Small Ball - Do lighter and/or shorter NBA teams have different winning percentages?

After watching the Pacers hang with the Heat through seven games on the strength of Roy Hibbert and David West pushing the smaller Miami defenders around – and having significant concerns about Nerlens Noel and his 206 lbs. coming to Cleveland with the number one pick – I want to look at the impact of weight on team performance.

I will weight the player weights by minutes played to put an average size on the lineups being rolled out by each team throughout the season and limit myself to the past five seasons so I don’t have to steal too much data from www.basketball-reference.com

Promisingly for Nerlens Noel’s prospects, the weight of the average lineup appears to have almost no correlation with winning percentage (0.05), ORtg (0.08) or DRtg (0.002). Statistics related to playing inside, as you would expect for a heavier team, show bulkier, more substantial correlations: turnover percentage (0.36), ORB% (0.25) and FT/FGA (0.23). The fatter huskier teams also failed to distinguish themselves in attendance with a negative correlation coming in at -0.10.

The distribution of teams is about as close to the textbook definition of random data as you can get. In fact, here is the distribution of random normal data recentered to the mean/standard deviation of the NBA data.

On the other easy-to-visualize metric of team physical appearance – height – there is a similar lack of relationship with the key metrics. Correlation with winning percentage (0.01), ORtg (0.11) and DRtg (0.09) is in the vicinity of perfectly unrelated – the mild improvement in offensive performance of taller teams is offset by an equally mild decrease in defensive performance (lower DRtg is better). Height has a hefty correlation with ORB% (0.28) similar to weight’s correlation with that metric, but the TOV% (0.11) and FT/FGA (0.12) correlations are much slimmer than those for weight.

In the current NBA Finals matchup between the Spurs and the Heat, the season-average lineups for the two teams have the Spurs outweighing the Heat 217.5 to 215.9 pounds (about 0.4 standard deviations) while San Antonio's height advantage is 78.76 with Miami averaging 78.43 inches (a difference of 0.75 standard deviations).

All in all this analysis doesn’t deliver the big insights I was hoping for, but does allow me to unload a small number of weight-related puns. For that I am grateful.
 

On the injury rates of running QBs: The future is now

The NFL, we are told at length, is on the brink of a new era of dual-threat quarterbacks. These new QBs will take advantage of their rushing ability to put the defense off-balance and change the way the game is played. Stop me if you have heard this before.

The dual-threat QB is hardly a new phenomenon. Quarterbacks were, of course, originally more like running backs in the early days of football. While my command of football history is far short of sufficient for this or any other analysis, such names as Fran Tarkenton, Randall Cunningham, Donovan McNabb, Michael Vick and Steve Young have demonstrated the power of a QB with the ability to run the ball.

That a dual-threat QB could offer an improvement over a traditional drop back passer should not be in serious dispute. Given two QBs of equal passing ability, the one of the two with greater rushing ability will almost certainly have better performance – in passing as well as in rushing. The statuesque, lumbering traditional QB will have far fewer scrambles for first down, more sacks (assuming equal ability and judgment to throw the ball away in a hopeless situation) and more marginal throws forced in.

The dual-threat QB will have a huge impact even before the snap. The defense will have to consider him a threat to run even on a play that looks like a certain pass, pulling one defender away from the passing game and opening up better opportunities for completion. Once the play begins, the dual-threat QB will have the benefit of an additional option should the receivers look covered. Rather than forcing a marginal throw, throwing the ball away or taking a sack, this QB can make something happen on his own. Again assuming equal judgment and passing ability, the dual-threat QB will trade some of the worst throws of his almost-doppelganger for some scrambles that are far less likely to be turnovers and far more likely to yield positive yardage.

Despite all this upside the dual-threat QB seems prone to injury concerns that will keep him out of reach. Redskins fans in particular may be having second thoughts about Robert Griffin III tallying 120 runs – tied for the league lead among quarterbacks.