THE BOOK--Playing The Percentages In Baseball

Thursday, October 13, 2011

More interesting data for starters entering the 7th, 8th, and 9th innings…

I looked at starters who made it into the 7, 8, and 9 innings, from 07-10.  There obviously was overlap among the 3 buckets since any starter who made it into the 8th also made it into the 7th, etc.
For the three buckets, I looked at their performance in the previous innings versus their performance in that inning.

For example, I looked at all starters who pitched to at least 1 batter in the 7th.  I looked at their wOBA against in the previous 6 innings, which will obviously be low, otherwise they would not be allowed to pitch into the 7th on the average.  I then looked at their performance in the 7th to see if their good performance through 6 innings predicted a good or at least better than average performance in the 7th. I did that for the 8th and 9th innings as well.  I also computed the number of batters faced in the previous innings, as well as the distribution of scored going into the 7th, 8th, or 9th inning.

Here are the results.  I split it up into home and away pitching performance.

All starters at home

7th inning (N games=4333)

wOBA in previous 6 innings: .265
avg. # batters in previous 6: 22.2
Score distribution going into 7th
Tied: 15% Up 1: 14% Up 2: 11% Up 3 or more: 35%
Down 1 12% Down 2: 7% Down 3 or more: 5%
wOBA in 7th: .348
Overall wOBA of pitchers (for that year), i.e. true talent: .340
Overall wOBA of batters in the 7th inning: .332 (Avg. batter overall is .340)
Same side batters in the 7th inning: 43%

8th inning (N games=1385)

wOBA in previous 7 innings: .224
avg. # batters in previous 7: 24.8
Score distribution going into 8th
Tied: 13% Up 1: 12% Up 2: 12% Up 3 or more: 48%
Down 1 8% Down 2: 5% Down 3 or more: 3%
wOBA in 8: .333
Overall wOBA of pitchers (for that year), i.e. true talent: .335
Overall wOBA of batters in the 8th inning: .332 (Avg. batter overall is .340)
Same side batters in the 8th inning: 41%

9th inning (N games=345)

wOBA in previous 8 innings: .185
avg. # batters in previous 8: 27.3
Score distribution going into 9th
Tied: 6% Up 1: 9% Up 2: 11% Up 3 or more: 68%
Down 1 3% Down 2: 2% Down 3 or more: 1%
wOBA in 9th: .300
Overall wOBA of pitchers (for that year), i.e. true talent: .333
Overall wOBA of batters in the 9th inning: .338 (Avg. batter overall is .340)
Same side batters in the 9th inning: 44%

All starters on the road

7th inning (N games=3583)

wOBA in previous 6 innings: .267
avg. # batters in previous 6: 22.4
Score distribution going into 7th
Tied: 14% Up 1: 14% Up 2: 12% Up 3 or more: 38%
Down 1 11% Down 2: 6% Down 3 or more: 5%
wOBA in 7th: .346
Overall wOBA of pitchers (for that year), i.e. true talent: .346
Overall wOBA of batters in the 7th inning: .338 (Avg. batter overall is .340)
Same side batters in the 7th inning: 40%

8th inning (N games=1118)

wOBA in previous 7 innings: .226
avg. # batters in previous 7: 25.0
Score distribution going into 8th
Tied: 12% Up 1: 12% Up 2: 11% Up 3 or more: 50%
Down 1 9% Down 2: 3% Down 3 or more: 3%
wOBA in 8th: .355
Overall wOBA of pitchers (for that year), i.e. true talent: .346
Overall wOBA of batters in the 8th inning: .338 (Avg. batter overall is .340)
Same side batters in the 8th inning: 41%

9th inning (N games=257)

wOBA in previous 8 innings: .181
avg. # batters in previous 8: 27.3
Score distribution going into 9th
Tied: 9% Up 1: 8% Up 2: 8% Up 3 or more: 75%
Down 1 0% Down 2: 0% Down 3 or more: 0%
wOBA in 9th: .371
Overall wOBA of pitchers (for that year), i.e. true talent: .346
Overall wOBA of batters in the 9 inning: .343 (Avg. batter overall is .340)
Same side batters in the 9th inning: 41%

How about the same data for elite starters?  This time I defined an elite starter as a top 20 starter (both leagues combined) based on my projections going into each year.

Elite starters at home

7th inning (N games=620)

wOBA in previous 6 innings: .260
avg. # batters in previous 6: 22.0
Score distribution going into 7th
Tied: 17% Up 1: 14% Up 2: 12% Up 3 or more: 36%
Down 1 12% Down 2: 6% Down 3 or more: 3%
wOBA in 7th: .303
Overall wOBA of pitchers (for that year), i.e. true talent: .315
Overall wOBA of batters in the 7th inning: .337 (Avg. batter overall is .340)
Same side batters in the 7th inning: 41%

8th inning (N games=284)

wOBA in previous 7 innings: .231
avg. # batters in previous 7: 24.8
Score distribution going into 8th
Tied: 14% Up 1: 14% Up 2: 13% Up 3 or more: 45%
Down 1 8% Down 2: 4% Down 3 or more: 1%
wOBA in 8th: .312
Overall wOBA of pitchers (for that year), i.e. true talent: .315
Overall wOBA of batters in the 8th inning: .338 (Avg. batter overall is .340)
Same side batters in the 8th inning: 40%

9th inning (N games=95)

wOBA in previous 8 innings: .202
avg. # batters in previous 8: 27.5
Score distribution going into 9th
Tied: 11% Up 1: 12% Up 2: 14% Up 3 or more: 57%
Down 1 5% Down 2: 1% Down 3 or more: 1%
wOBA in 9th: .327
Overall wOBA of pitchers (for that year), i.e. true talent: .315
Overall wOBA of batters in the 9th inning: .344 (Avg. batter overall is .340)
Same side batters in the 9th inning: 39%

Elite starters on the road

7th inning (N games=560)

wOBA in previous 6 innings: .268
avg. # batters in previous 6: 22.4
Score distribution going into 7th
Tied: 16% Up 1: 14% Up 2: 11% Up 3 or more: 37%
Down 1 11% Down 2: 6% Down 3 or more: 5%
wOBA in 7th: .311
Overall wOBA of pitchers (for that year), i.e. true talent: .316
Overall wOBA of batters in the 7 inning: .336 (Avg. batter overall is .340)
Same side batters in the 7th inning: 40%

8th inning (N games=218)

wOBA in previous 7 innings: .229
avg. # batters in previous 7: 25.1
Score distribution going into 8th
Tied: 13% Up 1: 16% Up 2: 8% Up 3 or more: 50%
Down 1 8% Down 2: 4% Down 3 or more: 2%
wOBA in 8th: .323
Overall wOBA of pitchers (for that year), i.e. true talent: .316
Overall wOBA of batters in the 8th inning: .337 (Avg. batter overall is .340)
Same side batters in the 8th inning: 40%

9th inning (N games=63)

wOBA in previous 8 innings: .180
avg. # batters in previous 8: 27.3
Score distribution going into 9th
Tied: 8% Up 1: 14% Up 2: 10% Up 3 or more: 68%
Down 1 0% Down 2: 0% Down 3 or more: 0%
wOBA in 9th: .338
Overall wOBA of pitchers (for that year), i.e. true talent: .316
Overall wOBA of batters in the 9 inning: .343 (Avg. batter overall is .340)
Same side batters in the 9th inning: 40%

Looking at all the data, there does not appear to be much evidence that when pitchers last into at least the 7th or later innings, facing the order for the 3 time or more, that they perform any better than expected, after adjusting for the batters they face, including platoon issues. 

Even the elite starters had a wOBA against of around .329 in the 9th inning, worse than their overall numbers (.316) and far worse than a typical closer.

I would love it if someone could duplicate my work as I am not nearly 100% certain that I did not make any mistakes.