The Updated Factor Grid

During the season, my Daily Grind column relied heavily upon what I called the Factor Grid. It’s a simple spreadsheet with a few of the most important park factors. With those in mind, fantasy owners and daily fantasy players can wisely select the hitters in the best offensive venues and vice versa. It’s a simple but effective strategy.

One of the drawbacks to the Factor Grid is it’s based on the previous season’s data. That’s because my most respected source of park factors – FanGraphs Guts! – only updates after the season. So in 2014, I made decisions based on how parks played in 2013.

Generally, this isn’t a problem since no team changed their park dimensions. Only one location really threw us for a loop – Dodger Stadium. In talking with Californians, a magic ether called the marine layer was less in evidence this season, allowing baseballs to fly farther. In other words, the power spike in L.A. sounds temporary.

Let’s move onto the update (or use the link):

The factors on FanGraphs Guts! are halved so users can do full season analysis. However, since I’m only interested in the stadium effects, I undo that adjustment. Since only whole numbers are reported, there is a +/- 1 error term. As you can see, Colorado is a magical place for offense. Moving down the list, there are about 10 stadiums with well above average home run rates. A few locales are extremely offense suppressant, like San Francisco.

How might you use this data in your offseason planning? Let’s use Josh Donaldson as an example. He was recently traded from Oakland to Toronto, which means he’ll frequently play in the fourth best park for right-handed home runs. The Rogers Centre has a 120 right-handed home run factor while the Coliseum has a 92 factor. In other words, we should expect 28 percent more home runs in Donaldson’s home games. Functionally, we’re talking about an increase of about four home runs. It’s a meaningful improvement, but it should only affect his cost by a couple dollars.

So, stadium matters when a veteran changes teams. The Factor Grid is also useful for selecting the most potent platoon players. Intuitively, you want to select hitters with fantastic home parks. For example, Drew Stubbs in Colorado, or perhaps Chase Headley at Yankee Stadium (if he re-signs). Adam Lind could be even more useful in Milwaukee. Even if these players were comparable to options in Miami, San Francisco, or Pittsburgh, they’re better targets because they have better opportunities.

That’s it. That’s the Factor Grid. It’s a simple and powerful tool. Questions?