Question: What are the best MLB starting pitching free agents available for the 2009 season?
Note: I asked Tom Tango to comment on my methodology and here is his response: http://www.insidethebook.com/ee/index.php/site/comments/fip_extended/
Note: I did an update of pitcher that I believe the Royals will target:
Target – Pitcher the Royals should go after – young and good enough to help, but not too good to break the bank.
Reclamation – Pitcher with major past injuries and will be more of a chance – 1 year deal to turn career around.
Chance – Not the greatest pitcher, but may be signed for AAA/Pen and can be moved to starter
Why I asked the question: I wanted to see what free agent starting pitchers were available and the quality of the pitchers
I have been looking for a while to find a stat that uses only those attributes that are not effected by external factors that tell the strength of a pitcher. This is very important when comparing pitchers on different teams. W-L records are heavily determined by the teams offense, not the pitcher. Pitchers ERA is effected by how their bullpen handles inherited runners. Home Runs are determined by stadium elevation, distance to fences, wind direction and strength.
I had in the past like FIP (http://en.wikipedia.org/wiki/Defense_independent_pitching_statistics) as a measure, but because it takes HR into account and these can vary from one stadium to the next.
Another problem is that the attributes need to also be correlated from one season to the next. Baseball Prospectus,in the book Base ball Between the Numbers, examined what usefullstats are correlated from one season to the next and here are their results
Statistic - Year-to-year correlation
Winning percentage - .204
Batting average on balls in play (BABIP) - .272
ERA - .380
Home runs per batter faced - .470
Hits allowed per batter faced - .499
Walks (W) per batter faced - .676
Strikeouts (SO) per batter faced - .790
Ground ball (GB) percentage - .807
With the preceding information, a formula that takes W, SO and GB% into account was created.
First good events for the pitcher, SO and GB, will be given positive values, while BB will be subtracted away. The only problem is that not all ground balls hit into play will be an out. I decided to use the data from the work of Voros McCracken on BABIP historical determined that on average 29% of all balls hit should be hits and the rest should be outs. So GB will be multiplied by .71, getting the number of the ground balls will turn into outs. Finally the extrapolated number of GB outs and SO for the season are added together, W are then subtracted from the total and then the total is divided by the total number of batter faced over the season (TBF). Here is the equation:
(SO – W + (.7 * GB))/TBF
Currently I call the total Predictable Pitcher Quality (PPQ) until I come up with a more inventive name.
This stat is great way to compare pitchers and see how the rank without outside effects on them, stadiums, bullpen strength, run support, quality of competition, etc. As always I would love to have any feedback on the subject.
Here on the results of the available free agents and their PPQ number. Also the main starting pitchers for the Royals next season are included