Defensive (actually fielding) Efficiency

Baseball is an odd game.  The offense does not possess the ball.  The defense cannot score.  The best defense is a strike out.


Measuring individual defense is unlike measuring individual offense mainly because the offense is not required to hit the ball to an individual defender.  I am very skeptical about the various measurements such as Nick Swisher somehow appearing to be a good defender.  What am I to believe: the defensive stats or my lying eyes? Or is it the lying defensive stats?


Defense is best measured on a team level.  Baseball defense has two components: pitching and fielding.  Most people make fielding synonymous with defense.  This is clearly incorrect.


The common sense measurement of team fielding is the percent of batted balls converted into outs.  There is a measurement for this with the unfortunate description of Defensive Efficiency.  Clearly it should be called Fielding Efficiency as it removes both strike outs and home runs (I assume only those hit over fences) and includes both hits and batters who reach base on errors.


Seventy percent seems to be a good number, i.e., a team converts 70% of fielding opportunities into outs, not including uncaught foul flies.


baseball-reference.com calls it DeffEff.  Here's the link for the 1934 AL.  If you sort DeffEff you will see that the Yankees led with .703 (70.3%).  They also led each season after through 1939 and won the WS in 1936, 1937, 1938, 1939.  So did the 1927 Yankees.  The 1961 Yankees were second to Baltimore.  The 1998 Yankees led and won 114 games.  So maybe there's some real value here.


The 1933 Yankees were last in fielding efficiency (DeffEff): 68.2%. The 1932 Yanks won the WS but were only fifth with 69%, slightly above the AL average (68.8%).  The DeffEff number is about the same but the rank dropped from 5 to 8.  What was the difference between the 1932 and 1933 Yankees?  Beats me.  The starters were all the same (1933 ages shown):

C Bill Dickey 26
1B Lou Gehrig 30
2B Tony Lazzeri 29
SS Frankie Crosetti 22
3B Joe Sewell 34
OF Earle Combs 34
OF Babe Ruth 38
OF Ben Chapman 24


Crosetti made 43 errors in 1933.  Lazzeri 25.  Sewell 13.  Their error totals in 1932: 29, 17, 9.  Lyn Larry also played 91 games in the 1932 infield and made 25 errors.  According to the DeffEff definition in baseball-reference.com, 71% of errors result in a batter reaching base as opposed to advancing on the bases.


The 1932 Yanks made 190 errors, 1933 164.  Errors do not seem to be the reason that the 1933 Yankees were last in fielding efficiency.


The 1934 Yanks made 160 errors and led AL in DeffEff: 70.3%.  Crosetti had a wopping 39 errors, followed by rookie Red Rolfe (19) who had played only one game previously (in 1931) and shared third base with 31 year old Jack Saltzgaver (12).  Lazzeri made 18 errors and Chapman 13.

Hits/Innings DeffEff rank:
1932 1,425 1,408 5th
1933 1,426 1,354.66 last
1934 1,349 1,382.66 first


Only in 1934 did the Yanks allow fewer hits than innings pitched.

Errors DeffEff rank error rank:
1932 190 5th 5th fewest errors
1933 164 last 4th fewest errors
1934 160 first second fewest errors


H/9 rank:
1932 first; won WS
1933 second to Washington (first in DeffEff), which won 99 games to Yanks 91
1934 first; Detroit (4th in DeffEff) won 101 games, Yanks second with 94


What to make of DeffEff?  Don't know.