Sunday, December 14, 2014

Do Park Effects Treat DiMaggio Appropriately?

98.7 is simple average of park factors for JoeD's years, from Baseball Reference. Yankee stadium comes out at about an average park only because it favored lefties and killed RHBs.

Click here to see how unusual his home/road splits were and how it affects is estimated value.

Now let's take a look at Yankee Splits from 1947-51 (I don't think the Baseball Reference Play Index has much data on these breakdowns before 1947).

Place Split BA OBP SLG OPS
Home LHB 0.269 0.362 0.448 0.810
Road LHB 0.280 0.359 0.432 0.791
Home RHB 0.270 0.355 0.396 0.752
Road RHB 0.275 0.355 0.402 0.757

Place Split BA OBP SLG OPS
Home OPP LHB 0.237 0.338 0.368 0.706
Road OPP LHB 0.270 0.367 0.386 0.753
Home OPP RHB 0.226 0.308 0.308 0.616
Road OPP RHB 0.255 0.342 0.376 0.718

Yankee RHBs actually did just a bit better on the road (an OPS of .005 better). We see a drop off for their LHBs (OPS falls .019).

But opposition RHBs had an OPS that was .102 higher at their home parks than in Yankee Stadium.. For opposition LHBs it was only .047 better.

So their is evidence that Yankee Stadium hurt RHBs and that a simple park effect may not accurately adjust their stats.


Matt Mitchell said...

This has me thinking about how Park Effects seem to me to be dependent on the quality of the ball club that claims that park as a home park. There's something interesting here worth exploring beyond Joltin' Joe.

Cyril Morong said...

Thanks for dropping by and commenting. Can you explain a little more on how the quality of the ball club might matter?