The Truth About the Miami Marlins, Marlins Park, and Run Scoring

A side discussion brewed in the comments section of yesterday's article on the disappointing 2012 that the Miami Marlins had. This side discussion was started by Fish Stripes reader miamiandy and centered around the Marlins' oppressive stadium dimensions in the brand new, beautiful Marlins Park. Over many comments, miamiandy's basic point was that the Marlins should have considered the marketing implications that a large, run-suppressing stadium would have on the franchise. Rather than go for a big stadium with high fences, the Marlins should have built at least a "fair" park that does not hurt hitters and allows for more runs to score. After all, fans are there to see runs, not defensive ball games.

Let us set aside for now the argument that fans are more likely to visit parks in which home runs and run totals are high. Marlins Park did indeed suppress one aspect of run scoring: home runs. It was no secret that the stadium's dimensions were likely to knock down a few homers with the combination of an extremely difficult center field, the traditionally difficult right field wall, and the increased length of the left field side heading into the Clevelander. Heading into this season, we all suspected that Marlins Park would make hitting home runs harder than it was at the old Sun Life Stadium.

This turned out to be true. The Marlins hit only 55 home runs at home versus 82 on the road. They also allowed only 58 homers at home versus 75 on the road, showing that the effect clearly worked on both the Marlins and their opponents as expected. Overall, players hit 1.40 home runs per game at Marlins Park versus 1.94 home runs in the other stadiums in which the Fish played.

But there is a slight problem with this argument. While Marlins Park certainly suppressed home runs in 2012, the one thing it did not do was suppress runs. Patriot released his yearly five-year regressed park factors, and this year included the first and only season of data for Marlins Park. Given that we only have one year of data, it is pretty heavily regressed, but the results might surprise you. Here are the Marlins Park factors (park factors, or PF, written based on a 1.00 baseline, meaning 1.00 is fair or league average)

It might surprise you to hear this, but the Marlins and their opponents scored the same number of runs at Marlins Park and away from it. Again, while it is true that, in 2012, Marlins Park suppressed home runs, the overall run scoring this season did not differ. Teams, including the Marlins, scored 668 runs in 81 games in Marlins Park and 665 runs away from the stadium. And neither side took advantage or were disproportionately disadvantaged by the stadium; the Fish scored 305 runs at home and 304 runs on the road, and their opponents scored 363 runs at Marlins Park and 361 runs away from it. The run scoring in 2012 was dead even.

What about the individual components aside from home runs? Surely there must be something that went up in Marlins Park to make up for the home runs going down.

On the road, it seems more singles were turned into doubles and a few more fly balls were turned into home runs overall, but the number of hits in total did not change much. Hitters notched 1384 hits at Marlins Park versus 1391 hits in other stadiums, so the change in offensive value appears to have come from the type of hits and not the number as well. Indeed, hitters hit .296 on balls in play at Marlins Park and .290 on the road, not a major difference.

As for the total batting lines, the above components reflect the results.

The line reflects what was obvious: Marlins Park suppressed home runs while keeping most other aspects equal. The park appears to be fair in every other fashion other than home run suppression, hence the difference in slugging percentage and wOBA.

Now, keep in mind that this is just one season of data, and the effects of a park are not well-elucidated even four or five years down the line, especially with new stadium cropping up every couple of years. But this is at least one sign that says that, even though Marlins Park does suppress home runs, its effect on run scoring itself is likely a lot less powerful. It is very likely that Marlins Park suppresses run scoring, but because the park seemingly keeps everything else equal, it is very possible that the effect is not large. The stadium is more likely to be close to AT&T Park (0.96 runs park factor) or Busch Stadium (0.97) than something like Petco Park (0.92) or Safeco Field (0.94).