Player stats Calculations

How are the statistics calculated?

AT BAT (AB)

In our sport, this is Plate appearance minus Bases on Balls. In fastpitch and baseball the definition is a little more complicated. We don’t collect it directly as it can be inferred from plate appearances (PA) and walks/bases on balls (BB), but it is used in some of the calculations (AVG, OBP and SLG).

What is a hit?

A Hit: (denoted by H), is credited to a batter when the batter safely reaches first base after hitting the ball into fair territory, without the benefit of an error or a fielder’s choice.  Examples:

  • If the batter is thrown out at first (before she reaches 1st ) that is not a hit
  • If the batter got past first and was on his way to 2nd or 3rd before he was tagged out that is a hit and he would be credited with a 1B or 2B hit for that
  • Being caught out is not a hit (even if the batter had already rounded first when the catch was made)
  • If the batter got safely to first but, when she batted, the fielding team put someone else out on a force out that is a Fielder’s Choice and is not a hit
  • Walking to first (a BB) is not a hit

Runners batted in (RBI)

This is the number of runners who came in (to score a run) that can be credited to the batter.  So, if the batter is caught out, but a runner still makes it in to home as a consequence of the at bat, the batter is credited one RBI.  For RBIs on home runs: don’t forget to count the batter him/herself So, with bases loaded, a home run brings 4 RBIs.

BATTING AVERAGE (avg)

The player’s batting average is simply the number of Hits divided by At Bats. We have established that At Bat = PA-BB, so we use

AVG = H / (PA – BB)

AVG is expressed as 3 decimal places (e.g. .300). In this example the batter would be getting on base nearly a third of the time (not counting walks) and this player would be said to be “batting three hundred”.

ON-BASE PERCENTAGE (OBP)

(Sometimes referred to as on-base average, OBA) OBP is a measure of how frequently a batter reaches base. It is the ratio of the batter’s times-on-base (TOB) (the sum of hits and walks) to their number of plate appearances (PA).

OBP = (H + BB) / PA

This is often depicted as: OBP = ( H + BB ) / (AB + BB)

SLUGGING PERCENTAGE (SLG)

Slugging percentage is a measure of the batting productivity of a hitter. It is calculated as total bases divided by at bats, through the following formula, where AB is the number of at bats for a given player, and 1B, 2B, 3B, and HR are the number of singles, doubles, triples, and home runs, respectively:

SLG = ( 1B + (2 x 2B) + (3 x 3B) + (4 x HR) ) / AB

So, for us (as we do not directly count 1B hits or ‘At bat’):

SLG = (  (H – 2B – 3B – HR) + (2 x 2B) + (3 x 3B) + (4 x HR) ) / (PA – BB)