Loading ...
Sorry, an error occurred while loading the content.

Re: [APBR_analysis] Re: Yao's Conditioning?

Expand Messages
  • igor eduardo küpfer
    ... From: John Hollinger To: Sent: Friday, February 06, 2004 4:12 PM Subject: [APBR_analysis] Re: Yao s
    Message 1 of 15 , Feb 6, 2004
    • 0 Attachment
      ----- Original Message -----
      From: "John Hollinger" <alleyoop2@...>
      To: <APBR_analysis@yahoogroups.com>
      Sent: Friday, February 06, 2004 4:12 PM
      Subject: [APBR_analysis] Re: Yao's Conditioning?


      > I know for a fact there have been games where he's gone with Taylor
      > the entire fourth quarter.
      >
      > One interesting thing with a study like this is the chicken vs. egg
      > question -- if we show he plays just as well with more minutes, does
      > that mean that it's a genuine fact, or does it mean that Van Gundy
      > doesn't play him a lot of minutes if he sees that Yao is playing like
      > crap?
      >

      I believe Van Gundy has been quoted as saying that he was limiting Yao's
      minutes for physical reasons. That is, he wants to limit Yao's exposure to
      potential injury. I don't really think that Yao's conditioning is in
      question, considering how many minutes he played last season between his NBA
      games and his off-season commitment to the national team.

      I began a study of this a couple of months ago, but didn't get far. Here's
      what I have:

      | YAO'S MINUTES | ROCKET's LEAD
      GAME | 1 2 3 4 OT | 1 2 3 4 OT
      -----|---------------------------------------------------
      1 | 9 5 3 3 | 2 6 12 17
      2 | 8 12 8 8 | -9 -1 5 -8
      3 | 8 10 11 0 | -7 -20 -29 -32
      4 | 9 10 9 8 | 1 -7 -5 11
      5 | 10 7 12 5 | 3 6 6 10
      6 | 12 3 7 10 | 0 7 9 20
      7 | 12 5 9 5 | -2 -6 -10 -11
      8 | 9 6 12 9 | 3 -6 -1 5
      9 | 8 10 9 12 10 | -8 -3 2 0 -4
      10 | 7 12 7 12 | 3 10 10 8
      11 | 7 7 9 12 | 3 4 -1 2
      12 | 8 10 9 10 | 11 -3 -7 -7
      13 | 10 7 10 4 | 4 14 7 15

      AVG 9.0 8.0 8.8 7.5 0.3 0.1 -0.2 2.3

      The numbers in the Yao's Minutes columns represent the number of minutes he
      played in each quarter. The Rockets Lead numbers are their lead at the end
      of each quarter (a negative number would be a Rockets deficit).

      There's not much to look at there, but you can see that in games where the
      score difference is 5 or less points, Yao plays about 10 minutes in the 4th.
      When the lead is more than 5, he plays 6 minutes in the 4th.

      ed
    • igor eduardo küpfer
      ... NBA ... he ... 4th. ... Er, here I am referring to the score difference at the end of 3 quarters, which I took to be indicative of the closeness of the
      Message 2 of 15 , Feb 6, 2004
      • 0 Attachment
        > ----- Original Message -----
        > From: "John Hollinger" <alleyoop2@...>
        > To: <APBR_analysis@yahoogroups.com>
        > Sent: Friday, February 06, 2004 4:12 PM
        > Subject: [APBR_analysis] Re: Yao's Conditioning?
        >
        >
        > > I know for a fact there have been games where he's gone with Taylor
        > > the entire fourth quarter.
        > >
        > > One interesting thing with a study like this is the chicken vs. egg
        > > question -- if we show he plays just as well with more minutes, does
        > > that mean that it's a genuine fact, or does it mean that Van Gundy
        > > doesn't play him a lot of minutes if he sees that Yao is playing like
        > > crap?
        > >
        >
        > I believe Van Gundy has been quoted as saying that he was limiting Yao's
        > minutes for physical reasons. That is, he wants to limit Yao's exposure to
        > potential injury. I don't really think that Yao's conditioning is in
        > question, considering how many minutes he played last season between his
        NBA
        > games and his off-season commitment to the national team.
        >
        > I began a study of this a couple of months ago, but didn't get far. Here's
        > what I have:
        >
        > | YAO'S MINUTES | ROCKET's LEAD
        > GAME | 1 2 3 4 OT | 1 2 3 4 OT
        > -----|---------------------------------------------------
        > 1 | 9 5 3 3 | 2 6 12 17
        > 2 | 8 12 8 8 | -9 -1 5 -8
        > 3 | 8 10 11 0 | -7 -20 -29 -32
        > 4 | 9 10 9 8 | 1 -7 -5 11
        > 5 | 10 7 12 5 | 3 6 6 10
        > 6 | 12 3 7 10 | 0 7 9 20
        > 7 | 12 5 9 5 | -2 -6 -10 -11
        > 8 | 9 6 12 9 | 3 -6 -1 5
        > 9 | 8 10 9 12 10 | -8 -3 2 0 -4
        > 10 | 7 12 7 12 | 3 10 10 8
        > 11 | 7 7 9 12 | 3 4 -1 2
        > 12 | 8 10 9 10 | 11 -3 -7 -7
        > 13 | 10 7 10 4 | 4 14 7 15
        >
        > AVG 9.0 8.0 8.8 7.5 0.3 0.1 -0.2 2.3
        >
        > The numbers in the Yao's Minutes columns represent the number of minutes
        he
        > played in each quarter. The Rockets Lead numbers are their lead at the end
        > of each quarter (a negative number would be a Rockets deficit).
        >
        > There's not much to look at there, but you can see that in games where the
        > score difference is 5 or less points, Yao plays about 10 minutes in the
        4th.
        > When the lead is more than 5, he plays 6 minutes in the 4th.
        >

        Er, here I am referring to the score difference at the end of 3 quarters,
        which I took to be indicative of the closeness of the game.

        ed
      • McKibbin, Stuart
        ... From: edkupfer@rogers.com Sent: Friday, February 06, 2004 1:35 PM To: APBR_analysis@yahoogroups.com; edkupfer@rogers.com Subject: Re: [APBR_analysis] Re:
        Message 3 of 15 , Feb 6, 2004
        • 0 Attachment
          -----Original Message-----
          From: edkupfer@...
          Sent: Friday, February 06, 2004 1:35 PM
          To: APBR_analysis@yahoogroups.com; edkupfer@...
          Subject: Re: [APBR_analysis] Re: Yao's Conditioning?
          I believe Van Gundy has been quoted as saying that he was limiting Yao's
          minutes for physical reasons. That is, he wants to limit Yao's exposure to
          potential injury. I don't really think that Yao's conditioning is in
          question, considering how many minutes he played last season between his NBA
          games and his off-season commitment to the national team.

          ed

          Well, I question his conditioning because I've seen games where the guy can
          barely make it up the floor. Especially faster paced games. He's slow to
          begin with and being tired makes him run about as fast as the Great Wall.
          Obviously, if Yao doesn't get back quickly the defense is weaker, so Van
          Gundy is forced to play him fewer minutes. Anyway, that's what I've seen
          with my own two eyeballs, but Ed's and Kevin's tracking of his minutes and
          production directly contradict me.
          Stuart
        • Michael Tamada
          There s strong support for a conventional story in those stats: close game at end of 3rd quarter == big 4th quarter minutes for Yao blowout game at end of
          Message 4 of 15 , Feb 6, 2004
          • 0 Attachment
            There's strong support for a conventional story in those stats:

            close game at end of 3rd quarter ==> big 4th quarter minutes for Yao
            blowout game at end of 3rd quarter ==> small 4th quarter minutes for Yao

            I took the absolute value of the 3rd quarter lead/deficit, and regressed Yao's 4th quarter minutes against that. Even with only 13 observations, the regression statistics support the conventional hypothesis (indeed, as Ed points out, simply eyeballing the numbers, this jumps out at you).

            The regression equation is

            4th qtr mins = 10.55 - .38*abs(lead)

            i.e. for every point by which Houston's lead or deficit grows, Yao's minutes diminish by .38 minutes. With a 28 point lead or deficit, we'd expect Yao to play 0 minutes (and lo and behold, in Game 3 Houston had a 29 point deficit and Yao sat).

            The t-statistic on the estimated coefficient of -.38 is -3.31, with a significance level of p = 0.7%, i.e. significant at better than the 1% level. Pretty good for a sample size of 13. The adjusted r-squared from the regression is .45.


            This regression benefits from what might be aguably a statistical outlier, that 29-point Game 3 blowout. If we leave that out of the regression, the coefficient estimate stays at around the same value, -.43, but the adjusted r-squared falls to .16 and the t-statistic is -1.77, significant at only the p = 10.7% level.

            So Game 3 probably makes these results look overly conclusive. On the other hand, it is almost certainly too drastic to literally throw out Game 3, a baby-with-the-bathwater move. Game 3 does provide support for the notion that big leads cause small minutes for Yao, so to totally ignore Game 3 is not a wise course.

            The regression might be further strengthened by correcting for censoring; it's physically impossible for Yao to play more than 12 minutes in the 4th quarter, and the data around the regression line thus hit a ceiling and flatten out at 12 minutes, making the estimated regression line probably flatter than it should be. And thus our estimates will be a little too low and seemingly lacking in significance.


            Of course, none of this explains the original question, about why Yao's total minutes are so low. Many other superstars probably get similar 4th quarter treatment (sit during a blowout, play during a close game); why do their minutes per game exceed Yao's by so much?


            --MKT


            -----Original Message-----
            From: igor eduardo küpfer [mailto:edkupfer@...]
            Sent: Friday, February 06, 2004 1:35 PM

            I began a study of this a couple of months ago, but didn't get far. Here's
            what I have:

            | YAO'S MINUTES | ROCKET's LEAD
            GAME | 1 2 3 4 OT | 1 2 3 4 OT
            -----|---------------------------------------------------
            1 | 9 5 3 3 | 2 6 12 17
            2 | 8 12 8 8 | -9 -1 5 -8
            3 | 8 10 11 0 | -7 -20 -29 -32
            4 | 9 10 9 8 | 1 -7 -5 11
            5 | 10 7 12 5 | 3 6 6 10
            6 | 12 3 7 10 | 0 7 9 20
            7 | 12 5 9 5 | -2 -6 -10 -11
            8 | 9 6 12 9 | 3 -6 -1 5
            9 | 8 10 9 12 10 | -8 -3 2 0 -4
            10 | 7 12 7 12 | 3 10 10 8
            11 | 7 7 9 12 | 3 4 -1 2
            12 | 8 10 9 10 | 11 -3 -7 -7
            13 | 10 7 10 4 | 4 14 7 15

            AVG 9.0 8.0 8.8 7.5 0.3 0.1 -0.2 2.3

            The numbers in the Yao's Minutes columns represent the number of minutes he
            played in each quarter. The Rockets Lead numbers are their lead at the end
            of each quarter (a negative number would be a Rockets deficit).

            There's not much to look at there, but you can see that in games where the
            score difference is 5 or less points, Yao plays about 10 minutes in the 4th.
            When the lead is more than 5, he plays 6 minutes in the 4th.

            ed




            Yahoo! Groups Links
          Your message has been successfully submitted and would be delivered to recipients shortly.