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KnickerBlogger
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PostPosted: Fri Jan 21, 2005 10:19 am Post subject: Scoring Efficiency Ratings - Advancing Hollinger Reply with quote
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You can see the problem. Hollinger’s system spreads the value mostly created by O’Neal and Wade among all of the Heat free throw attempts. Further, Shaq and Wade have created 73.8% of the BFTA, but only 62.9% of the FTA for the Heat. Which leads us to two fairly obvious conclusions:
1. Not all players create BFTA at the same rate.
2. Players who can create BFTA are undervalued.
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HoopStudies
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PostPosted: Fri Jan 21, 2005 11:44 am Post subject: Reply with quote
We looked at this for, I think, the Lakers a few years ago when Stu had some similar data. It is certainly true and we should perhaps look to improve the estimation. Sounds like a good project for someone. Or did KevinP do something that I'm vaguely remembering?
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Yyzlin
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PostPosted: Fri Jan 21, 2005 2:38 pm Post subject: Reply with quote
Wouldn't the raw data that Roland has be able to help us out with this? I believe I remember somewhere, although I may be wrong, that Roland draws his data from play by play information. It seems relatively simple to record the context of every foul a player receives, since it would be part of the play-by-play. That why, you can divide it into several categories: shooting foul with missed shot, shooting foul with made shot, and non-shooting foul. If you wanted to get even more detailed, you could divide non-shooting fouls into two categories: bonus situation fouls that lead to free throws, and those that don't. And of course, you could toss technical and flagrant fouls into the mix as well, although they aren't as important because of their relative rarity.
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Nikos
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PostPosted: Fri Jan 21, 2005 3:01 pm Post subject: Reply with quote
**EDITED due to premature post....
Quote:
All free throws do not equal the same the number of possessions. Many free throws are not worth any possessions at all.
If Dwyane Wade gets fouled going to the basket, misses the shot, and gets two free throws, then those two free throws are meant to equate with the missed scoring opportunity caused by the foul. But if Wade hits the shot, and gets sent to the line for one free throw, then that one free throw isn’t meant to equate to any possessions at all. It is a bonus opportunity rewarded to Wade for making the shot while still being fouled. Anyone can take a shot, and anyone can get fouled and miss their shot, but the extra free throw is just that, it’s FREE, not compensation, a bonus that Wade created outside of the Heat’s normal possession opportunity.
Now, you may be thinking that this is not news, that this is the exact thing that Hollinger was trying to deal with having One Free Throw = 0.44 Possessions. But the problem with that number is that it takes all free throws taken everywhere and assigns them an equal, tiny share of the “bonus” value created by a much smaller number of shots. Wouldn’t it be better to reward that “bonus” value on just those shots where it was earned, and leave all other free throws equaling 0.50 free throws? Sure it would, but there’s only way one way to do that.
EDIT** -nevermind, I did not read carefully. Seems like an interesting point, now that I thought about it a bit.
And technically shouldn't these BTFA stats be easily accesible as Yyzlin said?
Last edited by Nikos on Fri Jan 21, 2005 3:13 pm; edited 2 times in total
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Yyzlin
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PostPosted: Fri Jan 21, 2005 3:09 pm Post subject: Reply with quote
Nikos wrote:
I know this is a simple concept and all, but isn't making an AND 1 just like making a three pointer? Why should those who create BFTA's matter if the player is not neccesarily MAKING the shot? Obviously an off reb could be had if the player misses the free throw, so that could skew things up as well.
Doesn't the .44 number seem just as reasonable, as opposed to giving credit to those who simply attempt bonus free throws after a made shot?
This is from what I gather. The 0.44 possessions per free throw coefficient is derived from team numbers, which tend to be heavily skewed by a few players. If someone like Damon Jones doesn't create any BFTA's (or 1 in his case based on the article), then his possessions per free throw rises to 0.5, while players like Wade and O'Neal would theoretically have lower coefficients.
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Nikos
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PostPosted: Fri Jan 21, 2005 3:11 pm Post subject: Reply with quote
Yes I agree and this is a good point, notice my edit.
I wasn't reading carefully and posted prematurely. I was trying to cover it up before anyone noticed (I figured no one probably would in time) -- but I was wrong Smile )
As an aside, should players be penalized or have their efficiencies altered if they are awarded penalty FT's based on technicals and illegal defenses? Or is the fact that they were asked to shoot them the bonus of it self, and also has value of its own? Similiar to having a go to guy on a possesion or example, going to a teams strength, in this case having the best FTer.
Bottom line: -- what if a player gets a penalty or technical FT, why should that specific FT be 0.44 considering it is not within the context of a 'convetional possesion' as it is defined in the PSA or PPFGA? Shouldn't it carry a different weight considering the only potential is to gain 1 point, and a not a full 2pts or 3 that might be obtained through a TRUE POSSESION?
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CrazyFromTheHeat
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PostPosted: Fri Jan 21, 2005 5:16 pm Post subject: Reply with quote
Hi everybody. I'm new to this site, and I appreciate everyone weighing in. I actually recorded all of the free throws based on Technicals and illegal defenses too, and then decided they weren't part of the "bonus" free throws I was looking for. In the end, technical fouls are like any other possession - your team has the ball, someone has to shoot it. If you're the shooter, then you are credited with one attempt, which becomes half of a possession, which is fair.
As for Dean's comment -sounds like a project for someone- it is, ME! But I would love some help. It's very easy, but tracking every team is too much for anyone with a job. I figure five or ten people could do the whole league fairly easily.
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Nikos
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PostPosted: Fri Jan 21, 2005 5:25 pm Post subject: Reply with quote
Crazy are you saying that tech Fts should be multipled by 0.50, and 3pt play FT's should count as .44?
Also wouldn't this whole concept hurt those who DO get to the line a lot and even for those who create BFTA? Because most FTs are normal ones anyway, so this tends to favor guys who shoot a better field goal %, as opposed to guys who get to the line a lot and convert reasonably well.
This will tend to sway more towards FG% types. For example Wade and Maggette won't seem as efficient anymore, because they get to the line a lot even without BTFA. Those extra FT's they get only represent a small percentage of their TOTAL FTA. And since they do not hit that many three pointers, they will seem less efficient than the tradional PSA indicates right now.
Wouldn't this be a pretty drastic change in many players scoring efficiencies? Now players who hit a lot of threes and get to the line are more valuable than those who might shot a real high % and get to the line (but don't hit many 3pt shots).
Last edited by Nikos on Fri Jan 21, 2005 5:36 pm; edited 1 time in total
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Ed Küpfer
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PostPosted: Fri Jan 21, 2005 5:32 pm Post subject: Reply with quote
CrazyFromTheHeat wrote:
As for Dean's comment -sounds like a project for someone- it is, ME! But I would love some help. It's very easy, but tracking every team is too much for anyone with a job. I figure five or ten people could do the whole league fairly easily.
I volunteer. My primary interest is Raptors games, but this can be done from play by play logs, right?
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CrazyFromTheHeat
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PostPosted: Fri Jan 21, 2005 5:51 pm Post subject: Reply with quote
Wish me luck with the "quotes" thingy. If it doesn't come out well I'll do it again.
Nikos wrote:
Crazy are you saying that tech Fts should be multipled by 0.50, and 3pt play FT's should count as .44?
Tech fouls by 0.50, 3pt FT are counted as part of the "bonus" ones, more completely defined as "free throws after made shots".
Nikos wrote:
CrazyAlso wouldn't this whole concept hurt those who DO get to the line a lot and even for those who create BFTA? Because most FTs are normal ones anyway, so this tends to favor guys who shoot a better field goal %, as opposed to guys who get to the line a lot and convert reasonably well.
This will tend to sway more towards FG% types. For example Wade and Maggette won't seem as efficient anymore, because they get to the line a lot even without BTFA. Those extra FT's they get only represent a small percentage of their TOTAL FTA.
The data shows the opposite, but you may be thinking that because the formula hasn't been posted here. Here it is:
Shooting Efficiency = Total Points divided by [FGA + ((FTA - BFTA) divided by two)]
So what happens is, a whole mess of Wade's free throws gets lopped off of his attempts (because they weren't part of the possession), making the number we're dividing by less, which then makes his final Scoring Efficiency Rating higher.
Nikos wrote:
CrazyWouldn't this be a pretty drastic change in many players scoring efficiencies? Now players who hit a lot of threes and get to the line are more valuable than those who might shot a real high % and get to the line (but don't hit many 3pt shots).
It wouldn't change the ratings much at all, except for those guys who score and get fouled a lot. If there were one main conclusion I could draw from this whole thing, it would be that players who can draw fouls and still score are being undervalued.
Sure hopes this prints well.
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CrazyFromTheHeat
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PostPosted: Fri Jan 21, 2005 5:53 pm Post subject: Reply with quote
Ed Küpfer wrote:
CrazyFromTheHeat wrote:
As for Dean's comment -sounds like a project for someone- it is, ME! But I would love some help. It's very easy, but tracking every team is too much for anyone with a job. I figure five or ten people could do the whole league fairly easily.
I volunteer. My primary interest is Raptors games, but this can be done from play by play logs, right?
Cool! Thanks Ed! Yes, it's all on play logs. Email me and I'll break it all down for you. To throw in a little of my Boston lingo, it's wicked easy.
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Nikos
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PostPosted: Fri Jan 21, 2005 6:01 pm Post subject: Reply with quote
Crazy
What I am saying is that this might all EVEN out, even if you factor BTFA. Because BTFA usually are a small portion of the players FTs. So how can it really help THAT much? If most of the FTs they take are regular and multipled by .50, then its more likely it could hurt them, unless players who get to the line a lot less are getting a much less proportinal BTFA's while still taking a lot of FG's.
Or perhaps its a bell shape thing that affects certain people who might have a high or low BTFA relative to FTA. I wonder if there is a somewhat linear relationship for those who get lots of FTA in relation to BTFA's.
Can you give us the old and new PSA's for the Miami Heat so we can apply this example and to see which players might be undervalued or overvalued?
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Nikos
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PostPosted: Fri Jan 21, 2005 6:25 pm Post subject: Reply with quote
I ran a quick PSA comparison based on your BTFA's. It all depends I guess on the frequency with which you get to the line and your % when you get there. And if there is a close relationship to guys who take a lot of FT's relative to FGA's, then it makes sense that guys who get fouled and MAKE FTs are undervalued.
Damon Jones got affected the most in terms of the starting 5. I'll try and post my chart using Tabs2Spaces, but Im not sure how to.
From what I have Shaq's NEW PSA took a larger dip than Wade's because of his poor FT shooting %. So I guess it is more sensitive to those who get to the line a lot and miss.
So I guess in general it may be true that it does undervalue those who get a lot of BFTA, and especially those who shoot a good %. From Miami, it seems that whoever gets to the line a lot seems to have between 10-12% BFTA. If this holds true, than for the most part all good FT shooters who get to the line a lot are undervalued. Unless there are some bizarre cases where players get to the line and a lot, but have hardly any BTFA's. I guess we would have to study all the teams to find this out.
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CrazyFromTheHeat
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PostPosted: Fri Jan 21, 2005 8:05 pm Post subject: I can't believe it Reply with quote
Here are the raw numbers on bonus free throws for the Heat:
Shaq 49
Wade 41
Haslem 14
E Jones 11
Laettner 3
Doleac 1
D Jones 1
Butler 1
Anderson 1
So we obviously have guys accumulating bonus free throws at different rates, right? And that's bound to make a difference, right? Well, I ran the numbers for my system and Hollinger's, and the results are remarkable. All numbers are points per possession.
Shaq - me 1.17, JH 1.17
Wade - me 1.14, JH 1.14
Haslem - me 1.17, JH 1.17
EJ - me 1.05, JH 1.05
DJ - me 1.20, JH 1.21
Laettner - me 1.22, JH 1.23
Butler - me 1.06, JH 1.07
Doleac - me 1.00, JH 1.01
Dooling - me 0.87, JH 0.89
Anderson - me 0.94, JH 0.95
Allen - me 1.08, JH 1.09
Person - me 1.04, JH 1.04
Wang - me 1.25, JH 1.28
If anything, the 0.44 number overcompensates, so that what happens is that players who don't get to the line see their number drop a little with my system, but no one benefits. Very discouraging. I thought there would be more of a difference, but I guess not.
Maybe the positive is that I've proven the effectiveness of Hollinger's 0.44 number.
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Nikos
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PostPosted: Fri Jan 21, 2005 8:29 pm Post subject: Reply with quote
Yea the differences are not very large, if at all. Thats why I started before, that it all pretty much levels out even though the .44 doesn't make sense in the sense of when your watching the game.
The guys who are affected the most on the Heat are Laetner and D.Jones I beleive.
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PostPosted: Sat Jan 22, 2005 3:14 am Post subject: Reply with quote
To emphasize what's already been said about the differences not being very large:
Code:
Player BTFA FTA Ratio ePos aPos
----------------------------------------------
O'Neal 49 427 0.115 187.9 189.0
Wade 41 347 0.118 152.7 153.0
Haslem 14 123 0.114 54.1 54.5
Ejones 11 113 0.097 49.7 51.0
Laettner 3 32 0.094 14.1 14.5
Doleac 1 24 0.042 10.6 11.5
Djones 1 47 0.021 20.7 23.0
Butler 1 31 0.032 13.6 15.0
Anderson 1 21 0.048 9.2 10.0
Dooling 0 48 0.000 21.1 24.0
Allen 0 10 0.000 4.4 5.0
Person 0 4 0.000 1.8 2.0
Wang 0 4 0.000 1.8 2.0
Looking at the raw data, it looks like Shaq and Wade create a ton more BFTAs, but the fact is they create a ton more free throws in general. Generally speaking, the same qualities that earn three-point plays also earn two free-throw attempts.
John Hollinger actually did study this issue in the first Prospectus, finding similar results, but it's good to look at it again. One thing that I don't think has been resolved to my satisfaction, unless my reading comprehension is poor -- what about three-shot fouls?
John argues players should only get credit for technical FTs where their overall percentage is above the league average. That is a fairer opportunity cost than one point -- the opportunity is not making the free throw, but having someone else take it. I'm not sure if it's better to use league average or some "replacement-level" free-throw percentage.
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Mike G
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PostPosted: Sat Jan 22, 2005 8:00 am Post subject: Reply with quote
Wow, things move fast here! I went ahead and replied on the Heat board before I finished reading the thread here.
We concur that .44 is a very satisfactory multiplier for the Big 2, Wade and Shaq. This implies that these guys get 12% of their FT as and-1s.
However, the team totals are (before last night) 1231 FTA and 122 BFTA. That's almost exactly 10%, implying a multiplier of .45 .
I'll guess the difference between getting the respect (and getting the call), and not getting the respect is believably within that range of 20% more calls for a Wade than for a Dooling.
A range of .44-.45 may be good enough. Or there may be other factors to tease out; such as a ratio of assists/points: a ballhandler/distributor is more likely to get fouled before he's attempting a shot. A guy with postup game might get fewer shooting fouls than a slasher.
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Ed Küpfer
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PostPosted: Sat Jan 22, 2005 1:16 pm Post subject: Reply with quote
I compiled a list of every and-1 and technical FTA from all the games in November and December (except two, if anyone wants to go ahead and do those). I don't have time for any analysis but I'll make the data available. The csv is on my Yahoo site.
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Kevin Pelton
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PostPosted: Sat Jan 22, 2005 2:01 pm Post subject: Reply with quote
Thinking aloud a little bit ... there's another distinction we can make here, which is how two-shot fouls were "gotten", for lack of a better word. Some come when a player is fouled in the act of shooting, but you have other scenarios like the end of games when teams foul intentionally.
Is it reasonable to think that a player like Damon Jones is shooting most of his free throws in these situations and that's why his BFTA/FTA ratio is so low? That three-point plays and shooting fouls are relatively evenly distributed (besides luck in this small of a sample size) and guys like Jones just have really low shooting foul ratios?
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CrazyFromTheHeat
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PostPosted: Sat Jan 22, 2005 7:51 pm Post subject: Reply with quote
admin wrote:
Thinking aloud a little bit ... there's another distinction we can make here, which is how two-shot fouls were "gotten", for lack of a better word. Some come when a player is fouled in the act of shooting, but you have other scenarios like the end of games when teams foul intentionally.
To me, free throws from intentional fouls should count the same as the regular ones. In the end, this becomes the possession, and the player still has the responsibility of making the shots. It only matters whether or not the foul was intentional if you're talking about something like shot creation, which is a much messier topic.
admin wrote:
Is it reasonable to think that a player like Damon Jones is shooting most of his free throws in these situations and that's why his BFTA/FTA ratio is so low? That three-point plays and shooting fouls are relatively evenly distributed (besides luck in this small of a sample size) and guys like Jones just have really low shooting foul ratios?
I can't back this statistically, but I think its because an overwhelming proportion of DJ's baskets come on "open" shots. He gets a ton of them in the Heat's half-court offense, and the few times he shoots with a hand in his face he usually misses. Also, he never drives to the basket, so his chances for BFTA are minimal. One of the things I like about the BFTA results is that so far they have come out pretty much as you would expect from just observation.
And going back a few notes to times when a player attempts 3 free throws, I counted the third one as BFTA, the reasoing being that if you counted it as a regular free throw, the three free throws would equal 1.5 possessions, which they obviously aren't.
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Kevin Pelton
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PostPosted: Sat Jan 22, 2005 8:00 pm Post subject: Reply with quote
CrazyFromTheHeat wrote:
Also, he never drives to the basket, so his chances for BFTA are minimal.
At the same time, so should his chances for any free-throw attempts be minimal. What I'm arguing is that few players really have a "skill" for getting three-point plays; drawing the shooting fouls is the skill, and sometimes the shot happens to bounce in.
But we can't just look at free throws attempted to measure the "free-throw drawing" skill, because a player like Jones, I suspect, will take a significant percentage of his free-throws off of intentional fouls.
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CrazyFromTheHeat
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PostPosted: Sat Jan 22, 2005 8:31 pm Post subject: Reply with quote
[quote="admin What I'm arguing is that few players really have a "skill" for getting three-point plays; drawing the shooting fouls is the skill, and sometimes the shot happens to bounce in.[/quote]
But that would imply that players should accumulate BFTAs at the same rate, and they don't. Here are the Heat players BFTA Percentages (percentage of total FT), listed with their number of FTA in front of their names:
427 Shaq 11.48
347 Wade 11.82
123 Haslem 11.38
113 E Jones 9.73
48 Dooling 0.00
47 D Jones 2.13
32 Laettner 9.38
31 Butler 3.23
24 Doleac 4.17
21 Anderson 4.76
10 Allen 0.00
4 Person 0.00
Wang 0.00
The real interesting one is Dooling. He's hardly ever on the floor at the end of games, drives to the basket better than anyone on the team other than Wade and possibly EJ, and still can't accumulate a single BFTA. It's a small sample, but it does suggest that getting fouled and getting the basket is a skill.
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Ed Küpfer
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PostPosted: Sat Jan 22, 2005 9:07 pm Post subject: Reply with quote
Argh. A mistake creeped into my data, giving Josh Childress of all people credit for and-1s that he didn't take. Don't use the data I uploaded to the Yahoo site, I'm fixing the mistakes now.
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Ed Küpfer
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PostPosted: Sun Jan 23, 2005 6:42 pm Post subject: Reply with quote
Okay, I fixed the data. The file now has the details of every free throw attempted this season, until Jan 21. The csv uses the following format:
Code:
DATE AWAY HOME PLAYER TEAM SHOT# #SHOTS TYPE Q TIME
04-11-02 DEN LAL anthony,carmelo DEN 1 2 Shooting 1 10:40
04-11-02 DEN LAL anthony,carmelo DEN 2 2 Shooting 1 10:40
04-11-02 SAC DAL dampier,erick DAL 1 2 Shooting 1 9:56
04-11-02 SAC DAL dampier,erick DAL 2 2 Shooting 1 9:56
04-11-02 HOU DET wallace,ben DET 1 1 Shooting 1 9:18
DATE, AWAY, HOME, PLAYER, TEAM should be obvious. SHOT# is the shot sequence, eg 1=front end of a two-shot scenario and the FTA on an AND-1. #SHOTS is the total number of FTAs in that sequence. TYPE is the foul description displayed on the nba.com PBP logs. They've used the following:
TYPE
Away from Play
Clear Path
Delay Technical
Double Technical
Elbow
Flagrant Type 1
Flagrant Type 2
Hanging Technical
Illegal Defense
Inbound
Loose Ball
Non Supported Technical
Offensive
Personal
Punching
Shooting
Taunting Technical
Technical
Q is the quarter in which the FTs were attempted, TIME is the time remaining in the quarter.
Here's a direct link to the file, which probably won't work. If not, you can look around here and download the file titled "and1s.csv".
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Ed Küpfer
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PostPosted: Sun Jan 23, 2005 7:38 pm Post subject: Reply with quote
Here's how the types of FTs break down:
Code:
FTAs
TYPE 1 2 3 TOTAL
Away from Play 35 4 0 39
Clear Path 28 0 0 28
Delay Technical 4 0 0 4
Double Technical 1 0 0 1
Elbow 0 4 0 4
Flagrant Type 1 0 77 0 77
Flagrant Type 2 0 12 0 12
Hanging Technical 12 0 0 12
Illegal Defense 341 0 0 341
Inbound 0 24 0 24
Loose Ball 3 1002 0 1005
Non Supported Technical 2 0 0 2
Offensive 0 8 0 8
Personal 8 6628 3 6639
Punching 2 0 0 2
Shooting 2473 18578 303 21354
Taunting Technical 6 0 0 6
Technical 446 0 0 446
TOTAL 3361 26337 306 30004
The FTAs that represent the end of a possession -- Shooting, Loose Ball, Away from Play, and Personal -- sum to 13259, or 44.2% of the total. Nice to have that FTA coefficent confirmed.
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Ed Küpfer
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PostPosted: Sun Jan 23, 2005 8:54 pm Post subject: Reply with quote
I've uploaded a csv with showing a breakdown of every player's FTA -- how many and-1s, how many techs, etc. It's at the Yahoo site I linked to above.
The leaders in in BFTA%, or "and-1%":
Code:
PLAYER BFTA FTA BFTA%
brand,elton 35 223 15.7%
mohammed,nazr 20 132 15.2%
curry,eddy 24 162 14.8%
stoudemire,a 54 388 13.9%
jamison,antawn 21 156 13.5%
odom,lamar 24 180 13.3%
miller,andre 20 150 13.3%
martin,kenyon 20 153 13.1%
hill,grant 22 173 12.7%
wallace,ben 13 105 12.4%
haslem,udonis 16 130 12.3%
wallace,gerald 15 123 12.2%
miller,brad 22 182 12.1%
sweetney,mike 12 102 11.8%
wade,dwyane 42 359 11.7%
williamson,c 13 112 11.6%
stojakovic,peja 17 151 11.3%
okafor,emeka 18 161 11.2%
marbury,stephon 24 215 11.2%
o'neal,shaq 49 440 11.1%
Andre Miller?
The lowest BFTA% among players with 100+FTAs:
Code:
PLAYER BFTA FTA BFTA%
boykins,earl 3 115 2.6%
hamilton,r 7 253 2.8%
croshere,austin 5 130 3.8%
nailon,lee 4 100 4.0%
billups,c 8 185 4.3%
collins,jason 5 105 4.8%
alston,rafer 6 124 4.8%
allen,ray 11 226 4.9%
nash,steve 5 102 4.9%
fisher,derek 5 101 5.0%
okur,mehmet 9 180 5.0%
dampier,erick 6 120 5.0%
brown,p.j. 6 116 5.2%
turkoglu,hedo 6 115 5.2%
iverson,allen 21 360 5.8%
williams,eric 8 137 5.8%
blount,mark 6 102 5.9%
brezec,primoz 6 102 5.9%
abdur-rahim,s 6 101 5.9%
hinrich,kirk 7 112 6.3%
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CrazyFromTheHeat
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PostPosted: Sun Jan 23, 2005 10:06 pm Post subject: Reply with quote
Wow Ed! You're my hero. I can't wait to get started with all of that data. One thing that jumps out at me right away is Iverson among the lowest. Who would have guessed that?
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Nikos
Joined: 16 Jan 2005
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PostPosted: Mon Jan 24, 2005 12:08 am Post subject: Reply with quote
Hey Ed can you post ther attachment of all players BFTA?
Also when you get the chance post the W-L %s on your site, that addition would make it near flawless.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 1:44 am Post subject: Reply with quote
admin wrote:
What I'm arguing is that few players really have a "skill" for getting three-point plays; drawing the shooting fouls is the skill, and sometimes the shot happens to bounce in.
Well, Ed's data isn't helping this hypothesis, though I suppose we'd have to see a couple of seasons worth of data to see whether there is year-to-year consistency. ...
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Mike G
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PostPosted: Mon Jan 24, 2005 8:54 am Post subject: Reply with quote
Ed Küpfer wrote:
The FTAs that represent the end of a possession -- Shooting, Loose Ball, Away from Play, and Personal -- sum to 13259, or 44.2% of the total. Nice to have that FTA coefficent confirmed.
Using Ed's data, I figured this somewhat differently.
Since we are looking for a multiplier to apply to 1 FTA that makes it equivalent to 1 FGA, I look for a departure from 2 FTA in the average possession-ending foul.
From the total of not-in-the-act fouls (personals, loose ball, and inbounds) and act-of-shooting fouls, I subtract "bonus" FT (and-1s, 3rd of 3-shot FTA); and divide by the total FTA:
(7654 + 21354 - 2473 - 101) / 30004 = .881
101 is 1/3 of 303 3-shot fouls.
7654 is # of non-shooting 2-shot fouls.
Half of .881 is .4405, so we are corroborated.
(I didn't include "away from play" fouls in the possession-ending category
: 35 of 37 were 1-shot fouls. I'm not familiar with this call, actually.)
How do we get an odd number (77) of FTA from flagrant-1's ? I can see a teammate stepping into the lane and nullifying some FTA -- but not a T.
As to the wide range of BFTA/FTA, clearly there are 2 skills at work: drawing the foul, and finishing the shot. Iverson draws fouls and flings up prayers. Shaq tends to score with guys hanging on him.
Shaq might be at the top of the list if his FTA weren't diluted with hackashaq plays. No chance for a bonus shot there.
There are quite a range of "ballhandling" fouls still in the mix (undifferentiated from "shooting" fouls.) I suspect these are more significant than differences in "finishing strength".
Scoring Eff. Ratings- Advancing Hollinger (KnickerBlogger)
Scoring Eff. Ratings- Advancing Hollinger (KnickerBlogger)
Last edited by Crow on Wed May 11, 2011 5:43 pm, edited 1 time in total.
Re: Scoring Efficiency Ratings - Advancing Hollinger
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Ed Küpfer
Joined: 30 Dec 2004
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PostPosted: Mon Jan 24, 2005 11:22 am Post subject: Reply with quote
Nikos: The data you want is at this Yahoo site.
MikeG: I found the error. In row 10398, there is the following record:
Code:
04-11-28 IND SEA harrison,david IND 1 1 Technical 2 9:45
That should read:
Code:
04-11-28 IND SEA harrison,david IND 1 2 Flagrant Type 1 2 9:45
Which means that David Harrison gets one more Flagrant 1 FTA (total = 2) and one fewer technical FTA (total = 0). I've updated the files at Yahoo to reflect the changes, or you can just change it on the copy you have now.
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CrazyFromTheHeat
Joined: 21 Jan 2005
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PostPosted: Mon Jan 24, 2005 9:26 pm Post subject: Reply with quote
Mike G wrote:
As to the wide range of BFTA/FTA, clearly there are 2 skills at work: drawing the foul, and finishing the shot. Iverson draws fouls and flings up prayers. Shaq tends to score with guys hanging on him.
I agree with this, except that you could say the same thing about other prominent players, and they don't show up on the "low" leaders board. Iverson's total number of attempts really stands out compared to the others on that list.
Mike G wrote:
Shaq might be at the top of the list if his FTA weren't diluted with hackashaq plays. No chance for a bonus shot there.
Good point. In his case, it might be more important to look at total number of BFTAs, where he is second to Stoudamire.
Mike G wrote:
There are quite a range of "ballhandling" fouls still in the mix (undifferentiated from "shooting" fouls.) I suspect these are more significant than differences in "finishing strength".
There's another great study right there - ability to draw fouls. It's all in the play logs, we just need the time and desire to count it. Of course, we could just ask Ed, and he'd probably have it for us tomorrow.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 10:18 pm Post subject: Reply with quote
To take out the effect of the ballhandling or Hack-a-Shaq fouls, all we need to do is change the denominator from all FTAs to Shooting FTAs, right? Let's see how that changes the leaderboard (I've also reduced minimum FTA to 50):
Code:
Player BFTA SFTA Pct
----------------------------
Jamison 21 98 21.4
JRose 17 81 21.0
Stoudamire 6 29 20.7
JSmith 13 63 20.6
Knight 9 45 20.0
Artest 6 30 20.0
JSmith 12 62 19.4
JuHoward 10 52 19.2
GWallace 15 79 19.0
Brand 35 185 18.9
Only 29 of Stoudamire's 71 free throws have been of the shooting variety.
Code:
Player BFTA SFTA Pct
----------------------------
Cardinal 0 50 0.0
Marshall 0 52 0.0
JrCollins 0 53 0.0
Lue 0 56 0.0
Hart 0 78 0.0
Cato 1 62 2.1
QRichardson 2 99 2.4
ADavis 1 54 2.7
Udrih 1 50 2.9
Ely 2 74 3.8
Shaq, incidentally, is at 15.8%, tied for 33rd with LeBron James ... and Jeff McInnis.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 10:30 pm Post subject: Reply with quote
We can also look at the ratio of shooting free throw attempts to total free throw attempts, which turns out to be pretty interesting:
Code:
Player SFTA FTA Pct
---------------------------
Drobnjak 66 72 91.7
ECurry 148 162 91.4
Mihm 125 137 91.2
Stoudemire 354 388 91.2
Mohammed 120 132 90.9
Ratliff 56 62 90.3
Sweetney 92 102 90.2
Ilgauskas 221 246 89.8
Fortson 165 185 89.2
LWright 57 65 87.7
This bears a suspicious resemblence to the original BFTA% list, for good reason -- it measured more the ability to get a lot of shooting fouls than to really convert fouls while shooting into makes.
Code:
Player SFTA FTA Pct
---------------------------
DJones 7 50 14.0
Atkins 29 86 33.7
Nash 35 102 34.3
Boykins 41 115 35.7
Hart 28 78 35.9
RMiller 27 70 38.6
Stoudamire 29 71 40.8
Posey 23 56 41.1
Ridnour 32 74 43.2
Van Exel 22 50 44.0
See, I did know something! Damon Jones isn't really that bad at converting BFTA opportunities; he's just only been fouled in the act of shooting only four times all season. (That's once every 329.5 minutes.)
Incidentally, there still must be some errors in the NBA's data. I'm not sure how exactly one shoots free throws on double technicals or offensive fouls. Not a big deal, since there's only a handful of them, but still the case.
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 10:45 pm Post subject: Reply with quote
admin wrote:
Incidentally, there still must be some errors in the NBA's data. I'm not sure how exactly one shoots free throws on double technicals or offensive fouls.
That's sweet of you to blame the NBA for the errors, but I assure you they're almost certainly mine. WRT to double-Ts, I'll comb the logs now to find the mistakes. Updates here.
However, the offensive fouls are real: if the team is in the penalty, the defensive team will shot FTs. Check out the action at the 0:19 mark of the 4th in this game.
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 10:59 pm Post subject: Reply with quote
Error found! Row 23350 reads:
Code:
05-01-04 PHX MIN outlaw,bo PHX 1 1 Double Technical 4 5:09
Should read:
Code:
05-01-04 PHX MIN outlaw,bo PHX 1 1 Shooting 4 5:09
That is the only Double-T. Files at Yahoo site updated to reflect changes. Further corrections gleefully accepted.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 11:11 pm Post subject: Reply with quote
That's a mistake in the play-by-play. Offensive fouls are not team fouls, thus no shots can be attempted on them:
Quote:
PENALTIES: The offender is charged with a personal foul. The offended team is charged with a team foul if the illegal contact was caused by the defender. There is no team foul if there are personal fouls on one member of each team or the personal foul is against an offensive player.
http://www.nba.com/analysis/rules_12.ht ... rticleList
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 11:17 pm Post subject: Reply with quote
admin wrote:
That's a mistake in the play-by-play. Offensive fouls are not team fouls, thus no shots can be attempted on them
Ah well, what do I know. Luckily they only make up 8 of the FTAs in my sample.
In other news, I've uploaded a zip file containing all the logs I used to compile the data, if anyone wants to have a go. It's at the Yahoo site.
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HoopStudies
Joined: 30 Dec 2004
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PostPosted: Tue Jan 25, 2005 12:45 pm Post subject: Reply with quote
Ed Küpfer wrote:
In other news, I've uploaded a zip file containing all the logs I used to compile the data, if anyone wants to have a go. It's at the Yahoo site.
There are other errors with these logs, most pretty minor.
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
- They are inconsistent in their naming, somewhat understandably. If Cleveland is playing Seattle, Lebron James is listed as L. James to avoid confusion with J. James. But he's listed as just James in most games.
- I've noticed once that their labeling of what period it is is wrong.
Then, of course, there are times when the wrong person is credited with something. This is not correctable because it's also done in the official stats, but fortunately rare. Well, it's rare for things like assists and rebounds, but it still seems to me that a fair number of steals are credited to the person least responsible for it.
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Ed Küpfer
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PostPosted: Tue Jan 25, 2005 3:15 pm Post subject: Reply with quote
HoopStudies wrote:
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
Yeah, those are strange. This is one of the reasons mining PBP logs is such a chore for me. I wonder if the ESPN.com logs have this problem.
HoopStudies wrote:
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
Those aren't really a problem, unless you're logging the types of shots taken.
HoopStudies wrote:
- They are inconsistent in their naming, somewhat understandably. If Cleveland is playing Seattle, Lebron James is listed as L. James to avoid confusion with J. James. But he's listed as just James in most games.
The convention for NBA.com logs, if anyone is interested, is that if there is more than one player with the same last name on both teams playing, their surnames will be preceded by their first initial, a period, and a space. Otherwise, only their surnames will be shown.
What makes it difficult is some teams, during the course of the season, have two players with the same surname playing for them -- but not at the same time. For example, Steve Smith has played all season for the Bobcats. Until Dec 14, he would show up in the log as "Smith." After Dec 14, Theron Smith began playing for the team, and Steve's name was displayed under "S. Smith." At the end of the season, looking back at the games prior to December 14, you would have no idea which "Smith" it was to which the logs refered. You would have to look at the boxscores to see which one played. PITA.
HoopStudies wrote:
- I've noticed once that their labeling of what period it is is wrong.
Never seen that one. I'll keep an eye out.
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HoopStudies
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PostPosted: Tue Jan 25, 2005 4:08 pm Post subject: Reply with quote
Ed Küpfer wrote:
HoopStudies wrote:
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
Yeah, those are strange. This is one of the reasons mining PBP logs is such a chore for me. I wonder if the ESPN.com logs have this problem.
The QC on this one is straightforward, fortunately.
Ed Küpfer wrote:
HoopStudies wrote:
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
Those aren't really a problem, unless you're logging the types of shots taken.
Depends on what you're doing. It causes me QC problems.
Ed Küpfer wrote:
HoopStudies wrote:
- I've noticed once that their labeling of what period it is is wrong.
Never seen that one. I'll keep an eye out.
I remember a case where the 1st period was labeled as the 2nd period. I think they then had 2 fourth periods.
Sportsline and ESPN both have different info. ESPN has no info on shot type, but has distance. Sportsline has shot type but little of several other things. Sportsline has shot charts that are nice, too.
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CrazyFromTheHeat
Joined: 21 Jan 2005
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PostPosted: Tue Jan 25, 2005 8:48 pm Post subject: Reply with quote
admin wrote:
Damon Jones isn't really that bad at converting BFTA opportunities; he's just only been fouled in the act of shooting only four times all season. (That's once every 329.5 minutes.)
The trick with this is, there's a reason why DJ has only been fouled four times in the act of shooting all year. If DJ believed that he could get to the line regularly by driving to the basket regularly, then he would. He's not refusing to come inside the arc just because he's so good out there, he's doing it because he knows he has little chance of success in traffic.
A similar scenario would be saying that Shaq might be a good three-point shooter, we just don't know because he hasn't tried any. But we know that Shaq stays close to the basket because that's his best chance of success, and that if he started breaking the backboard with threes then he would diminish his value. DJ is the same way. He doesn't accumulate BFTAs because it's not what he does well, not because he isn't given an opportunity.
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Dan Rosenbaum
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PostPosted: Tue Feb 01, 2005 3:06 pm Post subject: Reply with quote
Ed Küpfer wrote:
Here's how the types of FTs break down:
Code:
FTAs
TYPE 1 2 3 TOTAL
Away from Play 35 4 0 39
Clear Path 28 0 0 28
Delay Technical 4 0 0 4
Double Technical 1 0 0 1
Elbow 0 4 0 4
Flagrant Type 1 0 77 0 77
Flagrant Type 2 0 12 0 12
Hanging Technical 12 0 0 12
Illegal Defense 341 0 0 341
Inbound 0 24 0 24
Loose Ball 3 1002 0 1005
Non Supported Technical 2 0 0 2
Offensive 0 8 0 8
Personal 8 6628 3 6639
Punching 2 0 0 2
Shooting 2473 18578 303 21354
Taunting Technical 6 0 0 6
Technical 446 0 0 446
TOTAL 3361 26337 306 30004
The FTAs that represent the end of a possession -- Shooting, Loose Ball, Away from Play, and Personal -- sum to 13259, or 44.2% of the total. Nice to have that FTA coefficent confirmed.
This is in response to a question that I got from DeanO through e-mail. When comparing teams, I compute true shooting percentage separately for two point attempts and three point attempts. But this raises a question. How do I allocate free throws between two point and three point attempts?
Two-point attempt free throws (possessions in parentheses)
Clear Path and Flagrant Fouls: 117 (0)
Shooting - 2 shot: 18,578 (9,289)
Shooting - 1 shot: 2,460 (0)
Total: 21,155 (9,289)
Three-point attempt free throws (possessions in parentheses)
Personal - 3 shot: 3 (1)
Shooting - 3 shot: 303 (101)
Shooting - 1 shot: 13 (0)
Total: 319 (102)
Unallocated (possessions in parentheses)
Away from Play - 1 shot: 35 (0)
Away from Play - 2 shots: 4 (2)
Technicals, Punching, and Illegal Defense: 814 (0)
Elbow: 4 (2)
Inbound: 24 (12)
Offensive: 8 (4)
Loose Ball - 1 shot: 3 (0)
Loose Ball - 2 shot: 1002 (501)
Personal - 1 shot: 2 (0)
Personal - 2 shots: 6,628 (3,314)
Total: 8,530 (3,835)
-- I tended to try to overallocate to two pointers, allocating all clear path and flagrant fouls to two point attempts.
-- I allocated 13 Shooting - 1 shot fouls to three pointers assuming that the odds of making a three-pointer when fouled was half that of making a two-pointer when fouled. This is only 13 free throws, so it is not a big deal whatever I do.
Now clearly there are some screwy categories here, and I am sure a handful of free throws are misallocated, but I think this is basically right. In essence, most free throws are fall in the two point attempt and unallocated categories. There are very few in the three point attempt category.
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
This would differ by team and would be different on offense and defense for a given team, but for an example, we can do this with the league averages.
As of January 31, about 80.6 percent of field goal attempts in 2004-05 were two point attempts, leaving 19.4 percent as two point attempts. Thus, this would result 6,878 of the unallocated free throws (and 3,092 of the unallocated possessions) being allocated to two pointers and 1,652 of the unallocated free throws (and 743 of the unallocated possessions) being allocated to three pointers.
Thus, after allocation here are the totals (with possessions in parentheses).
Two-point attempts: 28,033 (12,381)
Three-point attempts: 1,971 (845)
Note that this results in a possession multiplier of 0.442 for two point free throw attempts and 0.429 for three point free throw attempts.
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gabefarkas
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PostPosted: Tue Feb 01, 2005 5:08 pm Post subject: Reply with quote
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
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Dan Rosenbaum
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PostPosted: Tue Feb 01, 2005 5:15 pm Post subject: Reply with quote
gabefarkas wrote:
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
I think the consensus is that technicals count as zero possessions. In general, the possession of the ball does not change from one team to the other during a technical, flagrant, etc. Counting them as zero possessions is one of the reasons why free throw attempts count, on average, only 0.44 possessions.
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Ed Küpfer
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PostPosted: Tue Feb 01, 2005 5:33 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
Note that this results in a possession multiplier of 0.442 for two point free throw attempts and 0.429 for three point free throw attempts.
Nice. I've updated my web page so that team possessions calculations use a weighted average of those two coefficients.
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gabefarkas
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PostPosted: Wed Feb 02, 2005 6:56 am Post subject: Reply with quote
Dan Rosenbaum wrote:
gabefarkas wrote:
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
I think the consensus is that technicals count as zero possessions. In general, the possession of the ball does not change from one team to the other during a technical, flagrant, etc. Counting them as zero possessions is one of the reasons why free throw attempts count, on average, only 0.44 possessions.
so even if a team scores a point on a FTM, it's rolled into the next possession.
even with stuff like Floor%?
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CrazyFromTheHeat
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PostPosted: Thu Feb 03, 2005 10:33 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
Instead of the 75/25 split, wouldn't it be more accurate to split it along the lines of 21,155/319, or 98.5/1.5, the split between free throws from twos and threes? One thing we do know is that a very small percentage of free throws are associated with threes, so giving them 25 % of unallocated free throws seems very generous.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 12:26 am Post subject: Reply with quote
CrazyFromTheHeat wrote:
Dan Rosenbaum wrote:
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
Instead of the 75/25 split, wouldn't it be more accurate to split it along the lines of 21,155/319, or 98.5/1.5, the split between free throws from twos and threes? One thing we do know is that a very small percentage of free throws are associated with threes, so giving them 25 % of unallocated free throws seems very generous.
I am only allocating the free throws that cannot be allocated to either two pointers or three pointers - mostly the non-shooting fouls. I am not allocating all free throws.
I guess I don't understand the point that a foul in the backcourt that leads to free throws or a technical free throw should almost always be allocated to two pointers. Many of those possessions end up in three point attempts. To me it makes more sense it just makes sense to allocate them in the proportion in which field goal attempts end up being two pointers or three pointers. Otherwise, I think we bias ourselves into thinking that two pointers are more efficient than they really are. My allocation method, in essence, does not allow these unallocated free throws to have an effect on the relative efficiency of two pointers vs. three pointers. That seems more reasonable to me.
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Kevin Pelton
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PostPosted: Fri Feb 04, 2005 12:51 am Post subject: Reply with quote
Dan - I'd add a very minor quibble: Shouldn't we add in the already allocated two-point FTA and three-point FTA along with two-point FGA and 3PA? The 75/25 would seem to very slightly underrate the number of possessions which end up inside the three-point line.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 1:24 am Post subject: Reply with quote
admin wrote:
Dan - I'd add a very minor quibble: Shouldn't we add in the already allocated two-point FTA and three-point FTA along with two-point FGA and 3PA? The 75/25 would seem to very slightly underrate the number of possessions which end up inside the three-point line.
Good point. I agree. We should add in the possessions attributed to each. Now I really don't have the data to do that, since I don't have field goal attempt data (two pointers vs. three pointers) as of the data that this free throw data is collected. But it would shift the allocation slightly more towards two pointers.
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CrazyFromTheHeat
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PostPosted: Fri Feb 04, 2005 4:36 am Post subject: Reply with quote
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 7:16 am Post subject: Reply with quote
CrazyFromTheHeat wrote:
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
We have the free throw info for the whole league in this one case. But when I am wanting to compute two-point and three-point true shooting percentages for all 30 teams on a daily basis, we don't have the info (in an easily usable form) to do that.
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CrazyFromTheHeat
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PostPosted: Fri Feb 04, 2005 7:31 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
CrazyFromTheHeat wrote:
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
We have the free throw info for the whole league in this one case. But when I am wanting to compute two-point and three-point true shooting percentages for all 30 teams on a daily basis, we don't have the info (in an easily usable form) to do that.
Silly me! The way some of us come up with pages of stats around here (most notably you and Ed), I just assume that if I asked for Shaq's free throw percentage based on pre-game nap lengths, someone would trace it all the way back to LSU.
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PostPosted: Mon Jan 24, 2005 11:22 am Post subject: Reply with quote
Nikos: The data you want is at this Yahoo site.
MikeG: I found the error. In row 10398, there is the following record:
Code:
04-11-28 IND SEA harrison,david IND 1 1 Technical 2 9:45
That should read:
Code:
04-11-28 IND SEA harrison,david IND 1 2 Flagrant Type 1 2 9:45
Which means that David Harrison gets one more Flagrant 1 FTA (total = 2) and one fewer technical FTA (total = 0). I've updated the files at Yahoo to reflect the changes, or you can just change it on the copy you have now.
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CrazyFromTheHeat
Joined: 21 Jan 2005
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PostPosted: Mon Jan 24, 2005 9:26 pm Post subject: Reply with quote
Mike G wrote:
As to the wide range of BFTA/FTA, clearly there are 2 skills at work: drawing the foul, and finishing the shot. Iverson draws fouls and flings up prayers. Shaq tends to score with guys hanging on him.
I agree with this, except that you could say the same thing about other prominent players, and they don't show up on the "low" leaders board. Iverson's total number of attempts really stands out compared to the others on that list.
Mike G wrote:
Shaq might be at the top of the list if his FTA weren't diluted with hackashaq plays. No chance for a bonus shot there.
Good point. In his case, it might be more important to look at total number of BFTAs, where he is second to Stoudamire.
Mike G wrote:
There are quite a range of "ballhandling" fouls still in the mix (undifferentiated from "shooting" fouls.) I suspect these are more significant than differences in "finishing strength".
There's another great study right there - ability to draw fouls. It's all in the play logs, we just need the time and desire to count it. Of course, we could just ask Ed, and he'd probably have it for us tomorrow.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 10:18 pm Post subject: Reply with quote
To take out the effect of the ballhandling or Hack-a-Shaq fouls, all we need to do is change the denominator from all FTAs to Shooting FTAs, right? Let's see how that changes the leaderboard (I've also reduced minimum FTA to 50):
Code:
Player BFTA SFTA Pct
----------------------------
Jamison 21 98 21.4
JRose 17 81 21.0
Stoudamire 6 29 20.7
JSmith 13 63 20.6
Knight 9 45 20.0
Artest 6 30 20.0
JSmith 12 62 19.4
JuHoward 10 52 19.2
GWallace 15 79 19.0
Brand 35 185 18.9
Only 29 of Stoudamire's 71 free throws have been of the shooting variety.
Code:
Player BFTA SFTA Pct
----------------------------
Cardinal 0 50 0.0
Marshall 0 52 0.0
JrCollins 0 53 0.0
Lue 0 56 0.0
Hart 0 78 0.0
Cato 1 62 2.1
QRichardson 2 99 2.4
ADavis 1 54 2.7
Udrih 1 50 2.9
Ely 2 74 3.8
Shaq, incidentally, is at 15.8%, tied for 33rd with LeBron James ... and Jeff McInnis.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 10:30 pm Post subject: Reply with quote
We can also look at the ratio of shooting free throw attempts to total free throw attempts, which turns out to be pretty interesting:
Code:
Player SFTA FTA Pct
---------------------------
Drobnjak 66 72 91.7
ECurry 148 162 91.4
Mihm 125 137 91.2
Stoudemire 354 388 91.2
Mohammed 120 132 90.9
Ratliff 56 62 90.3
Sweetney 92 102 90.2
Ilgauskas 221 246 89.8
Fortson 165 185 89.2
LWright 57 65 87.7
This bears a suspicious resemblence to the original BFTA% list, for good reason -- it measured more the ability to get a lot of shooting fouls than to really convert fouls while shooting into makes.
Code:
Player SFTA FTA Pct
---------------------------
DJones 7 50 14.0
Atkins 29 86 33.7
Nash 35 102 34.3
Boykins 41 115 35.7
Hart 28 78 35.9
RMiller 27 70 38.6
Stoudamire 29 71 40.8
Posey 23 56 41.1
Ridnour 32 74 43.2
Van Exel 22 50 44.0
See, I did know something! Damon Jones isn't really that bad at converting BFTA opportunities; he's just only been fouled in the act of shooting only four times all season. (That's once every 329.5 minutes.)
Incidentally, there still must be some errors in the NBA's data. I'm not sure how exactly one shoots free throws on double technicals or offensive fouls. Not a big deal, since there's only a handful of them, but still the case.
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 10:45 pm Post subject: Reply with quote
admin wrote:
Incidentally, there still must be some errors in the NBA's data. I'm not sure how exactly one shoots free throws on double technicals or offensive fouls.
That's sweet of you to blame the NBA for the errors, but I assure you they're almost certainly mine. WRT to double-Ts, I'll comb the logs now to find the mistakes. Updates here.
However, the offensive fouls are real: if the team is in the penalty, the defensive team will shot FTs. Check out the action at the 0:19 mark of the 4th in this game.
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 10:59 pm Post subject: Reply with quote
Error found! Row 23350 reads:
Code:
05-01-04 PHX MIN outlaw,bo PHX 1 1 Double Technical 4 5:09
Should read:
Code:
05-01-04 PHX MIN outlaw,bo PHX 1 1 Shooting 4 5:09
That is the only Double-T. Files at Yahoo site updated to reflect changes. Further corrections gleefully accepted.
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Kevin Pelton
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PostPosted: Mon Jan 24, 2005 11:11 pm Post subject: Reply with quote
That's a mistake in the play-by-play. Offensive fouls are not team fouls, thus no shots can be attempted on them:
Quote:
PENALTIES: The offender is charged with a personal foul. The offended team is charged with a team foul if the illegal contact was caused by the defender. There is no team foul if there are personal fouls on one member of each team or the personal foul is against an offensive player.
http://www.nba.com/analysis/rules_12.ht ... rticleList
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Ed Küpfer
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PostPosted: Mon Jan 24, 2005 11:17 pm Post subject: Reply with quote
admin wrote:
That's a mistake in the play-by-play. Offensive fouls are not team fouls, thus no shots can be attempted on them
Ah well, what do I know. Luckily they only make up 8 of the FTAs in my sample.
In other news, I've uploaded a zip file containing all the logs I used to compile the data, if anyone wants to have a go. It's at the Yahoo site.
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HoopStudies
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PostPosted: Tue Jan 25, 2005 12:45 pm Post subject: Reply with quote
Ed Küpfer wrote:
In other news, I've uploaded a zip file containing all the logs I used to compile the data, if anyone wants to have a go. It's at the Yahoo site.
There are other errors with these logs, most pretty minor.
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
- They are inconsistent in their naming, somewhat understandably. If Cleveland is playing Seattle, Lebron James is listed as L. James to avoid confusion with J. James. But he's listed as just James in most games.
- I've noticed once that their labeling of what period it is is wrong.
Then, of course, there are times when the wrong person is credited with something. This is not correctable because it's also done in the official stats, but fortunately rare. Well, it's rare for things like assists and rebounds, but it still seems to me that a fair number of steals are credited to the person least responsible for it.
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Ed Küpfer
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PostPosted: Tue Jan 25, 2005 3:15 pm Post subject: Reply with quote
HoopStudies wrote:
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
Yeah, those are strange. This is one of the reasons mining PBP logs is such a chore for me. I wonder if the ESPN.com logs have this problem.
HoopStudies wrote:
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
Those aren't really a problem, unless you're logging the types of shots taken.
HoopStudies wrote:
- They are inconsistent in their naming, somewhat understandably. If Cleveland is playing Seattle, Lebron James is listed as L. James to avoid confusion with J. James. But he's listed as just James in most games.
The convention for NBA.com logs, if anyone is interested, is that if there is more than one player with the same last name on both teams playing, their surnames will be preceded by their first initial, a period, and a space. Otherwise, only their surnames will be shown.
What makes it difficult is some teams, during the course of the season, have two players with the same surname playing for them -- but not at the same time. For example, Steve Smith has played all season for the Bobcats. Until Dec 14, he would show up in the log as "Smith." After Dec 14, Theron Smith began playing for the team, and Steve's name was displayed under "S. Smith." At the end of the season, looking back at the games prior to December 14, you would have no idea which "Smith" it was to which the logs refered. You would have to look at the boxscores to see which one played. PITA.
HoopStudies wrote:
- I've noticed once that their labeling of what period it is is wrong.
Never seen that one. I'll keep an eye out.
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HoopStudies
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PostPosted: Tue Jan 25, 2005 4:08 pm Post subject: Reply with quote
Ed Küpfer wrote:
HoopStudies wrote:
- The score every so often goes berserk, going from 13-15 to 21-8 on one shot
Yeah, those are strange. This is one of the reasons mining PBP logs is such a chore for me. I wonder if the ESPN.com logs have this problem.
The QC on this one is straightforward, fortunately.
Ed Küpfer wrote:
HoopStudies wrote:
- Sometimes a player is listed with a score change and you know they must have made a shot but it isn't shown.
Those aren't really a problem, unless you're logging the types of shots taken.
Depends on what you're doing. It causes me QC problems.
Ed Küpfer wrote:
HoopStudies wrote:
- I've noticed once that their labeling of what period it is is wrong.
Never seen that one. I'll keep an eye out.
I remember a case where the 1st period was labeled as the 2nd period. I think they then had 2 fourth periods.
Sportsline and ESPN both have different info. ESPN has no info on shot type, but has distance. Sportsline has shot type but little of several other things. Sportsline has shot charts that are nice, too.
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CrazyFromTheHeat
Joined: 21 Jan 2005
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PostPosted: Tue Jan 25, 2005 8:48 pm Post subject: Reply with quote
admin wrote:
Damon Jones isn't really that bad at converting BFTA opportunities; he's just only been fouled in the act of shooting only four times all season. (That's once every 329.5 minutes.)
The trick with this is, there's a reason why DJ has only been fouled four times in the act of shooting all year. If DJ believed that he could get to the line regularly by driving to the basket regularly, then he would. He's not refusing to come inside the arc just because he's so good out there, he's doing it because he knows he has little chance of success in traffic.
A similar scenario would be saying that Shaq might be a good three-point shooter, we just don't know because he hasn't tried any. But we know that Shaq stays close to the basket because that's his best chance of success, and that if he started breaking the backboard with threes then he would diminish his value. DJ is the same way. He doesn't accumulate BFTAs because it's not what he does well, not because he isn't given an opportunity.
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Dan Rosenbaum
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PostPosted: Tue Feb 01, 2005 3:06 pm Post subject: Reply with quote
Ed Küpfer wrote:
Here's how the types of FTs break down:
Code:
FTAs
TYPE 1 2 3 TOTAL
Away from Play 35 4 0 39
Clear Path 28 0 0 28
Delay Technical 4 0 0 4
Double Technical 1 0 0 1
Elbow 0 4 0 4
Flagrant Type 1 0 77 0 77
Flagrant Type 2 0 12 0 12
Hanging Technical 12 0 0 12
Illegal Defense 341 0 0 341
Inbound 0 24 0 24
Loose Ball 3 1002 0 1005
Non Supported Technical 2 0 0 2
Offensive 0 8 0 8
Personal 8 6628 3 6639
Punching 2 0 0 2
Shooting 2473 18578 303 21354
Taunting Technical 6 0 0 6
Technical 446 0 0 446
TOTAL 3361 26337 306 30004
The FTAs that represent the end of a possession -- Shooting, Loose Ball, Away from Play, and Personal -- sum to 13259, or 44.2% of the total. Nice to have that FTA coefficent confirmed.
This is in response to a question that I got from DeanO through e-mail. When comparing teams, I compute true shooting percentage separately for two point attempts and three point attempts. But this raises a question. How do I allocate free throws between two point and three point attempts?
Two-point attempt free throws (possessions in parentheses)
Clear Path and Flagrant Fouls: 117 (0)
Shooting - 2 shot: 18,578 (9,289)
Shooting - 1 shot: 2,460 (0)
Total: 21,155 (9,289)
Three-point attempt free throws (possessions in parentheses)
Personal - 3 shot: 3 (1)
Shooting - 3 shot: 303 (101)
Shooting - 1 shot: 13 (0)
Total: 319 (102)
Unallocated (possessions in parentheses)
Away from Play - 1 shot: 35 (0)
Away from Play - 2 shots: 4 (2)
Technicals, Punching, and Illegal Defense: 814 (0)
Elbow: 4 (2)
Inbound: 24 (12)
Offensive: 8 (4)
Loose Ball - 1 shot: 3 (0)
Loose Ball - 2 shot: 1002 (501)
Personal - 1 shot: 2 (0)
Personal - 2 shots: 6,628 (3,314)
Total: 8,530 (3,835)
-- I tended to try to overallocate to two pointers, allocating all clear path and flagrant fouls to two point attempts.
-- I allocated 13 Shooting - 1 shot fouls to three pointers assuming that the odds of making a three-pointer when fouled was half that of making a two-pointer when fouled. This is only 13 free throws, so it is not a big deal whatever I do.
Now clearly there are some screwy categories here, and I am sure a handful of free throws are misallocated, but I think this is basically right. In essence, most free throws are fall in the two point attempt and unallocated categories. There are very few in the three point attempt category.
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
This would differ by team and would be different on offense and defense for a given team, but for an example, we can do this with the league averages.
As of January 31, about 80.6 percent of field goal attempts in 2004-05 were two point attempts, leaving 19.4 percent as two point attempts. Thus, this would result 6,878 of the unallocated free throws (and 3,092 of the unallocated possessions) being allocated to two pointers and 1,652 of the unallocated free throws (and 743 of the unallocated possessions) being allocated to three pointers.
Thus, after allocation here are the totals (with possessions in parentheses).
Two-point attempts: 28,033 (12,381)
Three-point attempts: 1,971 (845)
Note that this results in a possession multiplier of 0.442 for two point free throw attempts and 0.429 for three point free throw attempts.
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gabefarkas
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PostPosted: Tue Feb 01, 2005 5:08 pm Post subject: Reply with quote
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
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Dan Rosenbaum
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PostPosted: Tue Feb 01, 2005 5:15 pm Post subject: Reply with quote
gabefarkas wrote:
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
I think the consensus is that technicals count as zero possessions. In general, the possession of the ball does not change from one team to the other during a technical, flagrant, etc. Counting them as zero possessions is one of the reasons why free throw attempts count, on average, only 0.44 possessions.
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Ed Küpfer
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PostPosted: Tue Feb 01, 2005 5:33 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
Note that this results in a possession multiplier of 0.442 for two point free throw attempts and 0.429 for three point free throw attempts.
Nice. I've updated my web page so that team possessions calculations use a weighted average of those two coefficients.
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gabefarkas
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PostPosted: Wed Feb 02, 2005 6:56 am Post subject: Reply with quote
Dan Rosenbaum wrote:
gabefarkas wrote:
how do you guys handle FTA's where the team retains possession after the FT's? like technicals or flagrants and such?
is it two possessions, or one?
I think the consensus is that technicals count as zero possessions. In general, the possession of the ball does not change from one team to the other during a technical, flagrant, etc. Counting them as zero possessions is one of the reasons why free throw attempts count, on average, only 0.44 possessions.
so even if a team scores a point on a FTM, it's rolled into the next possession.
even with stuff like Floor%?
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CrazyFromTheHeat
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PostPosted: Thu Feb 03, 2005 10:33 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
Instead of the 75/25 split, wouldn't it be more accurate to split it along the lines of 21,155/319, or 98.5/1.5, the split between free throws from twos and threes? One thing we do know is that a very small percentage of free throws are associated with threes, so giving them 25 % of unallocated free throws seems very generous.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 12:26 am Post subject: Reply with quote
CrazyFromTheHeat wrote:
Dan Rosenbaum wrote:
My argument from here is that the unallocated free throws should be allocated to two pointers and three pointers by their proportions of overall shots. If two pointers are 75% of field goal attempts, then 75% of the unallocated free throws should be allocated to two pointers and 25% should be allocated to three pointers.
Instead of the 75/25 split, wouldn't it be more accurate to split it along the lines of 21,155/319, or 98.5/1.5, the split between free throws from twos and threes? One thing we do know is that a very small percentage of free throws are associated with threes, so giving them 25 % of unallocated free throws seems very generous.
I am only allocating the free throws that cannot be allocated to either two pointers or three pointers - mostly the non-shooting fouls. I am not allocating all free throws.
I guess I don't understand the point that a foul in the backcourt that leads to free throws or a technical free throw should almost always be allocated to two pointers. Many of those possessions end up in three point attempts. To me it makes more sense it just makes sense to allocate them in the proportion in which field goal attempts end up being two pointers or three pointers. Otherwise, I think we bias ourselves into thinking that two pointers are more efficient than they really are. My allocation method, in essence, does not allow these unallocated free throws to have an effect on the relative efficiency of two pointers vs. three pointers. That seems more reasonable to me.
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Kevin Pelton
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PostPosted: Fri Feb 04, 2005 12:51 am Post subject: Reply with quote
Dan - I'd add a very minor quibble: Shouldn't we add in the already allocated two-point FTA and three-point FTA along with two-point FGA and 3PA? The 75/25 would seem to very slightly underrate the number of possessions which end up inside the three-point line.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 1:24 am Post subject: Reply with quote
admin wrote:
Dan - I'd add a very minor quibble: Shouldn't we add in the already allocated two-point FTA and three-point FTA along with two-point FGA and 3PA? The 75/25 would seem to very slightly underrate the number of possessions which end up inside the three-point line.
Good point. I agree. We should add in the possessions attributed to each. Now I really don't have the data to do that, since I don't have field goal attempt data (two pointers vs. three pointers) as of the data that this free throw data is collected. But it would shift the allocation slightly more towards two pointers.
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CrazyFromTheHeat
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PostPosted: Fri Feb 04, 2005 4:36 am Post subject: Reply with quote
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
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Dan Rosenbaum
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PostPosted: Fri Feb 04, 2005 7:16 am Post subject: Reply with quote
CrazyFromTheHeat wrote:
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
We have the free throw info for the whole league in this one case. But when I am wanting to compute two-point and three-point true shooting percentages for all 30 teams on a daily basis, we don't have the info (in an easily usable form) to do that.
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CrazyFromTheHeat
Joined: 21 Jan 2005
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PostPosted: Fri Feb 04, 2005 7:31 pm Post subject: Reply with quote
Dan Rosenbaum wrote:
CrazyFromTheHeat wrote:
Dan - If the goal of your figures is to compute true shooting percentage separately for two point attempts and three point attempts, to isolate the two separate skills, then maybe the unallocated free throws should just be left out. I suppose that wouldn't chamge the result much, but seeing that you already have the info, and that the unallocated free throws by their definition have not come from a two-point or three-point play, it seems like there's no need to use them.
We have the free throw info for the whole league in this one case. But when I am wanting to compute two-point and three-point true shooting percentages for all 30 teams on a daily basis, we don't have the info (in an easily usable form) to do that.
Silly me! The way some of us come up with pages of stats around here (most notably you and Ed), I just assume that if I asked for Shaq's free throw percentage based on pre-game nap lengths, someone would trace it all the way back to LSU.
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