Oct 14, 2013; Dallas, TX, USA; Orlando Magic power forward Solomon Jones (22) guards Dallas Mavericks small forward Renaldo Balkman (13) during the game at the American Airlines Center. The Magic defeated the Mavericks 102-94. Mandatory Credit: Jerome Miron-USA TODAY Sports
The headline of this article is only partially, marginally, fractionally true. Chances are your perception of Balkman as a professional basketball player is in the vicinity of dead-on-balls accurate—high energy, reasonably effective defender, helpful on the glass, extremely limited on offense, probably shouldn’t have been drafted 20th ahead of Rajon Rondo, Kyle Lowry and Paul Millsap. Almost all of that is true, and the fact that he’s playing for the Texas Legends of the D-League and hasn’t been seen in an NBA game since 2011-12 speaks loudly to his overall value as a potential NBA player.
However, there is the possibility of arguing, mildly, with the assessment of Balkman as a “reasonably effective defender.”
Yesterday, our own Layne Vashro released a public version of a tool he’s quietly been working on for some time. The tool is a series of player ratings based on how each player affects his team’s performance in The Four Factors — eFG%, TO%, FTR and REB%[1. This builds off of work from Got Buckets and Evan Zamir.]. If you’re curious about the methodology, there is a lengthy description at the bottom of the tool. The short version is that using a regularized adjusted plus-minus (RAPM) framework, Vashro was able to control for teammates and quality of opposition to put each player into a percentile rank by how large their effect is in each category.
There are several different filtering tools, but they let us see things like Steve Nash had a really positive effect on his team’s eFG%.
We’re looking at a smaller sample, Balkman never played more than 1,100 minutes across these three seasons. Yet, in both of his New York seasons here he ranked better than the 94th percentile in his effect on his team’s defensive eFG%, and better than the 93rd percentile in his effect on his team’s defensive TO%. In both of those seasons he ranked better than the 95th percentile in overall marginal defensive impact. It’s also worth noting that the percentile ranks use all players and all seasons in the sample, not just the player season. So Balkman is being compared to all player seasons from 2001 to 2015 with at least 750 minutes played, not just the players from each individual season.
These ratings come with all the caveats that go with plus-minus analysis. They can be noisy, although that noise is much less significant than it was with early plus-minus models. They also can obscure context. For example, we can see here that Balkman helped his team’s field goal defense dramatically, but we can’t see why or how. However, splitting the ratings out like this by the Four Factors can offer a slightly more detailed picture of a player’s contribution than a simple RAPM or RPM rating, split into offensive and defensive halves.
And, most importantly, these ratings offer statistical evidence that Isiah Thomas knew what he was doing all along as Knicks GM. He’ll be expecting your apology.