Pretend it's March. (I came up with this idea now and would forget it by March so just go with it.) Fantasy leagues are starting, and you are down to two players to choose for your first round pick. One played in the World Baseball Classic, the other didn't.
Well, I'm sure everyone has their own opinions on whether the WBC has an impact on player performance, but I decided to take a look at the stats. Well, here we go.
Following is a listing of every pitcher on the USA World Baseball Classic roster. I have also listed their ERA+ from the season before the classic and the season after.
For those of you who aren't into sabermetrics, ERA+ is a statistic based on an adjusted ERA. It takes park effects into account and the average league ERA for that season.
For example: A 5.00 ERA in Colorado back before the humidifier would receive a higher ERA+ than a 5.00 ERA anywhere else. An average ERA+ is 100. The higher the number, the better the season.
Now before you jump on the flaws of using ERA+, I will show them myself.
1) ERA is a flawed stat in the first place. ERA+ does a decent job of correcting it by using Park Effects and adjusting for the average league ERA but it still can't correct everything.
2) Players picked for the WBC most likely are at the top of their game or are veterans on the downturn of their careers. So, naturally, you should expect a slight decrease in their ERA+.
3) Small Sample Size. Obviously, looking at data for only 12 guys won't be conclusive but I don't have all day to look up data from the other teams.
Roger Clemens: 226 193 -33
Chad Cordero: 224 134 -90
Brian Fuentes: 164 142 -22
Todd Jones: 190 116 -74
Brad Lidge: 184 84 -100
Gary Majewski: 139 95 -44
Joe Nathan: 165 283 +118
Jake Peavy: 134 99 -35
Scot Shields: 154 159 +5
Huston Street: 253 134 -119
Mike Timlin: 202 109 -93
Dan Wheeler: 191 176 -15
Dontrelle Willis: 151 112 -39
Totals: 2377 1836 -541
Avg/Pitcher: 182.9 141.2 -41.7
W/O Nathan: 184.3 129.4 -54.9
List Doesn't Include: Al Leiter (retired)
As you can see, every pitcher besides Joe Nathan and Scot Shields saw a decrease in their ERA+, sometimes major. A 41.7 average decrease in ERA+ is enough to question letting your pitcher pitch in the classic and removing Nathan's outlier makes it even greater.
While the pitchers still have a good average ERA+ in 2006, there is clearly a significant drop-off from the year before. Whether that's from the WBC or not can be argued but there is no arguing that there is an enormous drop-off in performance.
Now let's take a look at the offensive side and see if there are any major drop-offs here as well. I decided to look at OPS+. Just like ERA+, this stat accounts for park effects and the league average. Once again, an average OPS+ is 100 and the higher the number the better the season.
OPS+ has the same problems has ERA+ does but I feel it's the best single statistic to measure a player's performance. Win Shares could also be used but OPS+ is also easier to obtain so I went with that.
Michael Barrett: 110 121 +11
Brian Schneider: 97 72 -25
Jason Varitek: 122 83 -39
Derek Jeter: 125 132 +8
Chipper Jones: 151 154 +3
Alex Rodriguez: 173 134 -39
Mark Teixeira: 144 126 -18
Chase Utley: 132 125 -7
Michael Young: 131 108 -23
Johnny Damon: 110 115 +5
Jeff Francoeur: 126 87 -39
Ken Griffey Jr.: 144 99 -45
Matt Holliday: 114 137 +23
Vernon Wells: 104 129 +25
Randy Winn: 128 84 -44
Totals: 1911 1706 -205
Avg/Hittter: 127.4 113.7 -13.7
List Doesn't Include: Derrek Lee (injury)
Just from that list, even though on average the hitter lost 13.7 points in OPS+, it isn't a significant enough decrease to pin on the World Baseball Classic. Most likely, it is just a random occurrence or a flaw of the stat as I mentioned above.
It is interesting to point out that pitchers had a much more significant decrease than hitters following the WBC. This may be due to pitchers being more inconsistent or it is more likely that playing in the World Baseball Classic does impact a pitcher's performance during the season and not a position players.
Anyway, after all that, if you are down to two pitchers, I suggest you go with the one who didn't play in the classic. Two hitters? Disregard the classic. A pitcher and a hitter, both of which played in the WBC, clearly go with the hitter.
If anyone wants to study the players from the other teams and/or look at stats other than ERA+/OPS+, please let me know. I am willing to go more in depth with this if anyone wants to. Or you can do it on your own, but make sure to send me the results!