Parking Troubles

Dave Paisley

Well, it is the post-season and everyone's all agog about the playoff matchups (well, except in Atlanta, Oakland, San Francisco and Chicago), but let's face it -- there's no more baseball until tomorrow, so we might as well take a look at some baseball background.

If you're at all remotely interested in baseball stats, or read Strikethree.com regularly, you realize that different baseball parks affect the game in different ways. During the season you'll hear pundits tell you how Camden Yards is a great home run hitters park, or that Dodger Stadium is tough to hit in. Sometimes they even acknowledge that Coors Field is somewhat beneficial to hitters (not that it stopped them pushing Todd Helton for MVP, of course.)

The trouble is, a lot of those nuggets of wisdom are flat out wrong -- made-up tripe by people who don't know what they're talking about and couldn't recognize a valid statistical analysis if it bit them on the posterior. What I'm about to show you isn't particularly difficult to figure out, nor is it terribly profound, but it does put park effect into some kind of perspective.

Before we even get to any numbers, it's important to mention that it depends what exactly you want to measure. Most analysis just uses runs scored in games at a particular park compared to runs scored in the road games of that team. That way you have roughly the same teams playing home and away and the difference is somewhat meaningful. But what if you measure OPS (On-base Plus Slugging) instead? What do the numbers look like? Or what about home runs? One good source of a lot of this information is the annual STATS Inc. Major League Handbook. What it doesn't show you, though, is any easy graphical way to compare parks.

I figured that runs scored, OPS and home runs are three good numbers to look at because they cover the conventional way of looking at park effects (runs) a more fundamental look at offense generated (OPS) and a key offensive indicator (home runs.) What I've done is generated the park effect numbers for those three categories, ranked the ballparks in order of OPS park effect (the most fundamental measure of the three) and then superimposed the other two park effects for comparison to see how well they relate. Here's the AL:

1.00 is a neutral number, while a number greater than 1.00 represents a more hitter-friendly park, while a number below 1.00 indicates a pitcher-friendly park. The red line is OPS park effect, and it varies from a high of 1.08 in Kansas City to a low of .90 in Seattle. Yes folks, Safeco field is a tougher place than any other to hit in. The blue line, runs scored, varies a bit more widely, but follows the same trend.

Although KC tops the OPS list, it is only marginally more homer-friendly, while Texas and Comiskey have been very friendly to home run hitters this year. (Remember that the White Sox hit a lot of homers all around, but they hit more at home than on the road, as did their opponents.)

Caution: unexploded myth ahead! The Metrodome in Minnesota has long been supposed to be a great home park, but is it? Despite having the highest runs scored park factor, homers are actually significantly below average. Then there's Yankee Stadium -- hitter-friendly this year for a change, and extremely homer-friendly.

The interesting points here are the wild variations in home run factor. Fenway has always been tough for home runs, for obvious reasons, but the first year at Comerica shows why it will be tough for the Tigers to retain Juan Gonzalez or recruit someone of similar hitting stature. If it's that tough to hit homers, then elite sluggers aren't going to want to sign with your club. The same goes for Safeco, too, which may see some changes to help the offense out a little over the offseason (and help retain the services of a certain Mr. Rodriguez, too.)

Park factors do have an effect, sometimes not so subtle, on how a team recruits and who they have a chance of signing. A very defensively oriented park may attract pitchers, but it will deter sluggers. The converse is also true. Before we get into that in detail, here's the NL picture:

And here we see just how huge an anomaly Coors Field is. While the AL numbers varied a bit, none of them got more than 10% away from the average, and the same is true for all NL parks except Coors Field. With +24% in OPS, +65% in runs scored and +80% in home runs, it's a different baseball world. And I still think that most fans and pundits don't realize how huge an effect that is.

How many elite pitchers have the Rockies recruited? Darryl Kile was the highest profile guy to sign, but his failure will only deter other, better pitchers for ever considering Colorado as a home base.

Taking Colorado out of the NL mix would show a similar range to the AL -- nothing terribly out of whack.

There's one more bubble to burst here. Note that Wrigley is sub-par in all categories. Maybe the wind wasn't blowing out most of this season? The other notable effect is Houston, where Enron Field shows up as second to Coors in all categories. I suspect that will be taken care of by some subtle changes over the offseason, and how long can that stupid flagpole and slope stay out there? What's next -- a shot from the mystery outfield gunner as center fielders attempt to catch balls?

about the author

Dave Paisley feels that in the interest of MLB's newfound "family friendliness," a kiddie playground should be installed where the Enron Field flagpole currently stands. Suggest that an outfielder catching a fly from atop the monkey bars should be awarded two outs at drdjp@strikethree.com.