Making (some) sense of RBI (August 20, 2003)
I just saw an entry on battersbox.ca somewhere talking about finding some metric with RBIs that takes care of the heavy context dependency of your teammates.
This is what I do... First of all, I don't look at RBI, but at RBI-HR, or RDI, or runners driven in. This takes care of the double-counting issue of the HR, which I go into great great detail on my website. Please go there to see the research on the subject. HR should come off.
Anyway, you are still left with the problem that you can't get an RDI unless you've got guys on base. And, it's easier to score the runner, if he's on 2b, or better 3b, and even better 3b with less than 2 outs. What to do?
1 - Figure out how often a league average player gets an RDI, by the 24 baseout states
2 - Figure out how often the player in question is faced with each of the 24 situations
3 - Multiply the two to get "expected RDI for a league average player, if given the opportunities of the player in question"
4 - Take the difference of #3 and your player's RBI-HR.
5 - That difference will tell you: (a) how good your batter is at driving in runners, (b) how lucky/clutch he might have been, and/or (c) the speed of the baserunners. (b) and (c) can be controlled further by a more laborious process.
To help you with #1, see the table below.
Anyone feel like doing the work for this year's players?
(You may also like this article on projecting runs and rbis I did.)
base outs RDI/PA
1st 0 0.05
1st 1 0.05
1st 2 0.06
.......
2nd 0 0.12
2nd 1 0.14
2nd 2 0.17
.......
3rd 0 0.50
3rd 1 0.46
3rd 2 0.20
.......
1st_2nd 0 0.20
1st_2nd 1 0.23
1st_2nd 2 0.24
.......
1st_3rd 0 0.57
1st_3rd 1 0.57
1st_3rd 2 0.29
.......
2nd_3rd 0 0.62
2nd_3rd 1 0.57
2nd_3rd 2 0.35
.......
Loaded 0 0.78
Loaded 1 0.81
Loaded 2 0.56
Rereading it, I see that Elias Bureau does virtually the same thing as I do, though I'm not sure how they handle the HR issue.
Posted 5:32 p.m.,
August 20, 2003
(#2) -
Jim R
Three questions.
(1) Where do you get the data for #1 and #2. I'm guessing this is some combination of Retrosheet and Ray Kirby's ASS, but if you can save me some hunting and pecking it will be appreciated.
(2) If its already written up what is the laborious process for controlling (b) and (c). [Skip this if its not written up]
(3) I just want to make sure my understanding of your (6) based on reading your linked discussion of the RDI. Our resulting number will still only tell us how good above average the player is at the RDI, as you have defined it. If one were to try and build upon this work and determine if there are skills for Ichiro's magic ability to hit a homer when it counts, etc., etc.; or the abiilty of Reggie to hit more clutch home runs than Barry Bonds, we still wouldn't be able to determine this without reconsidering the HR. That is, if the HR has a contextual value it still must be considered?
I ask this not to be a smart ass, but instead to understand and or extrapolate my worldly view on baseball. If one were to accept that (1) some batters were to change their approach on the AB based on the dynamics of the game; (2) they have differing performance parameters based on their approach.
For instance (and I am totally making this up), lets assume the famed Ichiro goes to the plate with one of two approaches: (1) Try to get a base hit and (2) Try to hit a homer. We have the instrumentation to determine the state of mind of the batter. In situation (1) Ichiro has this spread .15 1b; .1 2b; .03 3b; 0.02 HR; 0.04 NBIPOBO; .66 Out/error and in (2) .05 1b .08 2b .02 3b .08 HR 0.02 NBIPOBO, .75 out/error; or (1) .300 BA .340 OBA .520 SLG (2) .230 BA .250 OBA .590 SLG.
Now in probably 99% of baseball situations approach (1) is better than approach (2). I would imagine that if we use your base outs in combination with you win probabilities, we can likely find a neutral situation (that is not dependent on the pitcher, lineup, available personnel) where hitter (2) is preferable. That is trade an increase in 10% of making an out for a 6% increased chance of hitting a home run (or more appropriatly creating a run by driving oneself in). In this particular case, the ability to hit the HR, or make the decision to go for the home run would impact (a) and (b) of your number (5).
(As an aside, this is meant for illustrative purposes. I don't contend that anyone can be Dr. Vidro and Mr. Deer. However, I am inclined to believe that batters probably do change their approach based on pitcher, base/out, instinctual win probability, coaches instruction, count, etc. The differences in approach may likely yield very small changes in probability, and some approaches may in fact yield a decline in probability for any relevant positive event. I pose this just as a question for my understanding of the RDI discussion. Obviously we are not likely to have the instrumentation to measure this phenomena (if it exists) at any foreseeable period. I just want to understand the probable meaning of the outcome. I think I do understand of the macro ramifications of R+RBI-HR as a better predictor than R+RBI.
Posted 10:23 p.m.,
August 20, 2003
(#3) -
Greg Tamer(e-mail)
(b) how lucky/clutch he might have been
What does this include? Quality of pitcher? Quality of defense? Park effects? Place within lineup?
Now with the last one, I think it's trivial, but I mention this only because if I was hitting in front of Bonds, my sole purpose would be to not make an out. I wouldn't concern myself with trying to drive in runs. Or should I? I don't know.
Posted 10:45 p.m.,
August 20, 2003
(#4) -
Tangotiger
(1) Where do you get the data for #1 and #2.
All Ray Kerby, my lord and saviour.... uhmmm, my saviour anyway. The query is easy. Put "basesit:outs" in the key field, and "n pa rbi hr" in the output field, and "1999-2002" in the years field. 2 minutes later, you look prolific.
(2) If its already written up what is the laborious process for controlling (b) and (c). [Skip this if its not written up]
It's not written up. For (b) you figure out the following. Saying you haev a guy with 600 PA, 150 H, 50 2b, 30 HR, 25 BB, etc, etc... how many RDI would this guy get if he were to get a normal number of opps in each of the 24 base out states? (You have to figure how many RDI a double with man on 1b/2b, 1 out gets for the league, etc, etc.) So, what that gives you is "if my player performed the same across the 24 base-out states, how many RDI would he have gotten?" How many did he get? That's his clutch. For (c) you have a little tougher time. How often did he have Raines at 1b and 1 out? How does a speedster like this do when a double is hit? etc, etc. Kinda complicated, but something along those lines. You may also want to check the Tom Ruane article on Joe Carter at www.baseballstuff.com
If one were to try and build upon this work and determine if there are skills for Ichiro's magic ...if the HR has a contextual value it still must be considered?
I'm only considering the base/out state first of all. If you hit a HR, regardless of the base/out state, that's 1 run. If you happen to hit a HR with 2 men on, that's 2 RDI. So, you'll get "credit" for the RDI with the timely HR. You just don't need to get the credit for driving yourself in in a "timely" situation, since driving yourself in has nothing to do with the base/out state.
I ask this not to be a smart ass, but instead to understand and or extrapolate my worldly view on baseball. If one were to accept that (1) some batters were to change their approach on the AB based on the dynamics of the game; (2) they have differing performance parameters based on their approach.
There's no question that every batter/pitcher matchup is unique based on the context (inning/score/base/out/park, etc, etc). Therefore, absolutely everyone changes their approach to some degree, each hoping to perform optimally, and most likely everything cancelling out. But not quite, and certainly not in all instances.
We do know that certain base/out situations, like certain counts, are "hitter's states" and "pitcher's states". So, batters can leverage say the bases loaded 0 outs situation. Maybe they overcompensate, etc. A look at the league totals at each base/out state will show you the direction that these matchups go.
I do believe in all that. I don't believe we can say with much reliability who does what though. We just know general tendencies as to what they are probably doing. Clutch ability exists, but is more elusive to find than a pitcher's skill at preventing a hit on BIP. You won't be able to find the numbers to state at a high enough statistical significance that a player is clutch, whether he is Eddie Murray or Manny Ramirez. In fact, once you look at Murray by the 8 base states (and count the SF as a regular out... VERY IMPORTANT!), you will see that Murray's entire cluch value is when the bases are loaded. You can probably show some significance there, but I don't think anywhere else.
I hope I answered your issue, even though I went off to some other place!
Posted 10:47 p.m.,
August 20, 2003
(#5) -
Tangotiger
how many RDI would this guy get if he were to get a normal number of opps in each of the 24 base out states? (You have to figure how many RDI a double with man on 1b/2b, 1 out gets for the league, etc, etc.)
Sorry... I said that wrong. How many RDI would he get if he performed the same in all baseout states, given his actual opps in the baseout states?
Posted 9:15 a.m.,
August 21, 2003
(#6) -
tangotiger
(homepage)
By the way, I would only take this RBI thing so far.
If you want to get serious about it, I suggest you click the homepage link above. That was written 2 years ago, but applicable all the time.