Why is OBP% worth more than SLG%?

[oolalaa]

Can someone explain to me why OBP% is more valuable than SLG%? I have heard from various different sources that OPS% undervalues OBP% and overvalues SLG%. That OBP% is worth up to twice as much as SLG%.

I really don't get it. Clearly I must be missing something....

[Orioles5]

Just to be clear the SLG% is determined by taking total bases (single = 1 base, double = 2 bases, triple = 3 bases and home run = 4 bases) and divide it by at bats.

[Joltin' Joe]

Well to start with Slug has a max value of 4 whereas OBP has a max value of 1. OPS takes OBP and Slug at face value and gives equal weight to both despite the fact that their max value is not the same. So to use an extreme example, an OBP of 1.000 is more valuable than a Slug of 1.000. To use a more realistic example, an OBP of .400 is quite good, but a slug of .400 is only so-so.

[SamtheBravesFan]

I think the answer is simple: You can have a good slugging percentage and yet still be a poor overall player, and you rarely see poor players having high on-base percentages.

Just picking numbers out of my head, in the modern era, there are 180 seasons with batting average below .240 and slugging average above .400.

133 individual players have those seasons.

There are three with batting average below .240 and on-base percentage over .400:

Roy Cullenbine, 1947
Eddie Joost, 1956
Gene Tenace, 1977

I might be going backwards with this statement, but it might mean that having a skill to get on base is rarer and should be valued a little more.

[dominik]

Well to start with Slug has a max value of 4 whereas OBP has a max value of 1. OPS takes OBP and Slug at face value and gives equal weight to both despite the fact that their max value is not the same. So to use an extreme example, an OBP of 1.000 is more valuable than a Slug of 1.000. To use a more realistic example, an OBP of .400 is quite good, but a slug of .400 is only so-so.

this. I think it's a pure mathematical problem. If you just add two different numbers the smaller number will be undervalued. that would be like adding hits and HRs to evaluate the best hitter although not nearly as extreme since the numbers are still in the same ballpark.

for example the MLBs OPB this year is .319 and the SLG is .406. this means the SLG is 1.27 times higher. to weigh both values the same you would need to multiply OBP * 1.27.
(of course the coeffitient is not the same every year so we can't just use 1.27).

Also of course the weights of SLG are arbitrary and not correctly weighing XBHs by their run production potential but this is another story. OPS is basically a mathematically incorrect stat for a lot of reasons but it is still a quite OK measurement for hitting. Even I use it more than wOBA or wRC+despite knowing this is better since it is just more common in use.

[oolalaa]

I'll frame it slightly differently....

Why is (H + BB + HBP)/(At bats + BB + HBP + SF) inherently more valuable than (1B + 2x2B + 3x3B + 4xHR)/AB?

Maybe it's not? Maybe I've mis-understood?

[pheasant]

I'll frame it slightly differently....

Why is (H + BB + HBP)/(At bats + BB + HBP + SF) inherently more valuable than (1B + 2x2B + 3x3B + 4xHR)/AB?

Maybe it's not? Maybe I've mis-understood?

You are thinking of weighed OB%. And it is more valuable than slugging percentgage when measuring the value of a hitter. Some of the stat guys will correct me, but here's the basic concept:

For slugging percentage, if a single=1.0, then a double=2, triple=3, and a HR=4.

However, for weighted OB%, if a single=1.0, then HBP=.6, BB=.7, single=1.0, double=1.4, triple=1.7, HR=2.3.

THus, weighted OB% is much more valuble of a tool for measuring a players' hitting value compared to the slugging percentage.

[willshad]

Whoever said this is mistaken. Taken by themselves, slugging percentage tells you a lot more than OBP does. If we know, for instance, that a guy slugs .500, we know that he averages a half a base for every at bat. It really doesn't matter if it comes in the form of home runs, doubles , singles ,or whatever. If all we know is OBP, then it cold be half walks, almost all singles, or a ton of home runs. We have no idea, and it makes a HUGE difference.

Guys with a high slugging percentage will always be great hitters. taking a look at the lifetime slugging percentage leaders, of those who aren't still active, its pretty much HOFers, future HOFers, Coors field guys, or juicers.

[dominik]

You are thinking of weighed OB%. And it is more valuable than slugging percentgage when measuring the value of a hitter. Some of the stat guys will correct me, but here's the basic concept:

For slugging percentage, if a single=1.0, then a double=2, triple=3, and a HR=4.

However, for weighted OB%, if a single=1.0, then HBP=.6, BB=.7, single=1.0, double=1.4, triple=1.7, HR=2.3.

THus, weighted OB% is much more valuble of a tool for measuring a players' hitting value compared to the slugging percentage.

I think you are missunderstanding that. OBP is not more valuable than SLG. It's just that in OPS SLG is slightly overrepresented since it is a larger number. I think it is a pure mathematical problem (a 50 point increase in SLG is percentually less than a 50 point increase in OBP)

[Jackaroo Dave]

I'll frame it slightly differently....

Why is (H + BB + HBP)/(At bats + BB + HBP + SF) inherently more valuable than (1B + 2x2B + 3x3B + 4xHR)/AB?

Maybe it's not? Maybe I've mis-understood?

Your rephrasing is helpful, as it gets rid of OPS or OPS+, which has a fortuitously close relationship to overall offensive production, but is mathematically inane.

However, the phrase "inherently valuable" needs unpacking. As you can tell by the different approaches to your question, it is still unclear to some of us. Of what does this value consist? Value as a hitter or value as a measuring instrument?

My reflexive reaction would be, "No statistic has inherent value; statistics have various functional values. They are valuable if they help you ask or answer the question you want." But that's a singularly unhelpful response.

I am guessing that you are troubled by claims like the following:

"To make OPS+ a more accurate measure of hitting ability, you should multiply OB by 1.8 before adding it to slugging average."

This is just a magic number that happens to make things come out right. (e.g. If you compared a lot of teams' run scoring and their on base and slugging averages, slg+1.8*OB would be a more accurate predictor of their run ranking than just slg + ob.)

But I'm not really sure yet what you want to know. There have been a lot of discussions in the forum about ob and slg within ops, and you can look them up. I would also suggest browsing through Tom Tiger's baseball wiki, looking at various runs estimators. If my guess is right, then pheasant's answer will put you on the right track.

Dom is saying, correctly, that ob is "more valuable" because league average ob is lower than league average slg, so with respect to ob, slugging is "inflated." But I don't think that's what you're after. Whatever it is, it's a good question, because you have hit on a puzzling and rarely explained issue.

But I do want to know what you mean by "inherently valuable."

[Jackaroo Dave]

Guys with a high slugging percentage will always be great hitters. taking a look at the lifetime slugging percentage leaders, of those who aren't still active, its pretty much HOFers, future HOFers, Coors field guys, or juicers.

And high OB guys.

Rank 	Player (yrs, age) 	Slug%	Bats
1.	Babe Ruth + ( 22 )	.6897	L
2.	Ted Williams+ (19)	.6338	L
3.	Lou Gehrig+ (17)	.6324	L
4.	Jimmie Foxx+ (20)	.6093	R
5.	Albert Pujols (12, 32)	.6088	R
6.	Barry Bonds (22)	.6069	L
7.	Hank Greenberg+ (13)	.6050	R
8.	Mark McGwire (16)	.5882	R
9.	Manny Ramirez (19, 40)	.5854	R
10.	Joe DiMaggio+ (13)	.5788	R
11.	Rogers Hornsby+ (23)	.5765	R
12.	Ryan Braun (6, 28)	.5693	R
13.	Larry Walker (17)	.5652	L
14.	Albert Belle (12)	.5638	R
15.	Johnny Mize+ (15)	.5620	L

But the converse is not the case, true. Some high ob guys don't have a lot else going for them.

[oolalaa]

Your rephrasing is helpful, as it gets rid of OPS or OPS+, which has a fortuitously close relationship to overall offensive production, but is mathematically inane.

However, the phrase "inherently valuable" needs unpacking. As you can tell by the different approaches to your question, it is still unclear to some of us. Of what does this value consist? Value as a hitter or value as a measuring instrument?

My reflexive reaction would be, "No statistic has inherent value; statistics have various functional values. They are valuable if they help you ask or answer the question you want." But that's a singularly unhelpful response.

I am guessing that you are troubled by claims like the following:

"To make OPS+ a more accurate measure of hitting ability, you should multiply OB by 1.8 before adding it to slugging average."

This is just a magic number that happens to make things come out right. (e.g. If you compared a lot of teams' run scoring and their on base and slugging averages, slg+1.8*OB would be a more accurate predictor of their run ranking than just slg + ob.)

But I'm not really sure yet what you want to know. There have been a lot of discussions in the forum about ob and slg within ops, and you can look them up. I would also suggest browsing through Tom Tiger's baseball wiki, looking at various runs estimators. If my guess is right, then pheasant's answer will put you on the right track.

Dom is saying, correctly, that ob is "more valuable" because league average ob is lower than league average slg, so with respect to ob, slugging is "inflated." But I don't think that's what you're after. Whatever it is, it's a good question, because you have hit on a puzzling and rarely explained issue.

But I do want to know what you mean by "inherently valuable."

More valuable as a tool for determining who the better/more productive hitter is. That's basically what I'm looking for. I've heard and read that OBP% is a more telling and illuminating stat for judging a hitters performance than SLG% is.

I just don't understand why (Hits + Walks + Hit by Pitch / At Bats + Walks + Hit by Pitch + Sacrifice Fly) is supposedly a better tool than (Singles + Doubles + Triples + Home Runs / At Bats). To me, the latter looks like the more reliable indicator, mostly because the "Hits" in OBP% could be all singles with no doubles or triples or Home Runs.

But, as willshad and dominik have mentioned, perhaps I've mis-understood or been mis-informed. Taken seperately, OBP% is not better than SLG%?

[oolalaa]

I think the answer is simple: You can have a good slugging percentage and yet still be a poor overall player, and you rarely see poor players having high on-base percentages.

Just picking numbers out of my head, in the modern era, there are 180 seasons with batting average below .240 and slugging average above .400.

133 individual players have those seasons.

There are three with batting average below .240 and on-base percentage over .400:

Roy Cullenbine, 1947
Eddie Joost, 1956
Gene Tenace, 1977

I might be going backwards with this statement, but it might mean that having a skill to get on base is rarer and should be valued a little more.

I think this is part of my confusion. I understand that getting on base is important, but doesn't SLG% indicate that you've got on base, too?? Slugging percentage is seen merely as a power stat, but isn't a double more valuable than a walk?

[oolalaa]

You are thinking of weighed OB%. And it is more valuable than slugging percentgage when measuring the value of a hitter. Some of the stat guys will correct me, but here's the basic concept:

For slugging percentage, if a single=1.0, then a double=2, triple=3, and a HR=4.

However, for weighted OB%, if a single=1.0, then HBP=.6, BB=.7, single=1.0, double=1.4, triple=1.7, HR=2.3.

THus, weighted OB% is much more valuble of a tool for measuring a players' hitting value compared to the slugging percentage.

What do you mean by "weighted" OBP%? Are there different versions??

[SamtheBravesFan]

I think this is part of my confusion. I understand that getting on base is important, but doesn't SLG% indicate that you've got on base, too?? Slugging percentage is seen merely as a power stat, but isn't a double more valuable than a walk?

Of course a double is more valuable than a walk. Slugging average doesn't necessarily indicate you get on base. It's a ratio from batting results, which can be directly tied to batting average because they use the same dividend. That means slugging average shows the basic impact of a player's hits.

If on-base percentage is valued more, it is because a ratio of how often a player doesn't make an out.