Statistical Glossary

Total Average

A ratio of the bases a player accumulates for his team and the outs he costs his team. Total average is a Thomas Boswell statistic included in a delightful book, How Life Imitates the World Series (see Bibliography).

TA = (TB+HBP+BB+SB)/(AB-H+CS+GIDP)

Using the above formula, league total averages for 1992 were .627 without the DH and .664 with the DH. If a player has a TA over 1.000, that's very good.

Runs Contributed

An estimate of the number of runs contributed to a team's offense by each player above the number contributed by an average player in the league. A Pete Palmer statistic.

Like runs created, runs contributed is an attempt to measure the overall offensive contribution of a player in terms of the only thing that ultimately counts, number of runs. If you divide runs contributed by the runs required per win (approximately 10, see Runs Required Per Win), you have the wins contributed by this player's offensive performance above the league average.

Pete actually calls runs contributed "Batting Runs" to distinguish it from Defensive Runs, Stolen Base Runs, and Pitching Runs, all "Linear Weights," and all measures of contributions to the team stated in terms of runs. In the formula below, we use the historical average 0.25 for the league factor (it can vary from approximately 0.24 to 0.26 from one year to the next). This means that the sum of runs contributed for all players is not precisely zero, as it would be if the league factor were adjusted to overall league performance. In comparing players from a single season, their relative performance is not changed by using this approximation.

RCON = (.46)S+ (.80)D+ (1.02)T+ (1.40)HR+ (.33)(BB+HP)+ (.30)SB- (.60)CS- (.25)(AB-H)

Bigs: An average player would contribute approximately zero (0) runs above average. An average outfielder might contribute 20 runs in 400 plate appearances above the average player in the league. On the other hand, a good shortstop might be expected to contribute no runs above the average player in the league. Clearly, outfielders are expected to be better offensively than shortstops.

Players having great seasons contribute 40 to 70 runs; very poor seasons are in the range -40 to -20. Only players who play a lot can have a very high or low season total, since the absolute number is dependent on number of games played.

Runs Created

An estimate of the number of runs that a player would produce based on his offensive statistics. Runs created is an attempt to measure total offensive contribution in terms of runs. Divided by the runs required per win (in professional baseball, approximately 10), runs created becomes the total wins created by this player's offensive performance. A Bill James statistic.

RC = ((H+BB+HBP-CS-GIDP) * (TB+0.26*(BB+HBP-IBB) + 0.52*(SB+SH+SF)))/(AB+BB+HBP+SH+SF)

[Note: The formula shown here is the modern formula in current use by sabermetricians. Bill James created many variations of the basic formula to adjust for available data and other factors in bygone eras. For a complete exposition on the evolution of the Runs Created formula, see the Bill James Historical Abstract, Section II, Part III.]

Bigs: RC typically ranges from 0 to 120 in a 162-game season. Only players who play a lot can have a very high season total, since the number is dependent on total stats. For a team, runs created is a projected estimate of the runs the team should have scored given its number of hits (by type), walks, stolen bases, and times caught stealing. Comparing team runs created to actual runs scored gives an indication of other factors at work, factors that effect the efficiency of a team's offense. For instance, high efficiency -- consistently scoring more runs than projected -- could be explained by good clutch hitting, good baserunning, good managing, or good luck (or maybe cheating). The more consistent the two figures, the less luck is probably involved.

Runs Created Per Game

Runs created is an accumulation stat; the more a player bats, the more runs he creates (assuming he make some positive contribution). Converting runs created into runs created per game provides an indication of how valuable this player is to have in the lineup. RC/G is somewhat like ERA is for pitchers; it recasts the offensive contribution of the player in the context of a nine inning (in this case, 27 out) game. To calculate RC/G, multiply RC by 27 and divide by the number of outs the player is responsible for (OM), thus:

RC/G = 27*RC/OM

[Note: The formula shown here is the modern formula in current use by sabermetricians. Since data is available to account for all outs made, it is appropriate to use 27 outs as the context. In earlier periods, data on some kinds of outs (GIDP and CS are examples) are incomplete or unavailable. Consequently, applying the formula to other eras requires use of 25.5 or 26 outs per game. For a complete exposition on the application of the Runs Created formula to this RC/G calculation, see the Bill James Historical Abstract, Section II, Part IV.]

One way to look at RC/G is to imagine a lineup with the same player batting in every spot. A team made up of nine 1992 model Barry Bonds, for example, would be expected to score 11.34 runs per game on average. (Bonds had 147 runs created in 1992.)

Opponent's Stolen Base Average

The average number of opposition stolen bases per game in games started by each catcher or pitcher. A measure of their effectiveness at stopping the running game. A Bill James statistic.

For catchers: OSBA = (9*OSB/INN).
For pitchers: OSBA = (9*OSB/IP).

Bigs: for catchers and pitchers, about 0.5 to 1.3 stolen bases allowed per game (less is better)

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