Title: Do Pitchers Try Harder for Their 20th Win?
1Do Pitchers Try Harder for Their 20th Win?
- Phil Birnbaum
- www.philbirnbaum.com
- July 31, 2009
2Do pitchers try harder for their 20th win?
- Bill James, "The Targeting Phenomenon"
- Historically, there are more players who finished
with one win than with two - More with 2 than with 3. More than 3 than with 4
- Every number is harder to hit than the previous,
except - There are more pitchers with 20 wins than 19.
3Do pitchers try harder for their 20th win?
- Why?
- Bill James "players WANT to wind up the season
hitting .250, rather than in the .240s. They
tend to make it happen." - But HOW do they make it happen?
4Do pitchers try harder for their 20th win?
- Clutch pitching?
- Do players actually try harder when they can win
their 20th? - That would mean they wouldn't be trying their
hardest in other games - Not a nice theory
5Season win totals, 1940-2007
6Maybe it should look more like this
7Why?
- Five possible factors I could think of
- There could be more
- Take them one at a time
8Factor 1 extra starts
- Maybe pitchers are given an extra start late in
the season to try to get to 20 - In that case, those pitchers would have a larger
proportion of starts in September
9Percentage of starts in September for pitchers
who eventually finish with
- 16 wins 17.53
- 17 wins 17.77
- 18 wins 18.36
- 19 wins 18.49
- 20 wins 18.47
- 21 wins 18.15
- 22 wins 18.18
- -- A little bulge at 19-20, maybe 0.25
10Percentage of starts in September
- The 19-20 win pitchers had 9229 starts
- An extra 0.25 means an extra 23 starts
- Maybe 10 wins
- By this analysis
- 19-win pitchers, circumstances created 10 fewer
(-10) of them - 20-win pitchers, 10 extra (10)
11Factor 2 relief appearances
- Maybe 19-win pitchers got a relief appearance to
try to reach 20 - Check the historical record
- Big metaphorical wet kiss to Retrosheet
12Factor 2 relief appearances
- Eventual 20-game winners with relief wins
- 1951 Early Wynn wins 18th
- 1951 Mike Garcia wins 19th
- 1956 Billy Hoeft wins 20th
- 1957 Jim Bunning wins 20th
- 1966 Chris Short wins 20th
- 1991 John Smiley gets 19th
- 1997 Randy Johnson gets 20th
- 7 extra wins
-
13Factor 2 relief appearances
- Eventual 19-game winners with relief wins 3
- Eventual 20-game winners with relief wins 7
(previous slide) - Eventual 21-game winners with relief wins 6
- Take these numbers at face value, since they're
exact historically
14Factor 3 clutch pitching
- The obvious question did they just pitch better
with 19 wins, with the 20th on the line? - How did the pitchers actually perform with
various numbers of wins?
15Team RA and win pct. for pitchers
- 17 wins 3.72 RA, .658
- 18 wins 3.54 RA, .652
- 19 wins 3.54 RA, .655
- 20 wins 3.62 RA, .615
- 21 wins 3.53 RA, .676
- 22 wins 3.34 RA, .774
- (Note RA is for team, not just the starter wins
are at the time of the start, not at end of
season) - Only a tiny bit of difference maybe .08 RA?
- I feel better pitchers are still team players
16Team RA and win pct. for pitchers
- Move the 20-win group from 3.62 to 3.54
- Difference 39 runs over 490 starts 4 wins
- Four 20-win pitchers "should have" moved to 21
wins - So four extra 20s, four fewer 21s
17But wait!
- The 20-win group's RA was only a bit higher than
you'd expect - But their winning percentage was much, much too
low! - 18 wins 3.54 RA, .652
- 19 wins 3.54 RA, .655
- 20 wins 3.62 RA, .615
- How come? Run support.
18Factor 4 run support
- 19 wins 3.54 RA, .655, 4.45 RS
- 20 wins 3.54 RA, .615, 4.05 RS
- 21 wins 3.62 RA, .676, 4.46 RS
- Holy crap!
- After achieving their 20th win, pitchers' batters
let them down in their tries for 21 - A huge 0.4 run per game shortfall!
19Factor 4 run support
- There were 490 starts by pitchers with exactly 20
wins - 0.4 runs per game is 196 runs
- That's 20 wins! Maybe 15 of those wins would have
gone to the starter - So 15 pitchers got "stuck" at 20 wins instead of
moving to 21 - That's an extra 15 twenty-game winners, and 15
fewer twenty-one-game winners.
20Factor 5 more decisions
- Maybe when a pitcher is going for 20, the manager
will leave him in longer - Looks like it! Wins per start, 17 to 22 wins
- .484, .496, .521, .463, .505, .554
- Suppose they should have been .505. That's 11
extra wins. - So we have an extra 11 twenty-game winners, and
11 fewer nineteen-game winners.
21Totalling it up
Starts Relief Clutch Support Decisions Total
19 10 3 11 18
20 10 7 4 15 11 47
21 6 4 15 13
22One last adjustment
- However some of these pluses and minuses need to
"move up" a category - Example a manager gives his starter an extra
relief appearance he wins his 20th. But five
days later, he wins his 21st. - We think that should be a move between 19 and 20,
but it really wound up as a move between 20 and
21 - I'm arbitrarily going to adjust
- 19s from 18 to 16
- 20s from 47 to 37
- 21s from 13 to -7
23Final score
- Final total
- 19 game winners 16
- 20 game winners 37
- 21 game winners 7
- If we back all these effects out of the original
data, there should be no more bulge at 20
24Not perfect, but not bad
25Summary
- By this estimate, there were 37 "extra" 20-game
winners compared to expected. - 10 because of extra starts in September
- 7 because of relief appearances in September
- 3 because 20-game pitchers didn't pitch well
enough to get to 21 - 11 because 20-game pitchers got such bad run
support that they couldn't get to 21 - 6 because managers left the pitchers in longer in
hopes they'd get their 20th that day.
26Summary
- So is it because pitchers want it to happen?
- No it's mostly because managers want it to
happen. - Broken down
- 23 manager decisions
- 3 pitchers pitching worse when already at 20
- 11 run support luck.
27Reference
- Bill James, "The Targeting Phenomenon," The Bill
James Gold Mine 2008, p. 67