Average Possession Length

Last updated 2 months ago

Tempo or pace shows how a team prefers to play. A team's style.

Do they play up-tempo? Do they like to slow it down? Do they play man-to-man defense? Or zone?

A lot of these questions can be answered calculating a team's average possession length.

Average possession length is a closer look at a team's pace. It's a new metric, and KenPom introduces it in this article.

`APL = a team's seconds on offense and defense`

What does this mean and why is it important?

This metric tells you on average, how long a team has the ball. It adds to the character of how a team plays.

This calculation isn't adjusted. It measures the entire possession meaning offensive rebounds count.

This is important because it can test assumptions about a team.

KenPom provides the following example:

If a coach insists he likes to run, his offensive APL is your personal lie-detector test.

If a coach likes to go up-tempo, but his average possession length is 20 seconds, that's not entirely true.

It's often assumed the team that controls the pace wins the game or gains an advantage. This also isn't always true. A team controls the pace often times because it's winning and not the other way around.

In more research, KenPom found that the offense is responsible for 86% of the variance in predicting a team's average possession length.

This means the offense often dictates the pace of the game. It's not meant to be taken as a fact. This should be examined on a game-by-game basis.

Think of APL as a decoration or ornament to a team's style.

Examples

In the 2017-18 season, Virginia ranked 351st in offensive APL at 20.9 seconds. Virginia's average offensive possession against opponents last about 21 seconds.

Virginia plays patient and seeks the best offensive shot. The Cavaliers also rarely turn the ball over, ranking 5th in offensive turnover rate.

This style caters to a low offensive APL.

In contrast, Auburn ranked 17th in defensive APL at 16.4 seconds in the 2017-18 season. On average, the Tigers' defensive possessions lasted about 16 seconds.

Auburn's opponents shot an above average percentage, ranking 111th in effective field goal percentage. Opponents rarely turned over the ball and seldom got to the free throw line.

This all describes a style of high defensive APL.

3-point field goal attempt percentage

This is a simple stat to measure the amount of 3-point shots a team attempts.

`3PA% = 3-point attempts / Field goal attempts`

For example, the 2017-2018 Villanova team had a a 3PA% of 47.5. This was good for 12th in the country.

This means about 48% of the shots Villanova took, were from 3-point range.

Other Style Components

Several other statistics contribute to a team's style. These are covered in the Team Stats section.