In leagues with Runs and RBIs as categories, predicting how a player’s mix will change with a new team can be guessing. Some clown at Fantrax yesterday wrote the following:
“As for Headley, his value drops by going to a worse offensive team in a pitcher-friendly park. Part of the decline could be offset by a move up in the lineup since he mainly batted seventh for the Yankees last season.”
It could go up, it could go down, who really knows? While writing the statement, I needed a better answer so I created a couple quick and simple tool. If an owner can estimate a few stats, they can predict changes in plate appearances, Runs, RBI when a hitter moves from one team to another.
The key was to be simple and quick. For simplicity, only the following stats are needed.
- New likely lineup location
- Estimate of projected home runs
- Estimated games played such 150 out of 162 games as a percentage.
- Estimated Runs scored by a team. Used over on-base percentage because team level runs scored is easier to find and remember.
The estimated runs scored is the toughest value to come up with. I’d just go to FanGraphs team projection page to get a decent idea. Just take that year’s RS/G and multiply it by 162. Another method is to take the previous season value and plug it into the following regression equation:
`RS in Y2` = .575 * `RS in Y1` + 311
The goal is just to get a basic idea of possible changes.
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