# Talk:On-base plus slugging

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## Untitled

The list of players with a career OPS above 1.000 could in my opinion be improved by marking active players and also noting the cutoff in terms of playing time (500 games? 3000 AB? Something else?) Is there a standard wiki way of denoting active players? basbeball-reference.com has them in bold, which is one suggestion. Imsdal 13:53, 30 June 2006 (UTC)

Why can't the math be done? I'm confused. Evil saltine 04:07, 23 Oct 2003 (UTC)

I've cleared this part up. The math is certainly not "inexecutable." Last time I checked it's possible to add numbers. Regarding whether OPS correlates well with runs--this isn't a POV issue. One can calculate the correlation coefficient, and that is that. Where the POV comes in is if you say that players should be valued for their OPS more than other factors--but the article never says that. From Baseball Prospectus ([1]):
                   Correl   RMSE
Batting Average .828    39.52
On-base Percentage      .866    34.16
Slugging Percentage     .890    31.56
On-base plus slugging   .922    25.54


As you can see, OPS has a very good correlation with runs scored per game. MichaelGensheimer 15:42, 18 May 2004 (UTC)

## Easy?

"Is easy to calculate"? That's quite a fraction there! -- Myria 06:00, 12 Nov 2004 (UTC)

Yes, it is easy. Any well-educated eighth grader should be able to plug numbers into a fraction like that and get the correct answer using pencil and paper. Really well-educated ones should have been capable of doing that for two years.Poihths (talk) 01:30, 7 September 2011 (UTC)
Well, what I think that means is that adding On-base percentage to slugging is easy to calculate, it's simple addition. Getting those two numbers requires a calculator, but they're logical formulas that are both easy to remember if you're familiar with baseball. --W.marsh 23:33, 4 August 2005 (UTC)
All you really need is the OBP + SLG box. Formulas for those are on their respective pages. If you must expand those out, then I think this is a case where finding the common denominator makes the fraction look a lot worse. (H+BB+HBP)/(AB+BB+HBP+SF) + (TB/AB) looks a lot cleaner. 172.184.169.24

OBP + SLG is faulty math. you can't add them that simply. Kingturtle 09:30, 13 January 2006 (UTC)

AFAICT the only distinction is roundoff error, right? If you calculated OBP and SLG to arbitrary precision and added them, you'd get the same results as with the formula given. -- Wed May 10 13:27:41 CDT 2006

## The Math

What would help is an example. Start with a single player's statistics. Show the OPS derived from simply adding OBP and SLG, then show the OPS derived from the more complicated formula shown. I don't have time to do this now, but I'll get to it later if nobody else is interested. -- JustSayin 14:40, 22 March 2006 (UTC)

Just add it like a normal fraction or decimal. If someone has an OBP of .250 and a SLG of .700, then their OPS is .950. 71.119.249.177 (talk) 00:57, 6 August 2008 (UTC)

Maybe I'm dense, but I don't understand why the OBP denominator isn't simply AB. Perhaps an explanation of this would be in order? — Preceding unsigned comment added by 107.137.64.139 (talk) 22:01, 30 April 2014 (UTC)

That is because AB does not include BB, SF or HBP. Thus if a player had two plate appearances, a walk and a strikeout, his AB would be 1, BA would be 0/1 = 0, OBP would be (1+0+0)/(1+1) = .500. Tennisjazz (talk) 18:33, 26 October 2016 (UTC)tennisjazz

## defending the changes I made regarding OPS calculation

Data as reported by espn.com on May 16, 2006:

Pujols OBP .469 SLG .833 OPS 1.302 Giambi OBP .480 SLG .654 OPS 1.134 Thome OBP .438 SLG .694 OPS 1.131

If you put OBP+SLG in a calculator, you get:

Pujols OBP+SLG 1.302 Giambi OBP+SLG 1.134 Thome OBP+SLG 1.132

The only difference is Thome's, and it results from rounding to the thousandths place in OBP and SLG. Therefore, you can get OPS from OBP+SLG. -—Preceding unsigned comment added by 128.61.136.233 (talkcontribs) 16 May, 2006

Didn't you just prove Kingturtle's point above? If Thome's is different, then the math is not precisely OBP+SLG. It's a quick and dirty approximation, yes, but not precise. You need to calculate it with a common denominator. I'm not a math person, though, so I won't tinker with the calculation in the article. -Phoenixrod 07:17, 9 June 2006 (UTC)

The way OPS is defined is mathematically the same as OBP + SLG. OBP is defined to be ${\displaystyle {\frac {H+BB+HBP}{AB+SF+BB+HBP}}}$ and SLG is defined to be ${\displaystyle {\frac {TB}{AB}}}$. So to say that ${\displaystyle OPS={\frac {H+BB+HBP}{AB+SF+BB+HBP}}+{\frac {TB}{AB}}}$, but does not equal OBP + SLG is bogus. It's also bogus to say that the sum of those two fractions is different than the fraction obtained by taking a common denominator and adding.

So it's not true that OPS needs to be computed as a massive fraction by using a common denominator. You can do that, and then if you convert to decimal form, there'll be some rounding error. But if you convert the two fractions to decimal and then add them, that's fine too, as long as you round off to a greater precision.

The only reason there is a difference in the computations above is that ESPN has rounded the OBP and SLG numbers to the thousandths place. The result of adding OBP and SLG (rounded to the thousandths places) certainly gives OPS; however, it may differ from the result of computing everything from scratch and converting to decimal at the end (rounding to the thousandths spot) by as much as 0.001. This just demonstrates the simple fact that if you want a number that is of a certain precision, you should use numbers that are more precise to compute it! To reiterate, OPS is OBP + SLG when considering exact numbers, but if you want OPS to some precision, you're going to need more precise OBP and SLG. --C S (Talk) 09:56, 9 June 2006 (UTC)

That's the most clear explanation of it that I've ever read. Thanks! I'll go back to non-math pursuits now. :) -Phoenixrod 19:04, 9 June 2006 (UTC)

What about sacrifice hits (bunts, squeeze plays?)99.238.12.117 (talk) 23:09, 16 April 2008 (UTC)
Sacrifice hits are not included in either the numerator or the denominator. BRMo (talk) 23:35, 16 April 2008 (UTC)
It's like significant figures in a science class. If you round before the end, you'll get a different answer.
29 + 25 = 54 which rounds down to 50; if you round before you get 30 + 30 = 60 71.119.249.177 (talk) 01:03, 6 August 2008 (UTC)

## Cardinal sin

None of the terms (BB, H, HBP, SF) seem to be defined anywhere on the page. Sure a true baseball fan might know them, but a math student would get no credit for this fancy formula! --Mike 19:08, 10 August 2006 (UTC)

I've added them. And Cardinals don't sin. Just ask Albert. Fan-1967 19:14, 10 August 2006 (UTC)
Sure they can. Just ask the Cubs. Hossrex (talk) 04:07, 26 April 2009 (UTC)

## Percentage

This might be picky, but is it kosher to call a number in the range [0.000, 1.000] a 'percentage'? It's common enough usage I'm sure, but just seems sloppy to me. 75.70.42.78 15:59, 7 April 2007 (UTC)

They may not technically be percentages, but that's what they're called. 71.119.249.177 (talk) 01:00, 6 August 2008 (UTC)

Can this article make it clear how to get park adjusted OPS+? —Preceding unsigned comment added by 68.0.212.61 (talk) 23:14, 16 October 2008 (UTC)

It is absolutely kosher to call a number in the range 0.0<->1.0 a percentage. Every percentage is exactly such a number. For example, when we calculate the percentage of pets in my house that are femaile, we divide 3, the number of female pets, by 5, the number of pets of both sexes, and we get 0.6. We then _format_ that number as 60%, which we obtain by a completely arbitrary process of multiplying 0.6 times 100. When we do that, we have re-expressed the value as a portion of 100, which is exactly the same as expressing it as a portion of 1.

Therefore, the statement in this article that batting average is not a percentage is absolutely wrong and should be removed. The batting average is calculated by dividing hits by at-bats. The result of that produces a number between 0 and 1 that expresses one value as a proportion of another, just like every other percentage calculation. We, by convention, particularly in the field of statistics, often print such a proportion as a decimal fraction instead of arbitrarily multiplying it by 100 and writing the result with a percent sign. Both epxressions show the proportion of hits to at-bats.

The true error is in calling the "batting average" an average. We actually should call it the batting percentage. An average, like a median, is a measure of where a middle point lies in a range of values. It would be an actual average if we were to examine the games in which a batter has played and show that on average he gets a certain number of hits per game. For example, a player that has played three games in which he got 0, 1, and 2 hits respectively would have a "batting average" of 1 hit per game. If he batted 4 times in each game, he would have a "batting percentage" of 3 divided by 12, i.e. .250. The first calculation examines the range of games in which he has played and determines a midpoint of his performance over that range; the other determines what proportion of his at-bats result in hits. It does not make sense to think of his at-bats as having a range of values; the value is always either zero (he didn't get a hit) or 1 (he got a hit.) Poihths (talk) 01:16, 7 September 2011 (UTC)

## Steroid Asterisk

I'd like to see references to McGwire and Bonds notated to show that their numbers may have been chemically altered. The best statistical years for both are tainted.

Tapered (talk) 06:19, 14 December 2008 (UTC)

Unless MLB does it, we shouldn't. Kingturtle (talk) 07:18, 14 December 2008 (UTC)
Until or if an official, comprehensive list appears, of everyone who ever used steroids and in which seasons, no asterisks connected with steroids are appropriate. Baseball Bugs What's up, Doc? 07:22, 14 December 2008 (UTC)
That is quite ridiculous. It is the same as saying that until we have an official, comprehensive list of everyone who ever wore their pant legs high or low, and in which season, we have no right to observe that Babe Ruth wore his pant legs high, even though we know he did. Certain players are known beyond a reasonable doubt to have used steroids, sometimes by their own confessions. However, I do agree that it is for Major League Baseball to make that call, not Wikipedia. Wikipedia is not an authority that determines official statistics in anything, let alone professional baseball.Poihths (talk) 01:23, 7 September 2011 (UTC)
That is the reason for one or two asterisks. Mark McGwire is an admitted user and gets **, Bonds gets * because he still won't admit it. The asterisk is necessary until the MLB allows the use of PEDs. — Preceding unsigned comment added by 192.203.222.87 (talk) 19:40, 13 April 2012 (UTC)

## Carlos Beltran?

Can somebody provide a source for the claim that Carlos Beltran is the postseason OPS leader? Baseball Reference disagrees.[1] Mcsnee (talk) 14:41, 1 November 2013 (UTC)

This was true before the 2013 postseason, but is no longer true. I've removed the image. Mindmatrix 16:34, 1 November 2013 (UTC)