The Value of WPA

by sonofmun on Aug 16, 2010 11:16 AM EDT

I was looking at Fangraphs front page and noticed that Joakim Soria leads all ML relievers in WPA. After a little looking, I noticed that he was 5th among all pitchers in WPA. My question is, what is the value of WPA? More after the jump.

Fangraphs tells us why we should care about WPA: "WPA takes into account the importance of each situation in the game. A walk off home run is going to be weighted more then a home run in a game that has already gotten out of hand. This makes it a great tool for determining how valuable a player was to his team’s win total."

It is that last sentence that gets me. "A great tool for determining how valuable a player is to his team's win total." So Soria has a WPA of 3.68. Zack Greinke, to pick an example out of a hat, has a WPA of 1.34. According to Fangraphs' definition, Soria would have more than twice as much value "to his team's win total" than Greinke. That sounds to me like Soria is more than twice as valuable to the Royals as Greinke. I suspect this isn't the case. But if WPA measures the amount that each player has affected the team's chances of winning, and if winning is the goal of baseball, then why isn't Soria more than twice as valuable as Zack? What am I missing?

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For a good, short WPA primer

see here. Basically, it’s a good “Story” stat to tell you how a player has been “numerically involved” in a team’s wins and losses, but it isn’t predictive nor does it really map very well on to player skill.

I'm not a sabermetrician, but I do play one at FanGraphs and Beyond the Box Score.

Can't get enough of me? Check out my Twitter feed.

by Matt Klaassen on Aug 16, 2010 11:23 AM EDT reply actions

So WPA

is RBI for Pitchers?

BOOM! ROASTED!

by GoBabies!! on Aug 16, 2010 12:32 PM EDT up reply actions

Heh... kinda

It works for pitchers and hitters. You start with a team’s probability of winning at the beginning of each PA, at the end of the PA, you take the difference for each team and assign it to the pitcher and hitter.

I'm not a sabermetrician, but I do play one at FanGraphs and Beyond the Box Score.

Can't get enough of me? Check out my Twitter feed.

by Matt Klaassen on Aug 16, 2010 9:19 PM EDT up reply actions

In the great experiment of the new statistics

the useful ideas will be refined over time, and the others will go the way of GWRBI.

by 2X2L on Aug 16, 2010 11:37 AM EDT reply actions

WPA is cool.

Fangraph’s little game widget that tracks WPA and Leverage Index is a pretty nifty way to watch a game. I wish my MLB app had that in it.

@Matt: Thanks for linking to that site, I never knew it existed before. It’s awesome.

by sfeldkamp on Aug 16, 2010 2:12 PM EDT reply actions

I don't think it's worth much for players.

I just don’t see the point of counting up the number of times a player caused a big swing in win probability. Most of the stats are context-neutral, but the “context” that WPA adds seems mostly irrelevant as a player stat – in looking at the progress of a game, sure, but not as a cumulative player stat.

www.writersjunction.com
in Santa Monica, CA

by SagehenMacGyver47 on Aug 16, 2010 2:15 PM EDT reply actions

Agree

Some people relate it to clutch, but it shouldn’t be related to individual players

- .-. ..- … – / – …. . / .—. .-. - .. . … …

by Jeff Zimmerman on Aug 16, 2010 4:55 PM EDT up reply actions

Google Thinks It's

WiFi Protected Access or Works Progress Administration. My father worked for the latter building Wyandotte County Lake, where I fished with utter futility for much of my youth, so I would rate it as pretty useful.

I used to be an A's fan until they left town and got good.

by philofthenorth on Aug 16, 2010 2:23 PM EDT reply actions

Google Thinks It's

I used to be an A's fan until they left town and got good.

by philofthenorth on Aug 16, 2010 2:23 PM EDT reply actions 1 recs

and plus hands

We have met the enemy, and he is us.

by Royal Kingdom on Aug 16, 2010 6:16 PM EDT up reply actions 1 recs

Sometimes When I

Hit “Post” it just sits there, so I try “Preview” and it usually works. This is the first time it’s double posted on me.

I used to be an A's fan until they left town and got good.

by philofthenorth on Aug 16, 2010 7:14 PM EDT up reply actions

I've seen it at a couple other SB nation sites today.

Glad I came, just wish I hadn't stayed so long.

People ask me what I do in winter when there’s no baseball...Rock Chalk Talk

by Warden11 on Aug 16, 2010 8:14 PM EDT up reply actions

I've seen it at a couple other SB nation sites today.

I'm not a sabermetrician, but I do play one at FanGraphs and Beyond the Box Score.

Can't get enough of me? Check out my Twitter feed.

by Matt Klaassen on Aug 16, 2010 9:19 PM EDT up reply actions 1 recs

Ha ha!

"I DARE you to make less sense."

by dejackso on Aug 16, 2010 9:24 PM EDT up reply actions

HUGE fan

the episode where he leaves to ~~host his own show~~ start his own lawfirm is flat out awesome

www.writersjunction.com
in Santa Monica, CA

by SagehenMacGyver47 on Aug 17, 2010 1:08 PM EDT up reply actions 1 recs

That's a great one!

Sealab, Harvey B, and Venture Bros made Adult Swim awesome…it has gone downhill in the last few years.

"I DARE you to make less sense."

by dejackso on Aug 18, 2010 1:05 AM EDT up reply actions

agreed on the downhill

"....The complex has been made simple, the unfathomable has been made fathomable, chess has turned to checkers and bridge turned into pitch. I feel better about myself after reading your post. Smells are smellier. My pants are looser in the waist....Philip ****ing Fitzsimmons. You brilliantly named sonofabitch...."

by SagehenMacGyver47 on Aug 18, 2010 12:59 PM EDT up reply actions