I sure hope I linked to the Hardball Times Correlation of Every Pitched Ball Tool last year. It is a web app that helps you compare two stats and see how they correlate, either in one year or compared to the next or preceding years.
It is an easy way to quickly test ideas, to see whether the data supports that one stat is a leading indicator of another.
Steve Staude has just released a hitting version of the tool.
Accompanying the two tools (and an accompanying spreadsheet with all the data) he explores some fundamental issues about batted ball data and strike zone data that point to all sorts of evidence to support or crush conjectures.
I happen to like this chart, which shows various rates on batted ball types.
Steve points out that BABIP on Fly Balls compared to Ground Balls makes it look like Ground Balls are better, but reminds us that since Home Runs aren’t included in BABIP, it is misleading. All the other stats give a better idea of the relative value of Fly Balls and Ground Balls.