The only constant...
Posted: Wed Feb 27, 2013 6:38 pm
In the context of my intermittent mini-crusade to have the empirical history of the NBA be taken seriously, I feel compelled to offer comment on a rather recent TrueHoop post: http://espn.go.com/blog/truehoop/post/_ ... -is-change. I really like me my Henry Abbott, but the factual presentation and related argument about historical matters in this post is really, really very not good.
Front and center is a graph that motivates the post (and conversation with Stu Jackson). We are shown a familiar rise in 3PA (though the data for early years are both incorrect and incorrectly labeled on the axis) and a perhaps less familiar decrease in FTA. Story: the only constant is change.
First red flag. There is, in fact, at least one eternal constant in the NBA, and that is: it is a very bad idea to foul three point shots. Accordingly, this is very uncommon. And this fact fully accounts for the apparent secular decline in FTAs over time. Were the plot instead to show, say, FTA/2PA over time, one would see something very interesting, namely a wave, with two peaks and two (and on the way to three) troughs. This too is change, of course, but of a completely different (and far more interesting) nature, and one that requires a different narrative (primarily responses to rules change regimes, both in player actions and enforcement). Perhaps a blog post for another day.
From here we turn to the interview with Stu Jackson, where very little is heard that is both nutritious and true. But more to the point, the degree to which falsehoods are related is perhaps a bit shocking.
Stu Jackson could be forgiven for not giving an honest answer as to why the three point shot has been so slow to be adopted. What is he going to say, that hewing to norms of respectability was, historically, more important than winning for NBA job security? So, we first get the nonsensical "there was going to be a bit of a lag time" argument. Note: it hasn't been "just" 20 years; it's been 34 years, not including the 9 years of ABA experience. And there was that funny bump up in 3PAs between 1995 and 1997. Explaining that would have been a nice follow up question.
But then we get the second reason, 3PAs were also supply constrained (again, never mind the amazing effect on supply of the experiment with the shorter line): "it took some time for teams to start making the personnel decisions that allow them to incorporate three point shooting". And then we get an example: stretch 4s are required to stretch the floor, get adequate spacing, blah, blah, blah.
Huh.
OK. Plausible. (Henry seems to nod in agreement.) But is it true? Well, basketball-reference says it isn't, if that means one should expect an increasing number of F-Cs over time shooting threes proficiently enough to be a threat (I picked 3fg% of 35). If anything, the correlation is negative. Is there another interpretation that I am missing that redeems his point?
Then the interview continues about the effect of rule changes on the supply of players able to "work their magic around the rim". This is then followed by another factual curiosity from the VP of Basketball Operations. Unprompted, the claim is made that "the small guard has come back into the game...certainly guys under 6 foot, playing the point guard position...".
Seems reasonable, but, again, is this true? Well, basketball-reference says no. Both for guards under 6' and 6'2" (I stopped checking there) their absolute numbers and numbers playing starter minutes hasn't increased since hand-checking rules went in effect. If anything, their participation has gone done over the longer term.
Well. So what? What's the point of fisking the VP? Perhaps none. Everyone, pretty much, prefers the rule changes allowing zone and eliminating hand-checking, etc. Still, it is a bit disconcerting when the person nominally in charge of instituting rule changes so as to modify the nature of the game gives the impression that he both "knows" the specific consequences to be different than they actually are and misunderstands the casual relationships driving fundamental changes in the way the game is played.
Maybe I'm just being a bit too cranky. Maybe the whole point of the post was simply to plug HoopIdea, using up some All Star Weekend footage in the process. But then again, maybe there's some value in having a clear understanding of the evolution of the game.
Carry on.
Front and center is a graph that motivates the post (and conversation with Stu Jackson). We are shown a familiar rise in 3PA (though the data for early years are both incorrect and incorrectly labeled on the axis) and a perhaps less familiar decrease in FTA. Story: the only constant is change.
First red flag. There is, in fact, at least one eternal constant in the NBA, and that is: it is a very bad idea to foul three point shots. Accordingly, this is very uncommon. And this fact fully accounts for the apparent secular decline in FTAs over time. Were the plot instead to show, say, FTA/2PA over time, one would see something very interesting, namely a wave, with two peaks and two (and on the way to three) troughs. This too is change, of course, but of a completely different (and far more interesting) nature, and one that requires a different narrative (primarily responses to rules change regimes, both in player actions and enforcement). Perhaps a blog post for another day.
From here we turn to the interview with Stu Jackson, where very little is heard that is both nutritious and true. But more to the point, the degree to which falsehoods are related is perhaps a bit shocking.
Stu Jackson could be forgiven for not giving an honest answer as to why the three point shot has been so slow to be adopted. What is he going to say, that hewing to norms of respectability was, historically, more important than winning for NBA job security? So, we first get the nonsensical "there was going to be a bit of a lag time" argument. Note: it hasn't been "just" 20 years; it's been 34 years, not including the 9 years of ABA experience. And there was that funny bump up in 3PAs between 1995 and 1997. Explaining that would have been a nice follow up question.
But then we get the second reason, 3PAs were also supply constrained (again, never mind the amazing effect on supply of the experiment with the shorter line): "it took some time for teams to start making the personnel decisions that allow them to incorporate three point shooting". And then we get an example: stretch 4s are required to stretch the floor, get adequate spacing, blah, blah, blah.
Huh.
OK. Plausible. (Henry seems to nod in agreement.) But is it true? Well, basketball-reference says it isn't, if that means one should expect an increasing number of F-Cs over time shooting threes proficiently enough to be a threat (I picked 3fg% of 35). If anything, the correlation is negative. Is there another interpretation that I am missing that redeems his point?
Then the interview continues about the effect of rule changes on the supply of players able to "work their magic around the rim". This is then followed by another factual curiosity from the VP of Basketball Operations. Unprompted, the claim is made that "the small guard has come back into the game...certainly guys under 6 foot, playing the point guard position...".
Seems reasonable, but, again, is this true? Well, basketball-reference says no. Both for guards under 6' and 6'2" (I stopped checking there) their absolute numbers and numbers playing starter minutes hasn't increased since hand-checking rules went in effect. If anything, their participation has gone done over the longer term.
Well. So what? What's the point of fisking the VP? Perhaps none. Everyone, pretty much, prefers the rule changes allowing zone and eliminating hand-checking, etc. Still, it is a bit disconcerting when the person nominally in charge of instituting rule changes so as to modify the nature of the game gives the impression that he both "knows" the specific consequences to be different than they actually are and misunderstands the casual relationships driving fundamental changes in the way the game is played.
Maybe I'm just being a bit too cranky. Maybe the whole point of the post was simply to plug HoopIdea, using up some All Star Weekend footage in the process. But then again, maybe there's some value in having a clear understanding of the evolution of the game.
Carry on.