About half my excitement over the new park factors by handedness that I discussed previously was that I finally had park factors to look at that separated events by the batter's handedness so that we could finally put numbers on. The other half was that I also had these factors for minor league parks as well, similarly compared aginst their respective league*. I went over Safeco Field's factors already, but I thought I would run down our various minor league affiliates as well.
The American League is a league, Major League Baseball is a level. Tacoma's park factors are compared against the rest of the Pacific Coast League, not the rest of Triple-A. League factors will come at a later date.
Most of these factors will not be surprising, but just as with Safeco, it's good to get a more exact bearing on just how harmful or beneficial these environments are when we peruse through our prospects. What interests me right away is how similar Tacoma's factors are to Seattle's. They're a little more extreme in areas and I'll take that opening to remind you that sample sizes on some of these (e.g. triples) are so small as to make the error margins -- even with three plus years of data -- rather substantial, but overall Tacoma follows the same general flow as Seattle.
| Factor | LH | RH |
|---|---|---|
| K | 107 | 107 |
| BB | 102 | 109 |
| HBP | 90 | 71 |
| GB | 94 | 92 |
| FB | 97 | 98 |
| LD | 103 | 107 |
| IF | 119 | 110 |
| 1B | 103 | 95 |
| 2B | 84 | 102 |
| 3B | 59 | 45 |
| HR/BIA | 85 | 86 |
| wOBA | 94 | 94 |
K, BB, HBP, GB, FB, LD and IF are all factored on a per PA basis since they are all discrete possible results of a PA. 1B, 2B and 3B are factored on a per batted ball basis. HR is factored by balls in the air (i.e. non-ground-ball batted balls). wOBA is based on what the league average line would have looked like given the above factors. A rough guide to 95% confidence intervals for these is given here.