PER takes minutes played into account, though. If not, it seems like a statistical measurement that is slanted to give starters a higher number. I still await Hollinger's explanation. I'll throw in that Batum, Bayless, and Cunningham are all near or above 15 in PER. I'd like to know how that is possible given their low amount of minutes.
Efficiency is by definition "Per something", not total. That's why people with small minutes played can be over 15. Again, look at the math - you tart with "unadjusted PER" which is:
uPER = (1 / MP) *
[ 3P
+ (2/3) * AST
+ (2 - factor * (team_AST / team_FG)) * FG
+ (FT *0.5 * (1 + (1 - (team_AST / team_FG)) + (2/3) * (team_AST / team_FG)))
- VOP * TOV
- VOP * DRB% * (FGA - FG)
- VOP * 0.44 * (0.44 + (0.56 * DRB%)) * (FTA - FT)
+ VOP * (1 - DRB%) * (TRB - ORB)
+ VOP * DRB% * ORB
+ VOP * STL
+ VOP * DRB% * BLK
- PF * ((lg_FT / lg_PF) - 0.44 * (lg_FTA / lg_PF) * VOP) ]
And notice the first element - (1 / MP) * (which is another way of saying - take all the things we can measure that come below and divide them by the minutes played).
The next step is to adjust it to pace:
aPER = (pace adjustment) * uPER
and finally, normalize it a league average of 15
PER = aPER * (15 / lg_aPER)
Of course, lg_aPER is the same calculation as aPer only for all the players in the league based on the number of minutes they are playing.
So - basically, you calculate the individual efficiency, divide it by the composite league wide efficiency and multiple by 15 to normalize across seasons. The numbers are "per minute" as I said, because lg_aPER will also start the same calculation by dividing by minutes played - (1/MP)*