The job of evaluating player performance is a never ending
task for coaches. Larry Lindsay, an assistant coach at East Wake High School
in Zebulon, North Carolina has developed a tool to help coaches determine
how productive each player is when they are on the court.
Years ago, Coach Lindsay read about a formula that Bill
James developed for runs created in baseball. Mr. James used runs created
to determine how many runs a player was responsible for producing during
the season, based on his statistics. Coach Lindsay took this principle
and applied to basketball and developed a tool called Points Responsible
(PR for short). PR allowed him to take a state sheet and see how valuable
each player was statistically.
As he developed the formula for basketball, he had three
basic goals in mind. First, he wanted to emphasize all-around play. The
intention was to reward all-around play, not just points scored. The second
idea was to incorporate the idea of the four point play. That is, a turnover
cost not only in the two points you did not score but also the two points
it leads to on the other end. The third goal was the desire for PR total
to closely approximate the number of points scored by the team. How close
does this number correlate to a team’s actual points scored? On
almost every team that he used this statistical evaluation, the points
responsible number has been within 5% of the actual number of points that
the team scored.
The formula for points responsible is as follows:
Points + 2 (Rebounds
+ Assists + Steals + Charges Taken) + Blocked Shots – 2 (Missed
Field Goals + Turnovers) – Personal Fouls – Missed Free-Throws
You may wonder how he decided on the values for each statistical
categories. Rebounds and steals count as two points because they give
your team possession of the ball and allow you the opportunity to score
two points. A blocked shot may or may not give you possession, however,
it does create a miss for the other team. Missed shots and turnovers cause
you to lose possession of the ball. Since free-throws only count one point,
a missed free-throw only reduces your point total by one point. On the
average, a personal foul will cost you one point. This figure was reached
by looking at several NBA seasons and dividing the number of free-throws
made by the number of fouls. This also allows you to keep the formula
as simple as possible.
Table 1 shows some examples using the starting five from
a team coached by Lindsay. It includes all of the relevant statistics
for calculating PR. Notice that John, by far, was responsible for the
most points despite the fact that he was third in scoring. This occurred
because of John’s excellent rebounding and strong defensive play.
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Table 1- Team Statistics
Example
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| Name |
FG/A |
FT/A |
PTS |
REB |
ST |
BS |
CH |
AS |
TO |
PF |
PR |
| Ryan |
162-301 |
97-147 |
424 |
153 |
26 |
11 |
1 |
81 |
71 |
74 |
373 |
| John |
100-172 |
59-90 |
259 |
219 |
41 |
27 |
2 |
36 |
52 |
71 |
540 |
| Ray |
116-244 |
52-91 |
296 |
110 |
36 |
3 |
0 |
73 |
90 |
50 |
236 |
| Jimmy |
68-157 |
55-77 |
218 |
40 |
63 |
5 |
0 |
104 |
73 |
73 |
198 |
| Kevin |
59-148 |
31-71 |
147 |
110 |
13 |
18 |
0 |
14 |
43 |
50 |
63 |
Key: FG/A (Field Goals Made/Attempted)
FT/A (Free Throws Mades/Attempted) PTS (Points) REB (Rebounds) ST (Steals)
BS (Blocked Shots) CH (Charges or Offensive Fouls Taken) AS (Assists)
TO (Turnovers) PF (Personal Fouls) PR (Points Responsible For)
PR can be used in a number of different ways to help you
evaluate your team. First, you can find out the per game average of a
player. Simply divide the PR by games played. Second, if you want to look
at the efficiency of certain players, you can determine their PR rating
per thirty-two minutes. Multiply the players PR by thirty-two and divide
by minutes played. If you want to find out how a whole team of particular
players would perform, simply multiply the PR rating by 160 and divide
that number by minutes played.
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Table 2- Player
Efficiency
as determined by Points Responsible
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| Name |
PR |
PR/Game |
PR/32 |
PR/160 |
| Ryan |
373 |
13.3 |
15.6 |
77.9 |
| John |
540 |
19.3 |
24.3 |
121.5 |
| Ray |
236 |
8.4 |
10.2 |
51.1 |
| Jimmy |
198 |
7.1 |
9.1 |
45.4 |
| Kevin |
63 |
2.3 |
4.2 |
21.0 |
Key: PR (Points Responsible for)
PR/Game (Points Responsible for per game) PR/32 (Points Responsible for
per Minutes Played) PR/160 (Points Responsible for Groups of Players per
game)
While statistics are not perfect, PR does
help evaluate the overall performance of a player. It is particularly
useful in justifying the actions that you take when you hear complaints
from parents or players.
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