[BostonCard]

I ran across an analysis that uses some NBA statistics mixed with some physical analysis (it was a follow up to this May 2015 article).  It isn't a research paper, so it wasn't peer reviewed and may have errors.  He begins talking about drag and altitude about 2/3 way down.  But, talking about sea level, he says "The drag force should only alter the path of a free throw by about 6 inches, which is probably at the limit of the SportVU system's precision."   I'm not quite sure why 6 inches wouldn't be extremely visible.  If he means that the shot would be 6" shorter due to drag, then that would be immediately obvious except that the players compensate for it.  If he means that the highest point of a free throw's  path would be 6" higher after compensation, I think that would be pretty obvious.

I imagine that SportVU, which is based on cameras around the stadium, digitizes each action so that for any shot you can calculate position (in three dimensions) and a vector of velocity (angle and speed).  From that, you should be able to calculate the effect of forces, including drag, on the ball.  I am a bit surprised that the error would be as much as six inches, but of course it is not zero, and there almost certainly is some imprecision in the digitization process.

SportVU is mostly used by teams as an analytics to try to determine optimum plays to run (such as which player should be shooting and from where) and probably doesn't need better than 6 inch resolution, but the cameras are all high-speed, high-resolution cameras.

Fun fact about SportVU: "SportVU was created in 2005 by Israeli scientists, Gal Oz and Miky Tamir,[6] who had a background in missile tracking and advanced optical recognition.[7][8] They had previously used some of that same science to track soccer matches in Israel."
(from the wiki)



BC

[BostonCard]

I ran across an analysis that uses some NBA statistics mixed with some physical analysis (it was a follow up to this May 2015 article).  It isn't a research paper, so it wasn't peer reviewed and may have errors.  He begins talking about drag and altitude about 2/3 way down.  But, talking about sea level, he says "The drag force should only alter the path of a free throw by about 6 inches, which is probably at the limit of the SportVU system's precision."   I'm not quite sure why 6 inches wouldn't be extremely visible.  If he means that the shot would be 6" shorter due to drag, then that would be immediately obvious except that the players compensate for it.  If he means that the highest point of a free throw's  path would be 6" higher after compensation, I think that would be pretty obvious.

I imagine that SportVU, which is based on cameras around the stadium, digitizes each action so that for any shot you can calculate position (in three dimensions) and a vector of velocity (angle and speed).  From that, you should be able to calculate the effect of forces, including drag, on the ball.  I am a bit surprised that the error would be as much as six inches, but of course it is not zero, and there almost certainly is some imprecision in the digitization process.

SportVU is mostly used by teams as an analytics to try to determine optimum plays to run (such as which player should be shooting and from where) and probably doesn't need better than 6 inch resolution, but the cameras are all high-speed, high-resolution cameras.

Fun fact about SportVU: "SportVU was created in 2005 by Israeli scientists, Gal Oz and Miky Tamir,[6] who had a background in missile tracking and advanced optical recognition.[7][8] They had previously used some of that same science to track soccer matches in Israel."
(from the wiki)



BC