You guys constantly refer to someone who has an OPS+ of 130 as having and OPS "30% better than the league average."

In 1993, Mark Grace had an OPS+ of 130. But his OPS wasn't 30% better than the league average. He had an OPS of 868, and the league OPS was 755.

His OPS was 15% better than league average.

Look also at Babe Ruth - career OPS+ of 207, but his OPS wasn't 107% better than the league. His career OPS was 1.164, and the league was .753. His OPS was 54.6% better than the league.

Not that it is a big deal, but I figured you guys should just be careful with your terminology.

And ERA+ does in fact work that way. An ERA+ of 130 reflects an ERA 30% better than the league.

No your wrong. OPS+ factors in park effects. You can't look at raw OPS and determine how much better than average he was.

He's right. OPS+ is essentially OBP+ plus SLG+ minus 100. So if a player's OBP is 17% anove league average and his SLG is 13% above league average, he will have an OPS+ of 130. But that does not necessarily mean that his OPs is 30% better than the league's. It's a good point, Robertson, and probably part of the reason that you see so many OPS+'s higher than ERA+'s.

Yea, but isn't OPS a combination of those two? 17+13 is 30. So they're OPS+ should be 30% higher.

You guys don't give people any credit, do you?

The League OPS numbers I quoted were park adjusted, from baseball-reference.com.

The .755 OPS+ he used for Grace was park adjusted. He was not using raw OPS. The league average without adjustment was .726.

Whoops. Beat me to it.

Oh, alright. Sorry about that.

I have to admit, every time I wrote "had an OPS 30% higher" meaning an OPS+ of 130, I wondered briefly if I was over simplifying.

Wouldn't it be a whole lot simpler if it WAS just OPS/park adjusted league OPS?