Keith Law on WAR and Sabremetrics

[luismatos4prez]

Keith Law wrote a great Insider article on WAR and the most important statistics. Here are the highlights.

On WAR

Having a player's WAR, even if you know which version of WAR it is, is not in and of itself terribly useful unless you know the breakdown of the numbers that went into it. WAR is just the end of a process of normalizing different areas of a player's game

For Batters:

On wOBA

This is the best single metric I've seen so far for measuring a hitter's production on a rate basis. If you want one number to tell you how good a hitter was, this is my choice.

On OPS

Slugging is flawed because it weights each base achieved equally; the hardest base to reach is first, and the difference between a double and a triple is usually in the hitter's speed rather than its ability to advance runners already on base. Despite that, slugging, like OBP, is a good starting point for further analysis.

But for the love of Pythagoras, please don't add the two (OBP and SLG) together and pretend the result means anything. You have two fractions with different denominators -- OBP gives us a rate per plate appearance, while slugging gives us a rate per at-bat.

A point of extra OBP is worth a lot more to a team's run-scoring potential than a point of slugging.

For Pitchers:

On BB% and K%

There are two things a pitcher can do on his own that he can "control," These ratios are not subject to the noise present in pitcher stats that incorporate hit rates, balls in play or even home run rates

It's more instructive to use strikeout and walk percentage -- as opposed to strikeouts and walks per nine innings -- because some pitchers face more batters per inning than other pitchers, which means they get more chances to strike out or walk them.

On GB%

A ground ball in play is slightly more likely than a fly ball in play to become a hit, but less likely to go for extra bases; as you might imagine, a line drive put into play is the most likely type of batted ball to end up as a hit, but line drive rates don't appear to be within most pitchers' control and the data is rife with classification problems. Ground ball data is more reliable, and can help answer the question of whether that sinker actually sinks in meaningful terms.

[CA-ORIOLE]

Nothing all that controversial or that hasn't been often discussed on here I would think. I like wRC+ better than woba.

[weams]

Nothing all that controversial or that hasn't been often discussed on here I would think. I like wRC+ better than woba.

Tell me about how you use both. I am interested in your opinion.

[Frobby]

OPS is a flawed stat, but it's easy to calculate, and a better measure of a hitter than BA, OBP or SLG. Sure wOBA is a better rate stat than OPS, but there are about 10 people in the world who know how to calculate it. That's why OPS has its place.

[CA-ORIOLE]

Tell me about how you use both. I am interested in your opinion.

wRC+ is basically to woba what OPS+ is to OPS. wRC+ is park and league adjusted, woba is not. wRC+ is also more intuitive. Basically, if you said somebody had a woba of .330, most people would not know how to relate that like they could to OPS. wRC+ is on a scale of 100, so somebody with a wRC+ of 100 is average in creating runs. A wRC+ of 110 is 10% better than average in creating runs, etc.

Law isn't wrong when he says woba is great stat/input into the offensive WAR componenet, it's just that the actual input (adjusted woba) would be something closer to wRC+.

One minor issue with wRC+ (at least fangraphs version) is that it includes a break even point for stolen bases (not the overall base running component). The break even point is 75% which probably artificially lowers some players value (although not significantly).

[CA-ORIOLE]

OPS is a flawed stat, but it's easy to calculate, and a better measure of a hitter than BA, OBP or SLG. Sure wOBA is a better rate stat than OPS, but there are about 10 people in the world who know how to calculate it. That's why OPS has its place.

Bit of an exaggeration here. Knowing the value of the events (which are pretty stable), the formula for calculating woba is actually quite simple. Maybe a bit tedious and certainly not the A + B calculation of OPS.

[Tony-OH]

OPS is a flawed stat, but it's easy to calculate, and a better measure of a hitter than BA, OBP or SLG. Sure wOBA is a better rate stat than OPS, but there are about 10 people in the world who know how to calculate it. That's why OPS has its place.

Absolutely. I wouldn't make any judgement of any player based off of one stat alone, but OPS gives us a fairly meaningful discriminator. We know that a .800+ OPS guy is a pretty good offensive player just like we know one with a .600 OPS is not. OPS is way better than AVG, which was used for years and although I'm not putting down wOBA or any other stat, OPS is a pretty good if not perfect statistic that takes a player's ability to get on base and hit for power.

[eb45]

man I feel like I wrote a few thousand words about this a couple years ago. count me as another in favor of wRC+, though one not in favor of FG's interface as compared to B-R's.

does Law mention SIERA at all? because that's the pitching stat I like best.

[Can_of_corn]

wRC+ is basically to woba what OPS+ is to OPS. wRC+ is park and league adjusted, woba is not. wRC+ is also more intuitive. Basically, if you said somebody had a woba of .330, most people would not know how to relate that like they could to OPS. wRC+ is on a scale of 100, so somebody with a wRC+ of 100 is average in creating runs. A wRC+ of 110 is 10% better than average in creating runs, etc.

Law isn't wrong when he says woba is great stat/input into the offensive WAR componenet, it's just that the actual input (adjusted woba) would be something closer to wRC+.

One minor issue with wRC+ (at least fangraphs version) is that it includes a break even point for stolen bases (not the overall base running component). The break even point is 75% which probably artificially lowers some players value (although not significantly).

wOBA is based off the same scale as OBP so I really don't think it is difficult to see what is good and what is bad.

Bit of an exaggeration here. Knowing the value of the events (which are pretty stable), the formula for calculating woba is actually quite simple. Maybe a bit tedious and certainly not the A + B calculation of OPS.

The weights change on a yearly basis.

[CA-ORIOLE]

wOBA is based off the same scale as OBP so I really don't think it is difficult to see what is good and what is bad.

The weights change on a yearly basis.

My primary point was that people don't relate to woba as easily as OPS. If you do, I would say you're In the minority. In no way did I imply woba is a difficult concept to grasp. Just the opposite. The metric system is easy to grasp, yet how many people are really familiar with it.

"Fairly stable" implies the factors don't change very much.

[Can_of_corn]

FMy primary point was that People don't relate to woba as easily as OPS. If you do, I would say you're In the minority. In no way did I imply woba is a difficult concept to grasp. Just the opposite. The metric system is easy to grasp, yet how many people are really familiar with it."Fairly stable" implies the factors don't change very much.

I am often in the minority.

As for the metric system over 6.5 billion folks are familiar with it (Only Liberia, Myanmar and the United States of America don't use it.)

[DrungoHazewood]

OPS is a flawed stat, but it's easy to calculate, and a better measure of a hitter than BA, OBP or SLG. Sure wOBA is a better rate stat than OPS, but there are about 10 people in the world who know how to calculate it. That's why OPS has its place.

Sometimes people get bogged down in trivial details. OPS correlates to runs almost as well as wOBA, close enough that usually (but not always) it doesn't make sense to explain what wOBA is and what scale it's on and why anyone should care.

[DrungoHazewood]

Bit of an exaggeration here. Knowing the value of the events (which are pretty stable), the formula for calculating woba is actually quite simple. Maybe a bit tedious and certainly not the A + B calculation of OPS.

I don't have the linear weights coefficients memorized so I think I'm safe saying 99.5% of baseball fans can't calculate wOBA without some help. OPS is 90% as accurate and can be figured with data from a 1983 copy of the Sporting News.

[CA-ORIOLE]

Sometimes people get bogged down in trivial details. OPS correlates to runs almost as well as wOBA, close enough that usually (but not always) it doesn't make sense to explain what wOBA is and what scale it's on and why anyone should care.

The distribution between OBP and SLG isn't that significant on an aggregate basis. That doesn't mean the concept isn't important, if not significnat in individual circumstances.

[CA-ORIOLE]

I don't have the linear weights coefficients memorized so I think I'm safe saying 99.5% of baseball fans can't calculate wOBA without some help. OPS is 90% as accurate and can be figured with data from a 1983 copy of the Sporting News.

If you were given the aggregate statistics (and not handed SLG PCT and OBP) the calculations would be pretty similar in complexity and time. The main difference would be using coefficients instead of whole numbers. I have never chastised anybody for using OPS and I don't think anyone else has as far as I know. I'd prefer to look at wRC+ over OPS/OPS+. Quite frankly, I never really look at woba.