By Roger Weber
In baseball's beginning, the
only offensive stat kept track of was runs. The player who scored the most runs was selected as the best player. In the late
1800s hits started being monitored. These were a better way of telling a player's ability, but still this was improved upon
with the invention of batting averages. Different types of hits were kept track of but well into the mid-1900s batting average,
and home runs to an extent, was the only statistic many fans kept track of.
With the dawn of the computer
and statistics age in baseball new stats have been invented that supposedly are better measures of run producing ability better
than the older more popular statistics. Perhaps the most respected of those is Bill James' statistic, "runs created.." It
is based on the idea that producing runs includes getting runners on and then getting them over the rest of the bases and
into home. The basic formula is "On base percentage times total bases."
The title of this segment is
somewhat of a misnomer. "Runs created" clearly is an accurate and probably the best basic way of telling a player's run production.
But it is difficult to calculate mentally if the only statistics available are the individual ones of on base percentage and
total bases.
Here is a chart of how other
statistics correlate with "runs created."
Statistic |
R^2 |
OPS |
.96 |
Total bases |
.86 |
Slugging average |
.80 |
On base percentage |
.61 |
Batting average |
.49 |
Runs scored |
.46 |
RBI |
.45 |
Home runs |
.44 |
Walks |
.20 |
Doubles |
.1 |
Plate Appearances |
.09 |
"OPS" (On base percentage plus
slugging average) has almost a perfect correlation with runs created, and is easier to calculate because it requires only
simple addition. It correlates so well that it is basically interchangeable. In fact, "OPS" multiplied by 85 (or even 100
with a slightly raised scale for runs created) is a quite close estimator of James' famous statistic.
And total bases, one of the
components of "runs created," correlates quite closely, too. With total bases, it isn't enough to call them interchangeable
but if you're just looking for a quick estimation of a player's ability to create runs, using total bases is a good one to
use, as is slugging average.
"Runs created" is the best
measure of a player's hitting ability, and is easy to use once calculated. You can add stolen base runs and even "DER," another
of James' creations, defensive runs, to get a total number of runs a player contributes to his team's success. But as far
as estimating purely hitting ability to produce runs, "runs created" can be substituted with a few other statistics and the
results don't change much.