Late Night Sabermetrics
I was messing around with some leverage index stuff after thinking about why Jason Kendall would ever, ever hit in a save situation, and this is what came out of my brain tonight. Just wondering if this is something worth continuing with. Notes were entered in note pad, so we'll see how neat they are here.
AT WHAT LEVERAGE INDEX DO YOU PULL A DEFENSIVELY MINDED PLAYER IN THE BOTTOM OF THE 9TH INNING EVERY TIME?
- WHEN DO YOU PLAY A BETTER FIELDER OVER THE BETTER HITTER
-+50 R/150G FIELDING
- +.31 R/G => +.0711 R/PA AT 4.34 PA/G (average)
- AT 1 LI
-.113 wOBA = -.0713 R/PA
-.195 wOBA = .0000 R/PA
-.277 wOBA = +.0713 R/PA
-SO A .082 DIFFERENCE IN WOBA ROUGHLY EQUALS A +50 R/150 DIFFERENCE IN FIELDING
-SCALE IS LINEAR
-+25 R/150 = .039 WOBA POINTS
-+10 R/150 = .0156 WOBA POINTS
-ETC.
-WE ASSUME THAT THE REGULAR FIELDER WILL HAVE A 1.00 pLI, BUT HOW MUCH BETTER DOES THE BENCH HITTER HAVE TO
BE TO DEMAND A PINCH HIT, BASED ON LI?
- CONSIDER THAT THE HITTER RECEIVES A ROUGHLY -.025 IMPACT TO HIS wOBA IN A PH ROLE
- 4.9% OF GAMES GO TO EXTRA INNINGS - SO THEN THE PINCH HITTER OR SOME DEFENSIVE REPLACEMENT MUST TAKE
THE FIELD
- THEN RV(B-9) = LI*{[PH(wOBA)-.025) - STARTER(wOBA)]/1.15}
+ xinLI*{.049*[(DREPLACE(DEF)/150/4.34)-STARTER(DEF)/150/4.34)]}
[Note by jhmoore, RV(B-9) is run value in the bottom of the 9th]
-SPECIFIC EXAMPLE
-JASON KENDALL vs. MIKE RIVERA (OR ANGEL SALOME)
-JASON KENDALL: wOBA (2008): .293
-MIKE RIVERA: wOBA (2008): .309
-DIFFERENCE: .016
-THE BREWERS ORGANIZATION SEEMS TO ASSUME ROUGHLY 15 RUN DIFFERENCE AT CATCHER (10 BY TZONE)
-15 R/150 = .246 wOBA POINTS
-IF THE ORGANIZATIONS ASSUMPTION IS TRUE (DEBATABLE), KENDALL SHOULD BE EVERYDAY CATCHER
-BUT WHEN SHOULD KENDALL BE PINCH HIT FOR
-KAPLER wOBA FOR BREWERS 2008 - .362
-KAPLER(wOBA) - .025 = .337
-RV(B-9) = LI*{[KAPLER(wOBA)-.025-KENDALL(wOBA)]/1.15}
+ xinLI*{.049*(RIVERA(DEF)/150/4.34)-KENDALL(DEF)/150/4.34}
= LI*[.337-.293]/1.15 + 2.50*.049(-.0926)
= LI*[.0383] - .0113
-RV(B-9) = LI*[.0383] - .0113, UNDER THE ASSUMPTION THAT EXTRA INNING LI WORKS OUT TO ~2.50
-BREAKEVEN POINT
- 0 = LI*[.0383] - .0113
- LI*[.0383] = .0113
- LI = .0113/.0383
- LI = .295
-SO ACCORDING TO THIS, THE ONLY SITUATION IN THE BOTTOM OF THE NINTH WHERE KENDALL SHOULD BAT
WITH A KAPLER-QUALITY PHAVAILABLE IS WHEN LI < .295,
OR 2 OUTS, BASES EMPTY 2 OUTS, NOBODY ON
-BUT IN THIS SITUATION, THE CHANCE OF EXTRA INNINGS IS MUCH MUCH LOWER THAN 4.9% (RE ~= .1),
SO THE CORRECT MOVE IS STILL TO PINCH HIT
0 recs |
7 comments
Comments
Why is the LI of the fielder assumed to be 1?
If the LI varies significantly from 1 for the PH analysis, can’t it be assumed that the field LI will be significantly different from 1?
It’s probably difficult, but how about considering the opportunity cost of PH “Kapler” for “Kendal” instead of potentially saving him for a different PH at-bat?
Is there a theoretically acceptable way to adapt this line of thought to the top of the ninth and think about 1/2 inning of the replacement fielder for certain, plus the option of extras? Also, you could probably calculate the exact probability of extra innings given each game state. And what about the possibility of the replacement “fielder” eventually coming to bat?
Beyond the Boxscore // Calling BJ Upton lazy is lazy.
by Sky Kalkman on May 10, 2009 9:54 PM EDT reply actions 0 recs
That was supposed to be pLI for the fielder hitting.
The LI for fielding in extras is accounted for in the “xinLI” field. I decided to try and overestimate and pick 2.50 as that LI, because I couldn’t find extra inning LI tables last night.
I certainly do plan on trying to extend this sort of thought to the top of the 9th. It should be possible but I think the equation will get a little bit more complicated. As far as opportunity cost of the pinch hitter goes, I suppose we need to establish some sort of chaining for a bench similar to that with a bullpen. The idea that I had involves the fact that the team OBP for the other 8 hitters in the lineup will be the variable that determines the likelihood of the spot being pinch hit for coming up in the 9th, 10th, 11th, etc. and how to really flesh this out. I think this could get really complicated but I actually kind of like that.
I’ll be working on this more this week and especially after this week is over (it’s finals week here) I’ll hopefully see if this is something that’s worth actually working on. I really like this sort of thing where the game can be almost completely reduced to numbers in a purely theoretical setting (and that’s why I’m a pure math major).
---
Juuuust a bit outside!!
http://www.rightfieldbleachers.com
by Jack Moore on May 10, 2009 11:18 PM EDT up reply actions 0 recs
Sounds like applied math to me ;)
Modeling, statistics, state machines…
Beyond the Boxscore // Calling BJ Upton lazy is lazy.
by Sky Kalkman on May 10, 2009 11:44 PM EDT up reply actions 0 recs
Splitting hairs, pfft
-HOW TO MODIFY THE EQUATION
-LET'S LOOK AT THE EQUATION IN SIMPLER TERMS
- RV(B-9) = 9th Hitting Value + OC of PH +10th fielding value + 10th hitting value + 11th fielding value + ... + 20th hitting value
- 9th hitting value = LI*{[(PH(wOBA)-.025) - STARTER(wOBA)]/1.15
- OPPORTUNITY COST OF PINCH HITTING
- THIS ONE IS SLIGHTLY MORE COMPLICATED
- IF WE ASSUME THAT THE STARTER IS THE WORST HITTER (8TH BATTER) AND THE PITCHER
HITS 9TH AND WE PINCH HIT FOR THE PITCHER EVERY TIME, IT'S A LITTLE BIT EASIER
- OC = nextLI*{[PH(wOBA)-NEXTPH(wOBA)]}/1.15
- WHAT IS THE SPREAD IN wOBA IN AN AVERAGE BENCH?
- 10th FIELDING VALUE =
CHANCE OF 10TH OCCURING * LI OF 10TH INNING * [REPLACE(DEF)-STARTER(DEF)]
- 10th HITTING VALUE =
CHANCE OF HITTING IN 10TH * LI * [REPLACE(wOBA)-.025-STARTER(wOBA)]
---
Juuuust a bit outside!!
http://www.rightfieldbleachers.com
by Jack Moore on May 11, 2009 12:25 AM EDT reply actions 0 recs
I'm not smart enough to follow this
but “Late Night Sabermetrics” would be an awesome name for a column
I'm not a sabermetrician, but I do play one at Driveline Mechanics.
by devil_fingers on May 11, 2009 11:24 AM EDT reply actions 0 recs
... about Basebal Pornography
Beyond the Boxscore // Calling BJ Upton lazy is lazy.
by Sky Kalkman on May 11, 2009 11:48 AM EDT up reply actions 0 recs
Rule 34?
I don’t even want to think about how f’d up that would be – also: Minors.
by bs.uf15bosox9bears23 on May 11, 2009 7:16 PM EDT up reply actions 0 recs

by 











BtB on Facebook
















