Monday, December 24, 2012

Rookies, Velocity, and Minor League Projections

In what is my final planned post on this subject (maybe something else will come up), I wanted to look at what translated into success in the Majors better, minor league statistics or fastball velocity. So I looked at rookie qualified pitchers from 2009-2012 (via FanGraphs), and compared velocity (again, via FanGraphs) versus ZIPs projection systems for that season versus their FIP - that season.
ZIPs uses a version of MLEs (Minor League Equivalents, and idea by Bill James not really used in the scouting or prospecting circles, but still used some in advanced fantasy and projection circles. If one wanted to really simplify it, it is basically how minor league statistics translate to the Majors. I've used my own, with varying levels of success, but they did seem to outperform ZIPs) that creator Dan Szymborski calls "translations". If you want to break down what I am doing here, I am basically trying to see if minor league numbers or velocity is more predictive.  I couldn't get a hold of the ZIPs 2011 spreadsheet, so we are looking at 2009-2010, and 2012 ZIPs projections. However, we are looking at all rookie eligible pitchers from 2009 to 2012 when it comes to velocity. I used ERA, even though I would rather have used ERA +,  but the 2009 projection didn't have ERA +.The best 16 pitchers according to ZIPs projections (the ones below 4.00 ERA)had an average of 105.375 FIP -. The rest of the breakdown:

ZIPS 4.00-4.20 ERA: 79.7 FIP -
ZIPS 4.21-4.39 ERA: 92.6 FIP -
ZIPS 4.4-4.59 ERA: 103 FIP -
ZIPS 4.6-4.79 ERA: 96.1 FIP -
ZIPS 4.8-4.99 ERA: 112.8 FIP -
ZIPS 5.00-5.19 ERA: 107.2 FIP -
ZIPS 5.20-5.39 ERA: 96.6 FIP -
ZIPS 5.40-5.59 ERA: 103.7 FIP -
ZIPS 5.60-5.79 ERA: 102.5 FIP -
ZIPS 5.8-5.99 ERA: 103.1 FIP -
ZIPS 6.00 and over: 103.5 FIP -

It is hard to make much sense of this order. The best ZIPs pitchers were actually some of the worst, while the second set of ZIPs pitchers were actually the best. The regression order doesn't make a lot of sense and is sort of jumbled.

 (If for some reason you want the spreadsheet or the PDF version of the data, sorted by either ZIPs, Velocity, or FIP -, just email me. Blogger won't let me upload the file on the blog. All I did was use FanGraphs and exported the data I wanted and then manually plugged in their ZIPs projections from that year.)

By velocity:
97 MPH + (top 9): 72.25 FIP -
95-96.9 MPH: 87.54 FIP -
93-94.99 MPH: 98.65 FIP -
91-92.99 MPH: 110.17 FIP -
89-90.99 MPH: 106.95 FIP -
88.9 MPH and lower: 112 FIP -

This isn't perfect correlation by any means, but it appears to be pretty darn predictive. In our series of looking at the correlation of velocity and statistics between levels, there is no question that velocity was better, even better than advanced statistics. The actual correlation between velocity and success in the future league varied, but it seemed to be solid, especially here (the strongest correlations were here and from the Ni-gun to the NPB).

No comments:

Post a Comment

Post a Comment