Great Expectations

Finally, the men’s bracket at the Western and Southern Open tennis tournament stayed still long enough for me to model it. Here are the results:

This table is sorted by the player’s official world ranking, which is how the top 16 players in the bracket were initially seeded. While the ATP rank is obviously correlated with skill to some extent, it’s not the best available way to assess relative skill. For the purposes of the model, the primary indicator of skill is the odds offered on Betfair, a clearinghouse for sports wagering, on Friday night before the tourney started. ATP rank was the secondary sort, where the Betfair odds were equal, and for the qualifiers and lucky losers.

There are some biases in the Betfair odds. One is that there were no odds quoted for qualifiers and those who became lucky losers, so those folks all go to the bottom of the list, even though some of them would, no doubt, have been quoted at shorter odds if it had been known that they’d be in the main draw. There’s also a distinct bias in favor of Americans. John Isner has the eleventh best ATP ranking, but had the fourth shortest betting odds, presumably reflecting the assumption that he’d do particularly well in familiar surroundings in front of a supportive crowd.

Note that the simulation is for the bracket before any games had been played. Now, of course, the winnings of about half the field are known with certainty because they’ve already been eliminated – they earn $17,700 if they were eliminated in the first round, or $32,780 if eliminated in the second. The point here is not to predict anyone’s actual outcome, but rather to show how the peculiar practices of the ATP with regard to filling their brackets cause some odd anomalies.

Here’s a doozy. The seven qualifiers – Smith, Youzhny, Dolgopolov, Eubanks, Marterer Krueger, and Sousa – collectively can expect to earn $228,451. But the seven players they beat in the qualifying finals collectively expect $250,320! At it turned out, the qualifiers would have done better, on average, if they’d lost that last qualifying match, and taken their chances to be lucky losers.

ATP rank skill rank expected winnings
2 1 Nadal $406,330
7 5 Thiem $188,187
8 2 A. Zverev $299,402
11 3 Dimitrov $210,528
12 6 Tsonga $132,150
13 16 Goffin $45,745
14 9 Berdych $70,493
15 21 Carreno Busta $59,376
16 17 Bautista Agut $77,293
17 10 Sock $93,214
19 4 Isner $133,810
20 11 Querrey $89,295
21 12 Muller $65,476
23 43 Ramon-Vinolas $36,025
24 7 Kyrgios $81,424
25 29 Fognini $40,113
26 18 M. Zverev $62,326
28 13 Lopez $49,956
29 22 Gasquet $40,320
30 30 Khachanov $50,040
31 8 Del Potro $77,684
32 20 Anderson $48,741
33 33 Ferrer $46,834
34 14 Karlovic $52,000
35 23 Johnson $59,975
36 31 Schwartzman $49,237
38 36 Lorenzi $41,225
40 24 Verdasco $50,870
41 34 Paire $40,124
42 44 Mannarino $37,756
43 19 Edmund $62,351
44 32 R. Harrison $35,599
45 25 Troicki $35,698
46 37 Sugita $36,939
48 26 Medvedev $42,822
49 27 Vesely $35,080
51 45 Sousa $35,438
52 35 Hasse $43,339
55 38 Coric $48,818
56 15 Chung $45,213
58 46 Tipsarevic $66,079
61 28 Young $41,244
63 39 Basilashvili $48,026
66 40 Donaldson $42,145
71 47 Dolgopolov $30,743
84 41 Tiafoe $33,803
85 48 Fabbiano $64,448
98 49 Youzhny $33,813
122 50 Marterer $30,747
132 51 Koslov $32,045
174 42 Paul $33,135
180 52 Ramanathan $41,403
212 53 Smith $26,854
240 54 C. Harrison $66,150
244 55 Krueger $31,285
374 56 Eubanks $39,580

There’s more to be said about these results, but that will have to wait for tomorrow.

 

2 thoughts on “Great Expectations”

  1. Pingback: Who Won the Draw?

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