Secondary average, or SecA, is a
baseball statistic
Baseball statistics play an important role in evaluating the progress of a player or team.
Since the flow of a baseball game has natural breaks to it, and normally players act individually rather than performing in clusters, the sport lends itsel ...
that measures the sum of extra bases gained on hits, walks, and stolen bases (less times caught stealing) depicted per at bat.
[James, Bill. ''The Bill James Historical Baseball Abstract''. New York: Villard Books, 1988.] Created by
Bill James, it is a
sabermetric
Sabermetrics, or originally SABRmetrics, is the empirical analysis of baseball, especially baseball statistics that measure in-game activity. Sabermetricians collect and summarize the relevant data from this in-game activity to answer specific ques ...
measurement of hitting performance that seeks to evaluate the number of bases a player gained independent of
batting average
Batting average is a statistic in cricket, baseball, and softball that measures the performance of batters. The development of the baseball statistic was influenced by the cricket statistic.
Cricket
In cricket, a player's batting average is ...
. Unlike batting average, which is a simple ratio of base
hit
Hit means to strike someone or something.
Hit or HIT may also refer to:
Arts, entertainment and media Fictional entities
* Hit, a fictional character from '' Dragon Ball Super''
* Homicide International Trust, or HIT, a fictional organization ...
s to
at bats
In baseball, an at bat (AB) or time at bat is a batter's turn batting against a pitcher. An at bat is different from a plate appearance. A batter is credited with a plate appearance regardless of what happens during their turn at bat, but a batt ...
, secondary average accounts for power (
extra base hit
In baseball, an extra-base hit (EB, EBH or XBH), also known as a long hit, is any base hit on which the batter is able to advance past first base without the benefit of a fielder either committing an error or opting to make a throw to retire ano ...
s), plate discipline (
walks), and speed (
stolen bases minus times caught stealing).
["Career Leaders for Secondary Average.]
''Baseball Almanac''
Baseball-Almanac. 2013. Web. 11 Nov. 2013. Secondary averages have a higher
variance
In probability theory and statistics, variance is the expectation of the squared deviation of a random variable from its population mean or sample mean. Variance is a measure of dispersion, meaning it is a measure of how far a set of numbe ...
than batting averages.
Formula
The formula to calculate secondary average is:
:
where
*''BB'' =
bases on balls
*''TB'' =
Total bases
In baseball statistics, total bases is the number of bases a player gains with hits. It is a weighted sum with values of 1 for a single, 2 for a double, 3 for a triple and 4 for a home run. For example, three singles is three total bases, whil ...
*''H'' =
Hits
*''SB'' =
Stolen bases
*''CS'' =
Caught stealing
*''AB'' =
At bats
In baseball, an at bat (AB) or time at bat is a batter's turn batting against a pitcher. An at bat is different from a plate appearance. A batter is credited with a plate appearance regardless of what happens during their turn at bat, but a batt ...
The resulting number rounded to the thousandth place is a player's secondary average. Variations to the formula exist, with some statisticians not counting caught stealing while others multiply caught stealing to increase its significance/negative effects.
Relation to batting average
Although they share a limited
correlation, overall league averages for secondary average are inclined to correspond with league batting averages, which allows for a viable reference point for secondary average in comparison to batting average.
A player can possess a low batting average yet still be a valuable offensive contributor if he has a high secondary average.
[James, Bill. ''The Baseball Book 1990''. New York: Villard Books, 1990.] However, a low secondary average is not necessarily an indicator of a poor hitter.
Ichiro Suzuki is an example of a hitter who relies on batting average for most of his offensive production.
[Grochowski, John]
"Baseball by the Numbers: Adam Dunn Shows His Value in Secondary Average."
''Chicago Sun-Times''. Sun-Times Media, LLC, 20 Aug. 2012. Web. 11 Nov. 2013. Furthermore, batting average and secondary average are not mutually exclusive; a player can have a high batting average as well as a high secondary average. The table below shows the leaders in both batting average and secondary average for the 2013 season (bold indicates leader in both categories).
Benefits for player evaluation
Secondary average operates under the principle that batting average is an incomplete indicator of a hitter's ability since batting average does not account for power, plate discipline, and speed. According to Scott Gray (working with Bill James), "Secondary average is a much better indicator of offensive ability than batting average".
Since secondary average evaluates a player's offensive contribution independent of batting average, it can identify players who have low batting averages yet are still productive offensively. For example, in 1990, Bill James identified
Eric Davis as the most productive batter with a career average below .275; in spite of his low batting average, Davis had a career secondary average of .504, which was the highest of any active player at the time.
Batting average was not a great indicator of his true offensive value; secondary average was able to demonstrate his value more effectively.
Adam Dunn is an example of a recent player who has a low batting average but an excellent secondary average, resulting from his high walk totals and power numbers.
Notably, during each season in a 5-year stretch in which he hit 40+ home runs, he hit more homers than doubles. Although Adam Dunn only has a career .238 batting average,'
"Adam Dunn"
''Baseball-Reference.com''. Sports Reference LLC, n.d. Web. 11 Nov. 2013. he has a career .456 secondary average, ranking him 12th all-time.
References
{{Baseball statistics
Batting statistics
Bill James