Re: My Version 2 of WINVAL
- My research in the 2002 Prospectus showed just the opposite -- that a
3-pointer had LESS chance of being rebounded than a two-point shot.
Which makes sense, because coaches are fond of saying the most
dangerous rebounder is the shooter, and on a 3-pointer the shooter is
too far away to get most rebounds.
--- In APBR_analysis@yahoogroups.com, igor eduardo küpfer
> From: "dan_t_rosenbaum" <rosenbaum@u...>thing. A
> To: <APBR_analysis@yahoogroups.com>
> Sent: Sunday, February 29, 2004 1:45 AM
> Subject: [APBR_analysis] My Version 2 of WINVAL
> > This version is possessions-based (and thus accounts for pace) and
> > also includes offensive and defensive ratings.
> > In order to make it easier to read, I just included it and my
> > comments on it on a web-page that I created. Here is the link.
> > http://www.uncg.edu/bae/people/rosenbaum/NBA/winval1.htm
> > (This thing has almost turned into a mini-paper.)
> "Mini"? :-)
> Great stuff, Dan. It will take me a few days to digest the whole
> couple of comments in passing:of three
> * <quote>
> Null Hypothesis: the cost of two point FGA is the same as the cost
> point FGAa lower
> The null hypothesis is soundly rejected with three point FGA having
> cost, even after accounting for points produced and free throwattempts
> Would it be asking too much to try this one again, this time
> rebounds in the accounting? Common Wisdom has it that 3 pointersgenerate
> more offensive rebounds, which could add to the value of the longattempts.
> (I'm aware that DeanO disputes CW in his book, and I accept hisconclusion
> that 3 misses are no more likely to be offensively rebounded than 2misses.
> Independent confirmation would be very nice, however.)opposite
> * <quote>
> Null Hypothesis: steals and turnovers have the same value, but
> It is a fairly close call, but the null hypothesis is rejected. It
> that steals help teams more than turnovers hurt teams. This couldbe because
> guys who get steals disrupt offenses in other ways that are notpicked up in
> traditional statistics.turnover,
> Is there some double counting going on here? A steal is always a
> but a turnover is not always a steal. Is it possible to isolate thetypes of
> turnovers (steals, bad pass, OFF foul, etc.) in this analysis?value
> * <quote>
> Null Hypothesis: offensive and defensive rebounds have the same
> There is no evidence to reject this hypothesis. Thus, even though
> regressions have higher coefficients for defensive rebounds (versusstatistically
> offensive rebounds), there really is no evidence to conclude
> that the value of defensive rebounds is higher than that ofoffensive
> rebounds. That said, it is very, very difficult to draw theconclusion from
> these data that offensive rebounds should be valued higher thandefensive
> rebounds, as is often argued.tentatively by
> Still a topic of great interest for me. My opinion, backed
> the data I've looked at, is that defensive rebounds have lessmarginal value
> than offensive rebounds. That is, an individual player's defensiverebound
> adds less to his team's defensive rebounding percentage than thatplayer's
> offensive rebound adds to his team's offensive reboundingpercentage. I'm
> not sure if you address this: it could be that DRebs and ORebs addthe same
> amount to a team's production, while at the same time saying each_player's_
> O and D rebounds have a different value.
- --- In APBR_analysis@yahoogroups.com, "John Hollinger"
> My research in the 2002 Prospectus showed just the opposite --that a
> 3-pointer had LESS chance of being rebounded than a two-pointshot.
> Which makes sense, because coaches are fond of saying the mostis
> dangerous rebounder is the shooter, and on a 3-pointer the shooter
> too far away to get most rebounds.This platitude surely predates the 3-point shot. And the "danger"
in a player getting a rebound may lie more in what he'll do with it,
than in the chances of his getting it.
So given that a missed 3 is no more likely (or less likely) to be
rebounded offensively, what accounts for the difference detected by
Dr. Dan ?
What about the missed shot that goes out of bounds? Probably more
likely on a 3 than on a 2. Does the defense get a rebound? No, but
effectively it's the same. Do they then get a fast break
So teams that shoot a lot of 3's may have relatively fewer fast
breaks run against them. Yet they may have relatively more
offensive rebounds. For both reasons, the outside-shooting team
gains a cushion against a bigger/stronger opponent.
This brings up the effect of "difference in team style". For a team
without inside scoring, it does make sense to shoot more long
shots. Forcing the ball inside makes the offense less efficient.
Meanwhile, it's possible for an inside-efficient team to be even
more efficient when shooting the 3. A mediocre 3-pt shooter can be
a lot better when he's wide open all day, due to doubling inside.
Smart coaches and teams take what is given them, most of the time.
For the past several years (since before the shortened-arc era of
the mid '90s), 3-pt shooting is (league-wide) more efficient than 2-
pt and FT combined.
> --- In APBR_analysis@yahoogroups.com, igor eduardo küpfer
> <edkupfer@r...> wrote:
> > From: "dan_t_rosenbaum" <rosenbaum@u...>
> > * <quote>
> > Null Hypothesis: the cost of two point FGA is the same as the
> of threehaving
> > point FGA
> > The null hypothesis is soundly rejected with three point FGA
> a lowerlong
> > cost, even after accounting for points produced and free throw
> > generated.
> > </q>
> > Would it be asking too much to try this one again, this time
> > rebounds in the accounting? Common Wisdom has it that 3 pointers
> > more offensive rebounds, which could add to the value of the
> attempts.than 2
> > (I'm aware that DeanO disputes CW in his book, and I accept his
> > that 3 misses are no more likely to be offensively rebounded
> > Independent confirmation would be very nice, however.)