In The Book, Tango, Lichtman, and Dolphin studied player performances pinch hitting and DHing. Their conclusions were as follows:

*The Book*: players hit somewhat worse as pinch hitters than when they are playing a regular fielding position.

Doing the same thing for designated hitters (DHs), I find a weighted average offensive winning percentage as a DH of 0.511 and as position players (again, excluding PH and PR appearances) of 0.523 for the players who have done both in a single season. This works out to a DH “penalty” of 0.012. Overall, 58.9% of these players (3,451) had a worse offensive winning percentage as designated hitters than as position players, very similar to the PH penalty that I found above. This differs somewhat from*The Book*, which found a much smaller "DH penalty" than "PH penalty".

Out of curiosity, I did the same thing for pinch runners, comparing baserunning winning percentages for pinch runners as pinch runners versus when they reached base as a batter. Pinch runners have a weighted average baserunning winning percentage of 0.494 as pinch runners versus 0.517 for the same players otherwise for the 16,150 players who did both in a single season. This works out to a PR penalty of 0.023. Overall, 54.1% of these players (8,731) had a worse baserunning winning percentage as pinch runners.

Finally, I looked at players who earned player decisions as both a DH and a pinch hitter in the same season. There were a total of 5,599 such players. The weighted average of their winning percentage as a DH was 0.509 vs. 0.454 as a pinch hitter, implying a "PH penalty" of 0.055.

In calculating positional averages (which serve as the baseline from which I calculate positional replacement levels), I use the actual average winning percentage for these positions. Hence, these positional penalties are implicitly adjusted for in the calculation of these positional averages and replacement levels.

“A player is significantly less effective as a pinch hitter than he is as a starter…. Players also lose effectiveness when being used as a designated hitter; the DH penalty is about half that of the PH penalty.” (Tango, Lichtman, and Dolphin,I decided to undertake a similar analysis using Player Won-Lost records. Across all of the seasons for which I have estimated Player won-lost records, 32,622 players amassed offensive Player decisions as a pinch hitter as well as while playing a fielding position (i.e., excluding DH and pinch-running appearances as well as PH appearances) . Using the harmonic mean of the players' offensive Player decisions as a PH and as a position player for weights, the weighted average winning percentage of these players as pinch hitters was 0.475. The weighted average offensive winning percentage for the same players when playing the field was 0.484. So, on average, a player’s offensive winning percentage is 0.009 less as a pinch-hitter than as a non-PH. Overall, 59.0% of these players (19,232) had a worse offensive winning percentage as pinch hitters than as position players. So, I generally find the same result asThe Book: Playing the Percentages in Baseball, page 113)

Doing the same thing for designated hitters (DHs), I find a weighted average offensive winning percentage as a DH of 0.511 and as position players (again, excluding PH and PR appearances) of 0.523 for the players who have done both in a single season. This works out to a DH “penalty” of 0.012. Overall, 58.9% of these players (3,451) had a worse offensive winning percentage as designated hitters than as position players, very similar to the PH penalty that I found above. This differs somewhat from

Out of curiosity, I did the same thing for pinch runners, comparing baserunning winning percentages for pinch runners as pinch runners versus when they reached base as a batter. Pinch runners have a weighted average baserunning winning percentage of 0.494 as pinch runners versus 0.517 for the same players otherwise for the 16,150 players who did both in a single season. This works out to a PR penalty of 0.023. Overall, 54.1% of these players (8,731) had a worse baserunning winning percentage as pinch runners.

Finally, I looked at players who earned player decisions as both a DH and a pinch hitter in the same season. There were a total of 5,599 such players. The weighted average of their winning percentage as a DH was 0.509 vs. 0.454 as a pinch hitter, implying a "PH penalty" of 0.055.

In calculating positional averages (which serve as the baseline from which I calculate positional replacement levels), I use the actual average winning percentage for these positions. Hence, these positional penalties are implicitly adjusted for in the calculation of these positional averages and replacement levels.