With KBO free agency (aside from the fates of Yoon Suk-Min and Oh Seung-hwan being decided) already over, it is a good time to look back at the 2013 season in the Korea Baseball Organization. I will start with pitchers, the subject of this post. All 194 pitchers that threw in the KBO this year have complete WAR numbers for the 2013 season in the spreadsheet below.
For replacement level (the R in WAR) I used the traditional .320 winning percentage (18 % worse than KBO 2013 league average), instead of the current ~.29 rate used by Fangraphs or Baseball Reference. This is for no particular reason. I have no idea what a random veteran player in the Futures League is worth in the KBO. As you will see, I used three different versions of WAR for comparison, one based on runs per nine innings allowed (replacement rate was .69 per inning), one based on earned run average (.62 was replacement level), and one based on fielding independent pitching (.58). Then, using runs per 9 innings (which I labelled RPG), I created two different measurements instead of replacement level. The first is average, or WAA. The second is what I labelled as WAFP, meaning Wins over Foreign Pitcher. Foreign Pitchers gave up .5 runs per inning in 2013 in the KBO on a whole, and I thought it would be interesting to compare each pitcher to how you expect an average foreign pitcher to perform in the KBO.
The below spreadsheet are the WAR results for each pitcher in 2013. The sheet is sorted by RPG WAR, but you should be able to copy and paste the data in a spreadsheet, and sort it by whichever metric you want. The basic data (including the foreign pitcher data) and names are taken from MyKBO.net, while the league average rates (adjusted to replacement level by me) were taken from Naver.
If you have any questions or concerns about methodology (or even the results), please feel free to leave a comment below.