# WIS User Interview - girt25 Topic

True shooting % = pts / (2(fga + .44fta))
1/30/2013 10:07 PM
interesting, do you know the history behind that? or how the .44 was decided upon? i am 99% sure ive seen that formula a number of times, but never knew where it came from. i always wanted to come up with my own formula, but i was always lazy and just used pts/fga (weighting down mentally for high fta players).
1/30/2013 10:42 PM
I don't know why .44 is there but I have a feeling it is a fitted number based on the # of +1's (fg made and foul) and fts from technical fouls, divided by all free throws. If there are no +1s or technical fouls, then 2 ft = 1 offensive shot, which means the multiplier for ft would be .5
1/31/2013 12:25 AM
I have a couple of questions regarding the ts%.

1) How early in a season can you use it? Is it like RPI in that you need at least 8 games to make it relevant or is it based on having scored XX points?

2) Again like RPI, does it become more accurate later in the season?

3) Can you use previous season data to predict future season effectiveness?

4) How does IQ impact the ts%? Should a coach expect the ts% to increase as IQ improves?

5) After calculating ts%, should a coach still adjust distribution based on opponent matchups, type of defense, etc?
1/31/2013 1:38 AM
I use both TS% and EFG%.  When I update the numbers every few games depending on my free time.
The numbers don't really start carrying weight though until you have a sufficiently high number of attempts for that player across 2pt, 3pt, and FT.  That point can happen at different times of the season depending on the player's usage, the teams tempo, etc.  Generally, I don't put much value in the numbers until the player has 100+ points.  I also balance it against what I would expect a player of that caliber to produce based upon his ratings.  The numbers get more accurate as the season goes on and the sample size gets bigger.  There is a argument to be made, however, that even at the end of the season, the sample size is too small and the variation in opposing talent from game to game too large to ever have an accurate number, but I tend to think they provide decent value.  On my best teams, I tend to schedule in the top 20 SoS and try to play pretty consistent levels of talent so the numbers have more value because the quality of defender is pretty consistent game to game.

Although I understand the point about FTs, it seems the more my players drive, the more offensive fouls they commit which offsets some of the benefits of drawing fouls on the opposing team.
1/31/2013 9:29 AM
On ts%, are 2 pt. and 3 pt. shots considered equal?
1/31/2013 10:15 AM
Not exactly.  TS% weighs all FGA attempts with FTA related to total points scored.    As a FGA from 3pt carries more potential value than from 2pt, it carries more built-in weight in the formula.
For a look at a number of advanced metrics, see:
1/31/2013 11:26 AM
Posted by tianyi7886 on 1/31/2013 12:25:00 AM (view original):
I don't know why .44 is there but I have a feeling it is a fitted number based on the # of +1's (fg made and foul) and fts from technical fouls, divided by all free throws. If there are no +1s or technical fouls, then 2 ft = 1 offensive shot, which means the multiplier for ft would be .5
Its basically that, plus the fact that there is lost potential in a lot of FT if it is a 1 and 1.   Miss the first one, then you lost the chance to score another point so 1 FTA is not equal to 0.5 a 2pt attempt because if you don't make the first FT of a 1-1, the box score will show 0-1 on FT but really, you should think of it as 0-2 because when you first went to the line, you had the potential to score 2 points but only ended up with 1 attempt
1/31/2013 11:30 AM
Always obtain more knowledge about the game from the interviews, well done, Girt.   Plus, you get your mind blown from the thread itself ... interesting stuff.
1/31/2013 11:44 AM
Posted by dukenilnil on 1/31/2013 9:29:00 AM (view original):
I use both TS% and EFG%.  When I update the numbers every few games depending on my free time.
The numbers don't really start carrying weight though until you have a sufficiently high number of attempts for that player across 2pt, 3pt, and FT.  That point can happen at different times of the season depending on the player's usage, the teams tempo, etc.  Generally, I don't put much value in the numbers until the player has 100+ points.  I also balance it against what I would expect a player of that caliber to produce based upon his ratings.  The numbers get more accurate as the season goes on and the sample size gets bigger.  There is a argument to be made, however, that even at the end of the season, the sample size is too small and the variation in opposing talent from game to game too large to ever have an accurate number, but I tend to think they provide decent value.  On my best teams, I tend to schedule in the top 20 SoS and try to play pretty consistent levels of talent so the numbers have more value because the quality of defender is pretty consistent game to game.

Although I understand the point about FTs, it seems the more my players drive, the more offensive fouls they commit which offsets some of the benefits of drawing fouls on the opposing team.
On your last point, while that's true, doesn't it figure into the turnover numbers? So that's still only two things you really need to look for to judge offensive efficiency (TS%, turnovers)
1/31/2013 11:48 AM
Weena
I have a couple of questions regarding the ts%.

1) How early in a season can you use it? Is it like RPI in that you need at least 8 games to make it relevant or is it based on having scored XX points?
2) Again like RPI, does it become more accurate later in the season?
Valid point -- you definitely can't rely on it too early. In this sense, it's no different from looking at field goal percentage -- anyone can shoot well or poorly in a small sample size. There's no magic number of games or shots -- the larger the sample size, the more relevant the number is. I will generally take a peek at it after non-con and possibly make some adjustments, but even 10 games is a pretty small sample size. I will take a closer look after the regular season and before the postseason starts, and make tweaks accordingly.

3) Can you use previous season data to predict future season effectiveness?
Kinda/sorta. First, situations and team composition change. Second, even a full season isn't necessarily enough to be totally reliable. Perhaps most importantly, at their core I would rely on ratings and iq as the main factor in predicting success. I view this other stuff as ways of finetuning.

4) How does IQ impact the ts%? Should a coach expect the ts% to increase as IQ improves?
IQ certainly has an impact on offensive efficiency. All else being equal, ts% will increase as IQ improves. That said, it's also likely that all else won't be equal -- namely, that distro will increase as a player matures, and that will impact efficiency.

5) After calculating ts%, should a coach still adjust distribution based on opponent matchups, type of defense, etc?
Yes, I certainly do. I definitely do not set me distro according to ts% or any other metric I might use. Again, I would view that kind of statistical analysis as another tool in your bag of tricks, but definitely not the only tool.

Happy that the interview could spark a good discussion like this.
1/31/2013 3:36 PM
Great interview girt!
1/31/2013 3:40 PM
I'm just disappointed that you didn't give a shout out to the great swamphawk. How quickly we forget.
2/3/2013 11:57 AM
I'm a little disappointed I wasn't invited to the sports roundtable... Other than that, great interview ;)
2/4/2013 8:12 PM
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WIS User Interview - girt25 Topic