I decided to do this analysis on 2011 stats because there was a full season's worth of data, and honestly I'm so fed up with the 2012 season that I didn't even want to look at those numbers. I broke down the batter vs pitcher numbers for the Royals regulars (Sal, Moose, Hosmer, Getz, Escobar, Gordon, Frenchy, Billy) plus Yuni and Melky. I was looking at the opposing pitcher's FIP (calculation of HR, BB, K, and IP for those not sabermetrically inclined) to determine if the pitcher they faced was "good" or "bad". I used the league average FIP for a starter at 4.25 and reliever at 3.75 to determine if they were good or bad. I also split them between starting pitcher and reliever, so for each of the 10 players I produced 5 stat lines.
Vs Good Starters
Vs Bad Starters
Vs Good Relievers
Vs Bad Relievers
I then took those stats and divided them out by Stat/Plate Appearance, to determine the frequency in which they recorded those stats. For example, Billy hit a Homerun in 2.87% of his overall PAs in 2011, 1.58% against Good SP, 5% against Bad SP, 5.81% against Good RP, and 1.01% against Bad RP. So he crushed bad starters and good relievers, but struggled hitting homers against good starters and bad relievers.
I then took the frequency numbers and compared them to the season numbers to determine how much the splits differ from the total. So for those Billy HR numbers, you'd have 2.87% for the season, and each split is off -1.29%, +2.13%, +2.94%, and -1.86%, respectively.
For those keeping track, that's 150 total stat lines produced by this research: 10 players, 5 categories per player, plus those lines' frequency and difference. I'm not about to trash up this post with all 150 lines, so what I'll do is link to a Google Doc that has the spreadsheets, plus I'll post one player here so everyone can see what I'm talking about.
This is all the product of a very very boring day at work. Enjoy.
Google Doc of all stats
I think you have to click on this image to make it bigger. But as you can see, Yuni hit .210/.236/.300 last year for the Brew Crew against a good reliever and .304/.314/.370 against a bad starter.
I don't know, there are a lot of things to pick out of all of this data, so I'm gonna leave it up to you to just browse the Google doc if you want and point out any lines that you think stand out. Like for example, Salvy hit .091 last year against good relievers, but .444 against bad starters. I know it's only 29 games, but that is still quite a difference.
Or how about Getzy's .346/.382/.404 line against GOOD relief pitching last year? Not too shabby. He just really Getz it done.