By default, all stats on this site exclude garbage time and possessions at the end of quarters that are highly likely to end up in a heave. When we use stats to evaluate players and teams, we are trying to do so in the context of a normal game. Garbage time and projected heave possessions are not reflective of a normal game, and so these stats are filtered out.
Garbage Timeclick to show/hide
Cleaning the Glass uses a definition of garbage time that is as objective as possible and generally matches up with most people's perception of when garbage time starts: when the game is out of hand, both teams have subbed out most of their starters, and the game never gets close again.
The Gritty Details
The exact definition CTG uses is: the game has to be in the 4th quarter, the score differential has to be >= 25 for minutes 12-9, >= 20 for minutes 9-6, and >= 10 for the remainder of the quarter. Additionally, there have to be two or fewer starters on the floor combined between the two teams.
Importantly, the game can never go back to being non-garbage time, or this clock resets. For example, if it's a 30 point game to start the 4th quarter, but one team comes back and pulls the game within 8, that comeback is not counted as garbage time. If the leading team regains control and expands the lead back out, garbage time would start when the score went back above 10.
This might not capture all of what we'd call garbage time, but it seeems important to err on the side of caution and not mistakenly filter out any game time that we would not consider garbage time.
Projected Heave Possessionsclick to show/hide
At the end of a quarter, teams will sometimes get a possession where the clock is so low when it starts that they don't have time to run a normal play. They generally rush the ball up the court and fling a shot up, or otherwise might not even get a shot off. These are possessions by the definition, but they are qualitatitively different than a normal possession and thus can skew stats. They are possessions where, at the start, it seems highly likely the team will end up with a heave shot. Cleaning the Glass filters these out by default as well, so as not to penalize players and teams for a low percentage shot during this type of possession.
The Gritty Details
CTG defines these possessions as those that start with 4 or fewer seconds on the game clock at the end of one of the first three quarters.