THE BOOK--Playing The Percentages In Baseball

There’s another factor at play: rule changes.  If the NBA decided that free throws were worth one million points, then I submit that we’d see the success rate on free throws increase as players are selected for free throw shooting ability.

Probably not an explanation, but it seems as if there is an inverse correlation between height and FT%.  The worst free-throw shooters are big guys like Shaq and Ben Wallace.

This could be explained away as being due to them not working on shooting away from the basket as players at other positions do, and I think that’s the most likely explanation.  But if there’s some other reason that tall players struggle at FTs (assuming they actually do), then the generational increases in height of players could be offsetting the usual skill improvement.  Again, I doubt this is the case, but thought it’d throw it out there.

I’ll agree with Sal, but also add one thing.  As time goes on, player compensation changes too.  Allen Iverson is one of the least-productive all-stars of this generation.  He makes Carlos Lee look like a sabermetrician’s MVP.  But he’s earned more than all but a handful of basketball players, in salary and sponsorship, because he’s not paid to be productive or hit free throws.  He’s paid to make ridiculous moves and hit ridiculous shots, even though he misses most of the time.

A less cynical view of the situation would be that Shaq and Ben Wallace can better help their teams by spending time practicing their rebounding or dunking.  So they may actually be performing optimally as it is.  But my hunch is that apparel and sports drink sponsorships make up a bigger part of their skill set and what they practice.

Off the wall a bit, but this made me think of Dave Pelz, who has written several books on chipping and putting in golf. He has some very specific ideas about how to practice putting, which would seem to have connections to free-throw shooting, in that they are more about skill than strength. I wonder if anyone has approached FT shooting in that way. A 5-percentage-point improvement in FT shooting would be worth about a point a game.

I’ve always thought the reason tall players do worse on free throws is solely because of selection bias.  Every 5-11 player that can’t shoot 60% doesn’t ever play in the NBA, while every 7 footer who can grab 20% of rebounds will get plenty of playing time regardless of shooting ability.  I’m not convinced that tall players have a physical disadvantage, or that they don’t try hard enough.

#5 makes a good point, and it’s not even just what tall foreign players accomplish at the line

These are all pulled from the current NBA top 50 active players in career FT%, all at least 6’10’’ (Yeah it’s arbitrary but I don’t have a bball database right now to run some height/ft% correlation. If anyone knows of any please post a link here, thanks)

5. Dirk Nowitzki: .872
17. Yao Ming: .832
26. Rashard Lewis: .807
30. Hedo Turkoglu: .800
31. Brad Miller: .800
33. Mehmet Okur: .797
35. Chris Bosh: .794
43. Troy Murphy: .783
44. Kevin Garnett: .782
46. Zydrunas Ilgauskus: .781

Graham,

I’m in the process of devising a professional basketball database. I started the project 2 years ago, and started working on it again at the beginning of this year. Right now the database is 90% complete. It is modeled after the Lahman and Baseball Databank databases. It includes statistics for the following leages:

Men

NBA (1950-present)
ABA (1968-1976)
BAA (1947-1949)
NBL (1938-1949)
ABL (1962, 1963)
PBLA (1948)
NPBL (1951)

Women

WNBA (1997-present)
ABL (1997-1999)

I also have statistics for other leagues, but they are not linked to the main database tables. I will include these leagues in seperate tables:

CBA (1991-present)
USBL (1996-present)
NBA D-LG (2002-present)
IBL (2000, 2001)
IBA (2000, 2001)
ABA2000 (2001)

ULEB Euroleague (2001-present)
ULEB Cup (2003-present)
FIBA Eurochallenge (2004-present)
FIBA Euroleague (1992-2001)

Wow terpsfan that sounds incredible. Please either email me (should be my name on this post) or post/link a website (do you have a blog or something?) when you get it online. Looking forward to it.

Won’t better shooters get fouled less, resulting in some equilibrium? Thus improved skill in shooting could still be consistent with this data.

A better way to do this would seem to be to weight the percentage by playing time (rather than number of chances). I don’t know if this will change the results.

Graham,

In the meantime, databasketball.com has a database you can download. It includes stats for the NBA, ABA, and BAA.

http://www.databasebasketball.com/stats_download.htm

You can find historical statistics for the CBA, USBL, and D-League here:

http://www.howesportsdata.com/howesportsdata/bask.htm

I just did a quick test, and weighting by playing time gives 72% for 1961-1962 and 75% for 2007-2008.

So still not a big change.

I take issue with the Iverson - Carlos Lee comparison.  Iverson was a great player.  I would compare him more to an Andre Dawson, a great player with one major flaw (OBP/FG%) but who does a lot of things well.

Iverson’s past his prime now, and he’s clearly an inferior player to Chauncy Billups after that challenge trade.  But if Iverson was not a tremendously productive player back in 2000-01, there is no way that Philly team wins 56 games and gets to the finals.

Rally,

Just because Iverson is having a subpar season this year, doesn’t mean he is past his prime. He just doesn’t fit in well with the Pistons and their painfully slow pace. In terms of efficiency, last season was his best season as a pro. He had a career-high offensive rating of 115, which is excellent considering the volume of possessions he used. He is far from over-the-hill.

Basketball Reference credited Iverson with 12.6 win shares last year, which is the highest total of his career. It is even higher than the 2001 season that Rally mentions (11.7 win shares). Maybe he has lost a step this year, but I still think his statistical decline is due to Pistons balanced style of offense.

I don’t know if anyone has mentioned this yet, but all other things being equal, a taller player has a (slight) physical disadvantage at making free throws compared to a shorter player.  This is due to the fact that a ball shot by a taller player is released at a point further from the floor, and thus will come down on to the rim at a faster velocity, making it less likely to be the beneficiary of a “shooter’s roll” if it is not a swish or near swish.  This is the main reason free-throws shot underhanded have a much higher success rate, and why really any NBA player who has a poor free throw percentage really ought to try shooting them underhanded.

This article discusses it:
“http://discovermagazine.com/2008/the-body/07-physics-proves-it-everyone-should-shoot-granny-style”

(for some reason i cannot get the links to show up on your site tango without major effort.  not sure why...)

Taking off on salb/1’s comment, Phil gives more clarity, and extra thought to the idea:
http://sabermetricresearch.blogspot.com/2009/03/free-throw-shooting-percentages-havent.html

I’d propose another explanation: foul shooting is an ancillary skill in basketball – players are chosen for their overall ability, not just their free-throw potential. And so “natural selection” won’t weed out mediocre shooters or reward the best shooters, at least not very much compared to other skills.

Compare this to other sports: bowling strikes is the primary goal of the game, the most important skill of all. And, in football, field-goal kickers are chosen for one thing: their ability to kick field goals
...
And coaches don’t force their players to shoot underhand, which would make many players more accurate; that provides support for the idea that the NBA thinks free throw percentage doesn’t matter that much.
...
I Googled “free throw shooting contest results,” and got a link to an Iowa State contest where the winner made 49 out of 50 throws. That’s 98%, and about 4 standard deviations away from the NBA average of 75%. Even considering that the contest had 72 entries, that’s pretty significant.
...
That means that over the past 58 years, players learned to convert 20% of their misses into hits. That’s pretty good. The field goal percentage improvement, from 34% to 46%, looks more impressive, but results from converting 18% of misses into hits – almost an identical improvement

Phil continues to be the best decipherer and english-explainer of all things I read.  (I presume those two words are English, or will be at some point.)

If I can draw a parallel in hockey: speed of shot.  I would guess that the average speed of a shot is probably not much different if players of the 1960s and today used the same stick.

While having a hard shot is important, accuracy is far more important. 

I would bet that there are plenty of amateurs that have a harder shot that virtually all NHL players, but they simply can’t skate well enough, or don’t have the accuracy.

I’d bet the same thing with golf, that there are tons of amateurs that can drive the ball 300-325+ yards, but lack the other basic skills to make it as a pro.

I agree that my parallels are weak, and Phil’s is much stronger.  But, if we look around, we can find probably plenty of ancillary skillset of athletes that simply don’t change as a whole, because they are simply not really selected on that basis.

Actually, the FG% was at it’s highest during the 1980’s. There was a straight-line decline in FG% from 48% in the 1980’s to 44% in 2004. The last 4 seasons have been between 45-46%. It would probably be helpful to look at both 2PT FG% and 3PT FG% separately.

basketball FG% is man v man, and so, means nothing at all in terms of evolution of offensive skill. It can simply mean an increase of defensive skill faster than offensive skill, or a defensive system, etc.

That’s why FT shooting is so fascinating because it is man v nature.

There is another aspect to consider:  the absence of underhand free throw shooters.  It’s a rare skill that can be pretty well demonstrated to improve a player’s game but won’t be adopted because of the expectation of abuse by fellow players, but this is one.  Don’t ask Rick Barry to talk about it, because he won’t stop, but the fact is that someone like Shaq could have won a lot more games in his career if he’d been willing to do it.

I think the pace of the game has something to do with it.  I think there’s probably an inverse relationship between fatigue and free throw percentage.  If the average pace of the game has quickened over time, any improvements in free throw shooting have been negated by that.

I liken it to biathalon - shooting and skiing.  The combination of a hard, physical effort requiring endurance and a fine skill like shooting.  By the end of the race you’re twitching and shaking and your accuracy goes down.  Not that I have access to biathalon-reference.com to confirm any of this…

I guess all we need to see if free throw shooting by quarter, and by starters/subs.

***

http://blogs.wsj.com/dailyfix/2009/03/09/the-count-making-the-unguarded-shot/

Can’t tell if Carl Bialik is doing this.  I guess it is, seeing the references to here and Phil’s blog.  But, I certainly am totally against the idea of no byline.  WSJ is not some faceless factory.

Unless Carl’s name is there somewhere, and it’s not apparent.

Someone made a good point regarding Shaq’s low free throw%.  Since players know that he sucks at the line, they don’t mind fouling him alot.  If he was a great free throw shooter, the dynamics as to how you’d defense against him would change dramatically.

Referring to post #7, my basketball database is 99% complete at the moment. I am looking for a free file-hosting site. Any recommendations? Even in a zipped format, the file-size is rather large. If I find a file-hosting site, I will release the first version of the database later this week. Technically it’s not really a database. It’s a bunch of CSV tables that can be linked together with a database program.

For the time being here is a rough version of my basketball database:

http://www.mediafire.com/?jntvoyxenjd

I still need to write up a readme that explains all the stats and tables. Also, I didn’t include any European stats in this first version. Finally, no advanced stats like Ortg and Pts Produced are included. I will try to include these 3 items in the next version.

Here’s the link to download version 0.2 of my basketball database:

http://www.mediafire.com/?wtjlzwzinqy

Not much is different from the last version. The Knicks recently released their media guide which had opponent stats from 1955-1970, and GS from 1965-80. I was also able to fix some individual statistical discrepancies from 1951-1964 using their media guide. Also, I fixed a few errors in the Minor League tables. I added partial playoff stats for the 1997 ABL. I was also able to reconcile the 1997 ABL individual stats as best as I could thanks to a new blogger friend I made:

http://atlantadreamblog.blogspot.com/

Here’s the link to version 0.3 of my basketball database:

http://www.mediafire.com/?tzutmuktdtm

I added stats from the Italian League (1986-87 to 2008-09), biography info for WNBA-ABL players, and a WNBA-ABL coaches table.

The statkeeping of the Italian League is nothing like the statkeeping in the US. I was able to translate all of the stat headings except for “schiacciate”, which translated as “crushed”. I have no idea what this means. Also, the Italian League keeps track of steals differently than the US leagues. The column heading for steals translated as “balls recuperated”. One more thing to keep in mind is that the team totals include team offensive and defensive rebounds, team steals, team fouls, along with team turnovers.

I added a column to the team stats, playoff team stats table called team rebounds for the seasons in which the NBA included team rebounds (deadball rebounds) in the rebounding totals for teams (1951-1968). So if you subtract tmRBD from the TRB column, you will get the total number of individual rebounds for each team during those years. In some cases they are estimates since the sum of individual rebounds aren’t available for all teams during those seasons. From 1951-1964, the NBA combined the statistics of players who played on more than one team. You will also see team rebound columns in the WNBA-ABL Teams table since the 1997 ABL counted team rebounds in the team totals.

Crush in European basketball is slam dunk

Thanks dq! I should of been able to figure that out when I saw Darryl Dawkins (Dr. Dunk) held the record for most in a season.

I noticed of a couple of errors in Dean Oliver’s stats when I was using the pythagorean theorem to figure individual wins and losses from offensive and defensive ratings. If you don’t apply both of these fixes, the individual W and L will not sum to a winning percentage of .500:

In Basketball on Paper, Dean lists .45 as the FT multiplier for defensive scoring possessions. You need to use the same multiplier you use for the offensive formulas, which is usually .4.

Also, you need to distribute the team turnovers (shot clock violations, 5 second inbound violations, 8 or 10 second halfcourt violations) to individual players. Let’s say you have a player with 250 TO, and the sum of individual turnovers for the team is 1250. His team has 60 team turnovers. This player would receive 12 additional turnovers ((250/1250)*60).