net ratings would predict.
To do this, I ran a linear regression to predict the net rating result of a playoff series (the point differential per 100 possessions) based on the regular season net ratings of both teams involved in the series. I used all playoff series in the last 20 years to make this linear model. A plot of the regression line along with where the Raptor’s series fit in this analysis is below:
* Regular Season Net Rating Dif. and Series Net Rating Dif. are from the perspective of the HIGHER SEED in each series. For example, the fact that the dot marked WAS 2015 is at -14.5 on the vertical axis means the 2015 Raptors (the higher seed) were outscored by 14.5 points per 100 poss.
** The solid black line is the predicted result from the linear regression. Thus the Raptors underperformed their expected performance in each series in the plot.
We would expect, based on the regular season net ratings of Toronto and their opponents, that the sum of net rating results from the seven playoff series would be about +21.6 in favor of the Raptors. The actual sum of playoff results, from the Raptors perspective, is -47.6. This number is obtained by simply adding the net rating results in the final column of the table above.
In other words, the Raptors have performed on average about 9.9 points per 100 possessions worse in their playoff series than we would expect based on the regular season strengths of the two teams competing. If we assume different playoff series are independent, we find that there is about a 1 in 10,000 chance that Toronto would perform this poorly through chance alone.
Of course, the small sample size makes the evidence a little less convincing. Moreover, two of the series in the sample were against a Cleveland team that has notoriously been a better post-season squad than a regular season one. If we remove the two Cleveland series, the Raptors have still underperformed by an average of 8.1 points per 100 possessions per series. Toronto’s odds through chance alone of underperforming their regular season net rating in the other five series is about 5 in 1,000. In other words, the Cavs are not the only source of the Raptor’s problems.
The irony of this type of analysis is that the Raptor’s stellar regular seasons have made the evidence stronger that they are a playoff underachiever. If they were a weaker regular season team, their drop-off in performance in the postseason would be less dramatic.
Once again, I caution that 7 playoff series is more data than 1 or 2 but still not a large sample to draw conclusions from. Also, this edition of the Raptors is at least 2 points per 100 possessions stronger than any of the other teams studied. That is not a trivial difference.
We will have to wait until April to see if this is the year that Toronto finally flips the script or if the 2017-18 team will provide yet another data point in favor of the hypothesis that they are a poor playoff team.
-The photo at the beginning of the post of Kyle Lowry and John Wall was taken by Keith Allison on November 2, 2016 as part of the Raptors at Wizards 11/2/16 album. The photo is on the flickr and can be found by clicking here.
-All data is courtesy of basketball-reference, a fantastic resource.