Ever played hoops with somebody who wouldn't stop shooting at every chance even though he was missing more shots than the CDC during flu season? That affliction isn't limited to your lunchtime pickup game at the local Y. Plenty of NBA players suffer from the same problem, putting a serious damper on their teams' offensive productivity.
We know this to be true merely by observing Antoine Walker or the post-injury Chris Webber, for example. When it comes to shooting, each has become infamous for emphasizing quantity rather than quality. But are they the NBA's two worst offenders, or are some other players gunning just as egregiously? And if so, how much are these players costing their teams with all those missed shots?
To figure this out, we need a way to measure which players are doing the most damage to their teams with their wayward shooting. This measure should reflect two attributes: 1) shooting badly and 2) shooting frequently. First, we need to define what we mean by "shooting badly." In this case, we're not just referring to a low shooting percentage. After all, some players make enough 3-pointers or get to the line often enough that they're much more effective than their shooting percentages suggest. A few, such as Chauncey Billups, manage to do both, making them much better than their percentage (in this case 42.8) would lead us to believe.
Thus, rather than using a player's nominal shooting percentage, the way to measure shooting effectiveness is to use what I call a player's True Shooting Percentage (TS%) adjusted for 3-pointers and free throws. That way, we can properly measure players who get an extra point for their long jumpers or extra free throws from their drives to the basket.