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

5113Re: possessions

Expand Messages
  • schtevie2003
    Oct 4, 2004
    • 0 Attachment
      --- In APBR_analysis@yahoogroups.com, igor eduardo küpfer <edkupfer@r...> wrote:
      > schtevie2003 wrote:
      > > --- In APBR_analysis@yahoogroups.com, igor eduardo küpfer
      > > <edkupfer@r...> wrote:
      > >>
      > >> Okay, how about this: team pace as the distribution of shot clock
      > >> time it
      > >
      > >> takes to get off the first attempt of the possession. If we ignore
      > >> possessions in which no attempt took place, and if we count shooting
      > >> fouls as attempts, the distribution of shot clock times for the
      > >> 03-04 Net's looks like this:
      > >>
      > >> Time RelFreq CumFreq
      > >>> 03 2.7% 2.7%
      > >>> 06 1.7% 4.5%
      > >>> 09 7.2% 11.7%
      > >>> 12 12.2% 23.9%
      > >>> 15 23.3% 47.2%
      > >>> 18 26.0% 73.2%
      > >>> 21 16.2% 89.4%
      > >>> 24 10.6% 100.0%
      > >>
      > >> That doesn't tell us too much, so let's compare them to other teams.
      > >> First, the 03-04 Raptors, which, to my eyes, were the slowest team
      > >> in the history of the NBA. The rightmost column is a random sample
      > >> of 44 NBA games.
      > >>
      > >>
      > >> NJ TRN X
      > >>> 03 2.7% 2.1% 1.9%
      > >>> 06 4.5% 3.6% 3.6%
      > >>> 09 11.7% 10.8% 11.8%
      > >>> 12 23.9% 22.5% 26.3%
      > >>> 15 47.2% 44.7% 50.0%
      > >>> 18 73.2% 70.6% 73.9%
      > >>> 21 89.4% 87.9% 89.7%
      > >>> 24 100.0% 100.0% 100.0%
      > >>
      > >> The Nets don't look that much different than average by this measure
      > >> of pace, which is consistent with other measures.
      > >>
      > >> ed
      > >
      > > A couple of impressions from the data given.
      > >
      > > I think the Nets do look different from average.
      >
      > They are. I should've said so. A chi-square test on the raw frequencies
      > shows a significant difference between the Nets and the NBA sample.
      > Statistical significance may not equate to practical significance though --
      > I see you address that below.
      >
      > > First (and let's stipulate that the NBA numbers are representative)
      >
      > This deserves examination, just to make sure. I analysed a second sample of
      > 45 games, and performed a X^2 test. The samples were not significantly
      > different .
      >
      > Here's my problem: parsing these numbers out of PbP logs is extremely time
      > consuming for me. I use Excel to do it -- not the best way. So while I'd
      > love to mine everything I can out of the logs, I'm limited to what my time
      > and basic programming skills have to offer.
      >
      > > they get 0.8% more fast breaks (shots within 3 seconds) than the average
      > > team. This is about one per game. And let's suppose (reasonably, I
      > think)
      > > that these shots earn 0.5 points more on average than all others.
      >
      > Here are the average number of points per possession when the first shot
      > attempt was taken in X seconds.
      >
      > Time of points/
      > 1stAtt poss
      >
      > :00-:03 1.43
      > :03-:06 1.46
      > :06-:09 1.26
      > :09-:12 1.18
      > :12-:15 1.19
      > :15-:18 1.16
      > :18-:21 1.12
      > :21-:24 0.99
      >
      > For some reason, the quick attempt is not quite as effective as the 3-6
      > second attempt (the difference is not significant). Go figure. In any case,
      > I think we're not just talking about fast breaking teams, but fast pace
      > teams -- to me, that is a team that pushes the ball upcourt quickly, not
      > necessarily taking an attempt quickly. I'm willing to include 3-6 second
      > attempts in a "fast pace" definition.
      >
      > I'm afraid I can't finish this post right now. If you want to reassess your
      > suppositions in light of the numbers above, I'd like to see it. I'm also
      > willing to do a bit more work on this over the weekend if you have anything
      > specific you'd like me to check.
      >
      > --ed

      Thanks for the data. I am not sure if the latest "points per possession" data are just for
      the Nets or reflect the supposed NBA average. As for a reassessment of suppositions, I
      feel comfortable with my general initial assessment - especially if one allows that a real
      fast break could take more than 3 seconds and still be considered such. Just eye-balling
      the data, one expects about 0.3 more points per possession when one shoots within the
      first 6 seconds and than when one shoots afterwards. My guess of 0.5 still seems about
      right to me when one includes turnovers in the mix - as the expectation of these should
      be a key factor in deciding when to shoot, and these become more likely the longer one
      gets into the shoot clock.

      So, what this new data tells me (assuming it is for the Nets) is that the fast break is likely
      even more important for their net superiority (pun intended) that the one fifth I initially
      surmised (given that the Nets take 1.7% more first shot attempts within the first 6 seconds
      and that the 0.5 additional points per possession - turnovers included - conjecture is
      valid.)

      And regarding specific things that one should check, if one wishes to look at the value of
      Jason Kidd, it would be great to have the points per possession (turnovers included) and
      compare that to the NBA average. But then again, more data is always better.
    • Show all 81 messages in this topic