True Shooting% - question

HeatRing2012 · Post #1 » by **HeatRing2012** » Thu Dec 19, 2013 2:38 pm

hi there

so I've stumbled upon the TS% formular and wondered where that "0.44" coefficient is coming from... anyone know about it?

TS%
True Shooting Percentage; the formula is PTS / (2 * TSA). True shooting percentage is a measure of shooting efficiency that takes into account field goals, 3-point field goals, and free throws.

TSA
True Shooting Attempts; the formula is FGA + 0.44 * FTA.

Post #2 » by **bondom34** » Thu Dec 19, 2013 3:06 pm

HeatRing2012 wrote:hi there

so I've stumbled upon the TS% formular and wondered where that "0.44" coefficient is coming from... anyone know about it?

TS%
True Shooting Percentage; the formula is PTS / (2 * TSA). True shooting percentage is a measure of shooting efficiency that takes into account field goals, 3-point field goals, and free throws.

TSA
True Shooting Attempts; the formula is FGA + 0.44 * FTA.

The .44 is a constant for an estimate of how many FTs end a possession. Not all do, since they could be the first of 2 or 3. It's just an estimate from old play by play data, but the best/most accurate way to calculate would be to actually watch or have play by play and just use the amount from that.

HeatRing2012 · Post #3 » by **HeatRing2012** » Thu Dec 19, 2013 3:13 pm

I noticed that as well...

especially since we have a trend to more three pointers in the NBA, hence free throws should be lower.

Keller61 · Post #4 » by **Keller61** » Fri Jan 17, 2014 12:55 am

It's pretty easy to find exact TSA using the basketball-reference.com event finder and searching for a player's FTA. For example, using LeBron's 2012-13 season:

http://www.basketball-reference.com/play-index/plus/event_finder.cgi?request=1&player_id=jamesle01&event_code=fta&year_id=2013&is_playoffs=N&team_id=&opp_id=&quarter=&time_remain_quarter=&margin=

Just count up the number of flagrant, technical, and-1, and 3rd FTs, subtract that from the total FTA, and divide by 2 to get the number of TSA from FTs. LeBron's exact TS% comes out to be .643, instead of the reported .640.

Of course, I think it's debatable whether the points from technical FTs should even be included in a scoring efficiency stat, since those FTs don't use possessions and come from the other team making a mistake, not from an actual scoring attempt.