April 21, 2003

WWII Difficulty

How Much Does Wartime Affect Quality of Play?

by Clay Davenport

Sixty years ago, America was at war.

That one was very different, and one of those differences was the way baseball reacted. This time around, no one from the major leagues was going to take any part in the fighting, and certainly won't now that it's winding down. It is unlikely that anyone from the minor leagues will take any part (if there are any minor league players who are in the Guard and have been called up, I haven't been able to find any mention of it.)

There are a number of ways to look at how much difference the military service of ballplayers made on the quality of the league at a given time. One of the simpler ways is to compare the aggregate statistics of players coming into the major leagues to the aggregate of the players who were going out. For instance, this line...

                Leaving  Entering
                PA       EQA     PA      EQA
AL 1935-36      3687    .225    4852    .240

...shows that the players who were in the American League in 1935, but not in the major leagues at all in 1936, combined for 3687 plate appearances and hit for a .225 EQA, adjusted for park and league. Big surprise--the players who are getting replaced are below-average hitters (an average major leaguer, for any given season, has an EQA of .260). The players who were in the AL in 1936, but did not play in the majors in 1935, combined for 4852 plate appearances and a .240 EQA. The newcomers played more often and hit better than the ones they replaced.

That was a typical result prior to the war:

                Leaving  Entering
                PA       EQA     PA      EQA
AL 1935-36      3687    .225    4852    .240
AL 1936-37      4350    .231    5941    .241
AL 1937-38      3924    .225    5849    .245
AL 1938-39      3484    .226    7714    .254
AL 1939-40      3475    .225    3977    .236
AL 1940-41      1883    .225    5418    .243

Average         3467    .226    5418    .243

NL 1935-36      5313    .244    5701    .251
NL 1936-37      6607    .232    7520    .243
NL 1937-38      4304    .238    5168    .259
NL 1938-39      4747    .252    6988    .240
NL 1939-40      4265    .240    5613    .235
NL 1940-41      5005    .240    4860    .248

Average         5040    .241    5975    .245

The replacements in the AL always played more, and hit better, than the ones they replaced. The NL story is a little more mixed, as there are a couple of years where the replacements were worse than the ones who left, and one where they had a few more PAs. The NL in the pre-war years appears to have been more aggressive about replacing below-average players, as their de facto replacement level was about 15 points of EQA higher than in the AL--that works out to about .021 runs per out. Consequently, more players were rotated out in the NL (since the bar to stay was higher, more players fell under it). The AL was losing about 7.3% of its plate appearances, and 5.3% of its total equivalent run production, in a typical year, while annual NL losses were 10.8% and 8.8%. Think of that as the baseline attrition level going into war.

Pearl Harbor was bombed during the 1941-42 off-season. While a few players were called to service in 1941 in anticipation of a war (notably Hank Greenberg), there was no general call-up until after Pearl. Even then, it took time build up the forces, and so many players at least played part of the 1942 season before getting called--which means they wouldn't show up in these stats I'm running, since the player had to be completely absent in the adjacent year. You can see some effect in 1942, though:

AL 1941-42      8536    .259    6777    .246
NL 1941-42      7364    .246    6657    .250

The number of plate appearances lost between '41 and '42 is more than double the baseline attrition rate in the AL, and the quality of the players lost was basically league average; the AL lost between 17 and 18% of their PAs and EQR from the year before. The replacements put up typical replacement numbers, perhaps playing a little more often, but they were nowhere near as good as the ones they replaced. The story in the NL was less extreme. Losses were higher than in previous years, but only by about 50%, and the quality of the players lost was not appreciably different than normal. Their replacements actually did a little better.

The story changed by the time the season began in April 1943. Between April 1942 and April 1943 the U.S. Army alone (i.e., not counting the Navy or other service branches) increased in size from 2.7 million men to 6.8 million. More than 300,000 men joined the army every month from July '42 to April '43, mostly via the draft, with inductions peaking at over 500,000 in October alone (see http://carlisle-www.army.mil/cgi-bin/usamhi/DL/showdoc.pl?docnum=347, pages 57-58). The playing time lost between '42 and '43 reflects that buildup:

AL 1942-43      15347   .266    12636   .256
NL 1942-43      12834   .261    10311   .248

The AL lost 33% of its plate appearances, and 34% of its equivalent runs, as the departing cohort was above average in hitting. Ted Williams and Joe DiMaggio were the two biggest stars to go, but they were far from alone. NL losses once again were not quite as severe, with "only" 28% of their PA and EQR departing. The difference between how well the departing regulars and their replacements hit is deceiving, because in each case we are measuring against a league average of .260--even though the 1943 leagues have taken a huge qualitative hit. I'll get back to this later, but just keep in mind for now that a .260 in 1943 is probably not as good as a .260 from 1942.

The rest of this article is restricted to Baseball Prospectus Subscribers. Not a subscriber? Click here for more information on Baseball Prospectus subscriptions or use the buttons to the right to subscribe and get access to the best baseball content on the web.

Cancel anytime. That's a 33% savings over the monthly price! That's a 33% savings over the monthly price! Already a subscriber? Click here and use the blue login bar to log in.