August 24, 2016
Now that the regular season is over, let’s take a look at how teams stack up in various statistical categories. With teams playing more games and giving us a larger sample size, some of the extremes noted in previous updates have shrunk.
There were some changes in net rating after the Olympic break. In the graph, the blue bars represent offensive rating and the red bars represent defensive rating, leaving the difference between the two as the net rating. Minnesota had already become the leading defense, but they also took over the offensive leading as Chicago also managed to leapfrog Los Angeles. While only three teams averaged more points per possession than they gave up at the break, the season finished with half of the teams holding a positive net rating.
While the top two teams clearly have strength in both categories, the next two teams have very different methods for winning games. Chicago’s offense is excellent and ranked second, but their defense struggles mightily at second worst. New York only has the second most potent offense, but they are a clear third place among defenses. The contrast set up interesting playoff matchups in the second round with the more offensively minded Phoenix visiting New York while defensively oriented Atlanta drew Chicago.
The x-axis in the graph represents offensive rebounding percentage while the y-axis represents defensive rebounding percentage. Six teams established themselves as top teams on the offensive glass, but there was a spread in how well they grabbed boards on the other end. New York, Minnesota, Chicago, and Connecticut were the top four teams on the defensive glass while also ranking between second and fifth on the offensive end. Atlanta was the best at grabbing its own misses, but was far more pedestrian at cleaning up after opponent’s misses. Dallas was not as proficient at offensive rebounding after the Olympic break and also saw no improvement on its league worst ranking at defensive rebounding. None of the teams that were weaker at offensive rebounding were particularly strong at defensive rebounding either as Indiana managed to float around the average in both categories.
How teams got their points began to even out as the season progressed, but there are still some interesting trends. The blue portion of each bar represents percentage of total points from two point field goals, the red portion of each bar is the percentage of points from three pointers, and the green portion is the percentage of points from free throws. Teams are listed in order of offensive rating.
The top two offenses get more of their points from inside the arc than any other team and are both in the bottom three of points from beyond the arc. Los Angeles, which was just behind them on the offensive efficiency ladder, had a more balanced mix between the types of field goals, but was one of the least reliant on points from the free throw line. Dallas continued to only get slightly above half of its points from inside the arc, finishing in the top three in percentages for the other two categories. Atlanta continues to have a clear style, getting the highest percentage of their points from the free throw line while getting the lowest percentage of their points from behind the arc.
Opponents Points Breakdown:
There are fewer clear trends when looking at how teams gave up their points. The blue portion of each bar represents percentage of total points given up from two point field goals, the red portion of each bar is the percentage of points given up from three pointers, and the green portion is the percentage of points given up from free throws. Teams are listed in order of defensive rating.
The top three defenses were in the top five in percentage of points given up that came from behind the arc, but Chicago, which ranked as the worst in the category, had one of the worst defensive overall while giving up the lowest percentage of points from inside the arc, an interesting contrast with their offense. Dallas on the other hand, had the lowest percentage of the points scored on them from beyond the arc, but that may be due to giving up the second highest percentage of points from inside the arc on their way to having the lowest defensive rating. Seattle had a similar defensive profile, but finished fourth, not giving up too many points from the free throw line.
Correlation with Offense:
How well do other statistical categories correlate with offensive efficiency? Let’s take a look at some metrics that would generally be associated with good offense and also some categories that might not be thought of as being related. For each category, the direction of the correlation from the final team statistics is mentioned and the R-squared value, which runs between 0 and 1, is included.
As it turns out, there is not too much that can be gleaned from the data. The only category that seems to have anything above a weak correlation is assist to turnover ratio. As would be expected, teams with higher assist to turnover ratios tended to have greater offensive efficiency. Turnover percentage moves in the same direction as a higher turnover percentage correlated with lower offensive efficiency. Somewhat surprisingly, neither free throw rate nor offensive rebounding showed much correlation even though it would seem like both should contribute to offense. Defensive rebounding actually had a stronger correlation although it could be explained by the conservation of energy from spending less time on defense. Defensive rating also correlated in the expected direction, although it was not particularly strongly as worse defenses tended to also have worse offenses.
All stats from wnba.com and include all regular season games.