I haven’t posted in a while, but I have a good excuse. I’ve been assembling a database of play-by-plays from the last five seasons. This will make it much easier to investigate many areas of the game. It’s not completely finished yet, but already there’s a lot of interesting stuff that I can pull from the database. For example, I can quickly calculate that in the four seasons from 2003-04 to 2006-07 (I’m missing a few games, but I have over 99% of games from that time period), there were 14,216 hook shots taken. 45.5% of those shots were made, 54% of those makes were assisted, and 4% of all hook shots were blocked. But that’s not what I really want to examine in this post. Instead I’m going to look at shot location data.
During all NBA games, diligent game charters sit courtside and mark the location of every shot taken on the court down to the square foot. I believe this is done by using a stylus on a touchscreen monitor with a replica of the court on it. This is the source of the shot charts you can see after a game on ESPN.com or CBS Sportsline, and of the compiled shot charts of NBA.com’s Hot Spots (which I discussed in my first post). With the play-by-play database I’ve constructed it’s possible to look at this shot location data in a number of ways.
First, below is a picture showing where players shoot from. Again it’s based on data from 03-04 to 06-07. The court dimensions are to scale, and each one-foot by one-foot square on the court is color-coded based on the number of field goal attempts from that spot. The color scale runs from blue (few FGA) to yellow (some FGA) to red (many FGA). Obviously the charted locations aren’t 100% accurate, but there are still some very interesting patterns that emerge.
Where Players Take Shots - FGA by Location:
Next, below is a picture showing how well players shoot from different locations. The color-coding is based on the field goal percentage from each spot. Because some one-foot by one-foot squares had a very low number of shot attempts, I grouped the data into three-foot by three-foot squares to reduce the noise (so the shading for a single 1×1 ft square actually represents the FG% in the 3×3 ft square that it’s in the center of). Again, the color scale runs from blue (low FG%) to yellow (average FG%) to red (high FG%).
Where Players Make Shots - FG% by Location:
Finally, this last picture looks at what percent of the made shots from various locations were assisted. For this one I used the basic one-foot by one-foot squares, with the color indicating the percent of the made shots from that spot that were assisted. The color scale is the same - blue (low percentage of makes assisted) to yellow (medium percentage makes assisted) to red (high percentage of makes assisted).
Which Shots are Assisted - Assists/FGM by Location:
Obviously a lot could be said about all of these pictures, but I’ll leave it at that for now. I mainly just wanted to give a preview of some of the kinds of things I’ll be looking at in future posts using data from this new play-by-play database.
UPDATE: I’ve added a few more charts in a new post.