rLF - A Quick Stat
rLF
With all of the discussion about the value of defense recently, I decided to create a very rough and quick statistic to show its value in a way that even the casual fan can understand. I termed the stat "rLF" and the first test subject is everyone’s favorite third baseman, Adrian Beltre.
Adrian Beltre has often been a source of controversy between the Statheads and the casual fan. Although no one denies he is a good player, there is an argument as to whether or not he is worth his "value" – that is, the 11ish million he makes per year because of his (seemingly) low production offensively.
While much of the controversy lies in his basic stats, such as his batting average, slugging, HR’s, etc. – and I would argue his offensive stats themselves if you equate for his bad luck are already worth the contract – the other part of his game that is underappreciated is his defense.
As Jeff and others have pointed out of late, defense is not only underappreciated, it is also not hard to find. An ~average defender can be found in the minors for next to nothing. Finding a good defensive fielder with a good bat may be more difficult, but "average" is fairly easy to find, and you won’t have to trade the farm to get it.
Despite his error today, Adrian Beltre appears to have both. He has a good bat that has been unlucky of late, and a glove that may not have been the best in the American league last year (Screw You Brandon Inge) but was easily in the top 3. According to everyone that has watched him play, he is at least a 5 < X < 15 above average run saver with his glove. For the sake of argument, let’s split the difference and say that, with his glove, he prevents 10 runs from scoring on average.
As Jeff often says, a run saved is as important as a run scored. So what I decided to do was create a quick stat that shows the value of those runs prevented by converting it into offensive numbers.
Why offensive numbers? Because those are the statistics that make the most sense to the average fan. If you are trying to explain how much his defense positively affects his value, it would be far easier to say what Adrian Beltre would need to HIT to equal the same production if he was just an average defender.
I used average as the baseline because an average defender is not difficult to find. There may be a better way, but I’m not a stats guru and I don’t have a lot of time to spend on this… ever.
The Method
I entered Beltre’s basic stats into a spreadsheet (BB, Singles, Doubles, Triples, HRs). To find out the runs created by Beltre I used THT’s RC (Runs Created) stat. It was quick and easy, though there may be a better way to calculate these values. Again, if a run created is worth the same as a run saved, these two should be roughly equal in terms of overall value.
Next I added Adrian’s defensive runs saved approximation (10 runs, I termed it "Appx D" for simplicity) to THT’s RC, as an estimate for the total value of runs Beltre has contributed altogether (Defense+Offense). I divided the new number by the old RC, since the old RC only accounts for offense. Again for the sake of simplicity, I termed this value Ddif.
Finally, I multiplied this value by all of the core stats (this is where regression analysis would likely come in handy, in case he had an uncharacteristic amount of home runs, etc., but that’s not something I plan on doing). PA would not change because the purpose of this is to show what Beltre would have had to bat in order to equal the runs he saves defensively over average in the same amount of plate appearances. AB does change to account for the walks, but it is not multiplied by Ddif either, because it is based on PA.
(note: I’m still not positive if I should be including walks, but they will remain included for now)
I then found what the new and updated BA/OBP/SLG would be for Beltre. Assuming he saves 10 runs above average with his glove, if he was an average defender, he would have to bat .312/.359/.546 to produce the same amount. Or, if you want to put it in more positive terms, Beltre essentially had a .905 OPS in 2007 if he were an average defender.
(For those that are curious, at 5 < x < 15, Beltre is .294/.339/.514 < x < .331/.378/.579)
I’m positive there is a better way to do it, and I’m positive someone has likely done this before. But at least these numbers give you a very easy to calculate talking point if you are trying to explain why Beltre is worth the money. If he saves 10 runs with his glove above average, he was essentially a .905 OPS, rather than a .802 OPS.
I termed the stat rLF to stand for two things: Replacement Level Fan (as in, a number that casual fans can understand) and "Raul in Left Field." So, for fun, I’ll also address the latter of the two.
For Raul in 2007, if we assume he ONLY caused 20 runs to score below average (and I think it is possible it is more like 30 or more), Raul – as an average defender – put up a .231/.284/.380, or a .665 OPS.
So that is my quick stat using what little I know about [baseball] statistics. At the very least, it will make it a little easier to talk about the value of Beltre and other players to casual fans, and although I’m sure there must have been someone that has done this before, hopefully this works as an easier way to calculate it.
Edit - Jeff sent me Tango's RC. I like using the idea of Tango's RC more, since they are not dependent on the situation the player actually encounters, but an approximation of what each one is worth with the situation removed (much like defense). I'm not going to retype this whole thing, but you can find Tango's numbers here. And here is the result:
I like this result much better. Beltre becomes a 300 hitter with above average power and good defense. Ibanez is not god awful but for a left fielder he comes basically useless.
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19 comments
Comments
Used the wrong photo:

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by Librocrat on May 24, 2008 4:13 PM PDT reply actions 0 recs
Just to make sure you didn't make a mistake
When you compute RC for your adjusted stats do you get 91 runs for Beltre and 84 runs for Ibanez?
by Edgar for Pres on May 24, 2008 4:20 PM PDT reply actions 0 recs
Yes. Should be visible in the image above under "total"
RC is the only thing I have to work with without either being able to do the stats myself or know where to locate better ones. If you have a better stat than RC, though, I’d love to know about it.
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by Librocrat on May 24, 2008 4:30 PM PDT up reply actions 0 recs
Oh, unless you're asking me if I get 91 RC when I RECOMPUTE
in which case I don’t know the equation to give that a try. Also, THT’s RC uses some complicated stat that takes into account leverage, which is something I can’t do.
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by Librocrat on May 24, 2008 4:33 PM PDT up reply actions 0 recs
Yeah thats what I was asking
Ok, yeah I see its more complicated than some easy formula maybe. I’m just not sure you can multiply all his outcomes by one number. I’m afraid its not that simple but I’m a little brain fried right now and math seems much harder than normal so you might be fine.
by Edgar for Pres on May 24, 2008 4:38 PM PDT up reply actions 0 recs
What I originally wanted to use was some form of run estimation.
I could have sworn I remember Tango did something where a single was worth X runs on average, a double was worth Y runs on average, etc. I’d prefer to use that, as although it will be inexact to what he created in 2007 itself, it will give a good idea of a way to estimate each additional hit’s value, rather than assuming the hit was in high or low leverage, etc.
I searched for it and emailed Jeff as well, but I couldn’t find it. And since I’m not making this a long term project (rather I am just trying to find something I can calculate really quickly), I only plan on updating/editing it if it is easy, since all I’m trying to find is a quick and easy way to estimate an individual’s contribution with the glove in terms of offensive value.
That said, I agree completely that the stat itself is going to be highly inaccurate, due to the factors that go into RC’s equation. But I have a feeling it is not so far off that it is unusable, unless a player was in a surprising number of high leverage, bases loaded, etc., situations (or the opposite).
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by Librocrat on May 24, 2008 4:43 PM PDT up reply actions 0 recs
Edit using tango's numbers are above.
This should be more accurate in terms of imaginary estimated performance. The results are not quite as extreme, which is what I had originally expected when I did this, but they are still tremendously better.
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by Librocrat on May 24, 2008 5:12 PM PDT up reply actions 0 recs
Nice
If you have a little different motive you could also add in another correction for position by adjusting the runs too.
by Edgar for Pres on May 24, 2008 5:26 PM PDT up reply actions 0 recs
That I would be happy to do someday.
I’ve got too much to do right now, but if there’s any interest I’d be happy to try to add that. Shouldn’t be too difficult. Do you know where I can find the numbers?
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by Librocrat on May 24, 2008 5:58 PM PDT up reply actions 0 recs
To rehash some thoughts.
Tango’s numbers are all estimates. They have nothing to do with the actual amount of runs contributed on any given hit by Raul or Beltre. But in my opinion (dissension is encouraged) if we are going to estimate how many runs his defense is saving, we are also estimating how many runs his non-out production caused, all things being equal. Since we can’t know the imaginary importance of the runs saved, we should not hold players accountable for things beyond their control as well – at least for these adjustments. If I understand THT’s RC, that is not an estimate, rather it is the “exact” amount of runs contributed given the situations the players were in. In this case it is less ideal than Tango’s.
Anyway, I think this stat generally works for its purpose… also, hopefully all of this made some sense.
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by Librocrat on May 24, 2008 6:04 PM PDT reply actions 0 recs
What are you basing the D numbers on?
Secondly, I’m not sure what the point of this is. Pretty much everyone, even the most casual fan out there, even the most SABR resistant fan, understands a plus minus type concept, ie runs relative to average. You appear to be going the other way, converting runs relative to average into an OPS type number.
ZIPS: Milledge: 466 HR, 485 2B, 2282 hits, 278-379-524
by rfloh on May 24, 2008 11:13 PM PDT up reply actions 0 recs
That is exactly what I'm doing
because I completely disagree with you in every possible way. You claim they understand the idea of defensive value, and if that were true – then they would understand it. So you’re clearly wrong, because the whole point is that few casual fans actually understand defensive value. This way, we can turn defensive value into offensive value, which are stats that casual fans do understand.
Point a) Geoff Baker says Raul’s defense, however, bad, does not matter because his offense is really good. But by showing not just an example (saying “Hey, sure he may get a lot of runs, but he gives them up with his bad defense!!! OMG!) but by actually showing the equivalent of what he hit considering his defense, you can show even the most casual fan how bad a player he is when he is forced to play the field.
If you don’t believe me, then ask the casual fan in Seattle if Raul is doing well. They will say yes. Every time. So your theory that they understand defensive value is clearly false, because they are only considering offensive value when they are saying he is doing well. But by actually showing his offensive equivalent, by showing what he “needs to hit” to equal roughly the same value he brings to the team if he is an average defender, you see that if he were at least an average defender, and he hit a .695 OPS, he would bring the same value to the team. In other words, his defense makes his offense relatively meaningless (but using offensive numbers which fans tend to understand better – this is why I call it a “quick stat” – since it is a stat that is useful to prove a point, nothing more).
If this explanation doesn’t make much sense, let me know because I’m really drunk and I’ll try to re-explain it in the morning. Also, Firefox spell check, however poorly designed, is really useful. That is all.
Oh, and as far as what I’m basing my D numbers on, that was just what we’ve been talking about on LL, not an actual defensive projection. Normally, when we estimate defense we give an imaginary range like “Betancourt is -5 < x < 5 defensively.” To make it simple, I made it the middle of the range (0, or, in Beltre’s case, 10) but It works just as well if you assume the low end or the high end.
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by Librocrat on May 25, 2008 2:00 AM PDT up reply actions 0 recs
Well, I don't live in Seattle.
You guys are the only Mariners fans I run into.
I claim that they understand defensive value if the defensive value is explained clearly in runs relative to average. And how that runs number is derived is also clearly explained. Once they know that there are actual humans watching and scoring the games, and once you provide a simple example of how they can use a simple basic zone based system to compare players when watching games, casual fans seem to be willing to accept the zone based systems.
How many of the casual fans in Seattle have the Play by Play systems explained to them simply?
Why should a casual fan in Seattle accept your number? You don’t explain how the D numbers are derived, other than “that was just what we’ve been talking about on LL, not an actual defensive projection”. Why should the casual fan accept what you’ve been talking about on LL? The casual fan might feel that Beltre is 0 runs relative to average, instead of 5-10. How do your numbers convince him otherwise?
ZIPS: Milledge: 466 HR, 485 2B, 2282 hits, 278-379-524
by rfloh on May 25, 2008 4:21 AM PDT up reply actions 0 recs
Oh, now that I give you.
No one should except this number as a “stat” or use it for any analysis. The term “rLF” was meant to be funny, not like i expect this number to be listed anywhere in the future. What it is, however, is fast and easy to calculate. And the point would be to say: “Listen, you can see that he is slow. Let’s say over the course of an entire year, he allows 10 more runs to score than an average defensive left fielder…” And you can show that if he were an average defender, what he would need to hit to equal the same level of production.
Terming it a “stat” is more for fun. What it is is more of a conversation piece. If I can show that by Beltre saving ~10 more runs than average he is essentially a 300/350/520 hitter if he were average, then it is easier to explain why he is such a good player and it is easier to show how saving just 10 runs would translate into offense.
To put it another way, any time anyone on Geoff Baker’s blog wants to say that Ibanez is a better player than Beltre, there is a really fast and easy to understand calculation to show they are wrong.
Like I said, this is not a long term project that I plan on doing anything with. Only something I find interesting in all this defense talk and how it is not understood or appreciated by casual fans and the M’s FO.
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by Librocrat on May 25, 2008 1:37 PM PDT up reply actions 0 recs
Or to put it another way
here is Chris Dial’s very clear and simple explanation of what is Zone Rating, how the numbers are derived, and its’ weaknesses..
And his explanation of how to convert ZR and RZR into runs relative to average.
How casual fans are pointed to explanations like these, or the very clear and simple explanation of how plus minus works in the Fielding Bible, instead of being beaten on the head repeatedly with the numbers?
Also, why do you believe an OPS like number is easier to understand than runs relative to average? Even the most casual fan understands runs.
ZIPS: Milledge: 466 HR, 485 2B, 2282 hits, 278-379-524
by rfloh on May 25, 2008 4:31 AM PDT up reply actions 0 recs
Hey, awesome work Libro
So, do this for every player in the league, and see who has the best OPS
Relative to position, I’d think it’d obviously be Chase Utley or David Wright (last year’s stats), normally it’d probably just be Poo-holes.
http://seattlesportsmaniac.blogspot.com
by LantermanC on May 25, 2008 8:43 AM PDT reply actions 0 recs
If someone gave me what they think their defensive runs saved estimates are, I could.
I am not familiar with how good all the league is defensively. Though I suppose if I wanted to take the time I could use the conversion stats that rfloh listed above.
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by Librocrat on May 25, 2008 1:39 PM PDT up reply actions 0 recs
Don't forget positional adjustments
C = +10 runs per 700
CF/SS = +5 runs per 700
2B/3B = 0 runs per 700
LF/RF = -5 runs per 700
1B/DH = -10 runs per 700
or something close to that
by chrisisasavage on May 26, 2008 9:57 AM PDT reply actions 0 recs

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