andrew_gelman_stats andrew_gelman_stats-2013 andrew_gelman_stats-2013-1804 knowledge-graph by maker-knowledge-mining
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Introduction: Dave Berri writes : A recent study published in the Social Science Quarterly suggests that these moves may not lead to the happiness the fans envision (HT: the Sports Economist). E. Scott Adler, Michael J. Berry, and David Doherty looked at coaching changes from 1997 to 2010. What they found should give pause to people who demanded a coaching change (or still hope for one). Here is how these authors summarize their findings: . . . we use matching techniques to compare the performance of football programs that replaced their head coach to those where the coach was retained. The analysis has two major innovations over existing literature. First, we consider how entry conditions moderate the effects of coaching replacements. Second, we examine team performance for several years following the replacement to assess its effects. We find that for particularly poorly performing teams, coach replacements have little effect on team performance as measured against comparable teams that
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1 we use matching techniques to compare the performance of football programs that replaced their head coach to those where the coach was retained. [sent-9, score-1.07]
2 First, we consider how entry conditions moderate the effects of coaching replacements. [sent-11, score-0.249]
3 We find that for particularly poorly performing teams, coach replacements have little effect on team performance as measured against comparable teams that did not replace their coach. [sent-13, score-0.973]
4 However, for teams with middling records—that is, teams where entry conditions for a new coach appear to be more favorable—replacing the head coach appears to result in worse performance over subsequent years than comparable teams who retained their coach. [sent-14, score-2.176]
5 Berri points to other studies from hockey, soccer, and basketball that come to similar conclusions: replacing a head coach does not, on average, lead to improvement. [sent-15, score-0.696]
6 He concludes: What these studies did is look at teams or players with different coaches and failed to find much of a difference. [sent-16, score-0.808]
7 That suggests that coaches in sports are not very different from each other. [sent-17, score-0.588]
8 It may be true (and more than likely very true) that you are better off with a professional coach than with a random person grabbed from the stands (or no one at all). [sent-18, score-0.611]
9 But it doesn’t appear that the choice of professional coach matters much. [sent-19, score-0.663]
10 Berri continues: And that means, if it costs a small fortune to fire your coach – and often it does – then a team is probably better off just keeping who they have on the sideline. [sent-20, score-0.742]
11 I have not read the linked studies but, from Berri’s description, they found that a replacement coach is no better, on average, than the coach that came before. [sent-26, score-1.022]
12 But how do you get from there to “it doesn’t appear that the choice of professional coach matters much”? [sent-27, score-0.663]
13 Nearly all coaches change jobs at some point, good coaches as well as bad coaches. [sent-28, score-0.92]
14 Argument 2 is associated with “we can do better” claims such as why we should fire 80% of public-schools teachers or Moneyball-style stories about how some clever entrepreneur has made a zillion dollars by exploiting some inefficiency in the market. [sent-41, score-0.285]
15 Berri’s example seems more like a pure case of argument 2: sports teams are spending millions of dollars on top coaches, and that’s a waste of money because professional coaches are essentially all the same. [sent-43, score-1.274]
16 With some effort you can make an “argument 1″ story here—the idea being that teams fire coaches because it makes the fans happy—but I don’t buy it. [sent-44, score-1.06]
17 There’s a lot better ways of spending millions of dollars to get all these things, than to blow it on coaches with no ability. [sent-46, score-0.681]
18 When argument 1 is uncorked, there is a tendency to treat the identified behavior as rational and normative, while with argument 2 there is typically an assumption that the newly discovered strategy is simply better. [sent-50, score-0.549]
19 To return to sports, I also wanted to bring up one of my pet ideas on why coaches get fired when they do: Dan [Goldstein] has another question that I think I have the answer to. [sent-53, score-0.435]
20 He writes that he “has always wondered why teams are so eager to fire their coaches after they lose a few big games. [sent-54, score-0.867]
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