In the first part of our winter leagues study, we looked at what the player performances said about each league’s level of quality. In Part II, we’ll look at what player performance in these leagues say about a player’s future.
The first thing to remember is that winter league statistics are forged in short-season leagues, so any stats represent a small sample relative to regular-season play. The highest AB+BB totals in these leagues over the last few years have been:
Arizona Fall League Drew Henson, 2002 166 Dominican W.L. Eddy Garabito, 2002 217 Puerto Rican W.L. Alex Cora, 2001 223 Venezuelan W.L. Alex Sanchez, 2000 262 Mexican Pacific L. Darrell Sherman, 2003 297
In order to test changes in player performances, I created a test set of players who met the following criteria:
- They had at least 250 plate appearances (AB+BB) in the regular season before playing winter ball;
- They had at least 75 plate appearances in winter ball;
- They had at least 250 plate appearances in the regular season after winter ball.
This gave me 391 players, or rather 391 sets of three player-seasons. All of the statistics were translated, using the difficulty ratings in the previous half of the article. From the summary statistics, it is apparent that they performed similarly as a group in each of the subsets:
- In the regular season before winter ball, players averaged 332 outs and a .230 EqA;
- In winter ball, they averaged 99 outs and a .231 EqA;
- In the following regular season, they averaged 315 outs and a .231 EqA.
You would expect that the correlation between player EqAs in the regular seasons would be stronger than the correlation between either regular season or winter ball, simply because the smaller number of PA from winter ball increases the variability in player performance. That is, in fact, exactly what you find. The correlations are:
- Between the two regular seasons .55
- Between prior season and winter .29
- Between winter and next season .33
Next, I sorted the players based on the difference between their equivalent runs per out in the prior regular season and in winter ball. I am using equivalent runs per out, not equivalent average; EqA is nice for display purposes, but it isn’t linear, and that is important for this study. The question at hand is, if a player improves between the regular season and winter ball, does that spill over to the following season?
The answer to that is a qualified yes–it does, if the difference is big enough.
To give people an idea of how big the differences are, a player with a .260 EqA (league average, by definition) will generate .172 equivalent runs per out (EqA, raised to 2.5 power, times 5 = .172). If he improved his offensive level by .025 EqR/out, his EqA would increase to .274. Improve by .050 EqR/out, and EqA is up to .288; improve by .075, and our formerly average hitter is up to .300. Declines of .025, .050, and .075 would reduce our average hitter to EqAs of .244, .227, and .207.
Change in EqR/out N Nsame Percent Chance >= .075 22 16 73 .992 .050 to .0749 30 21 70 .992 .025 to .0499 56 30 54 .748 0 to.0249 77 40 52 .676 -.025 to -0.01 87 43 49 .500 -.050 to -.251 60 35 58 .922 -.075 to -.051 40 30 75 .9997 <= -.075 19 16 84 .9996
“Change in EqR/out” is winter league EqR/out minus regular season EqR/out. N is the number of player-seasons within the range. Nsame is the number of players whose following season’s EqR/out changed in the same direction as their winter league EqR/out, although not necessarily by the same amount. Percent is 100*Nsame/N. “Chance” is the cumulative binomial probability distribution for Nsame and N, assuming a 50/50 chance for Nsame; the closer chance is to 1, the more likely this is a real effect, and not just random dumb luck.
Players whose winter league EqR/out scores improved by at least .05 EqR/run over the prior regular season had a 71% chance of having a better EqR/out (and hence a better EqA) in the following regular season than in the previous one. Players whose winter EqR/out dropped by .05 or more had a 78% chance of having a worse EqR/out (worse EqA) than in the previous year. Taken in total, players whose EqR/out changed by .05 or more are three times as likely to see their regular season EqA change in the same direction as their winter league performance. The average change was about one-fourth the winter league change.
Forty players improved their EqR/out by at least .050 points in 2003. In the list that followed, I’ve given the player’s organization (as of 2003), the winter league he played in, his change in EqR/out, his combined 2003 EqA, and his “expected 2004 EqA,” defined as 2003 EqA plus one-quarter the change in EqR/out.
2003 Exp 2004 Delta EqA EqA 1: Lou Lucca Mex PRL 0.146 0.223 0.248 2: Luis Figueroa Sea PRL 0.142 0.218 0.245 3: Richard Lewis Atl AFL 0.136 0.196 0.225 4: Emil Brown Mex MPL 0.122 0.257 0.275 5: Hiram Bocachica Det PRL 0.097 0.223 0.240 6: Victor Valencia Cle VWL 0.096 0.22 0.237 7: Omar Infante Det VWL 0.092 0.204 0.223 8: Julio Ramirez Ana DWL 0.089 0.214 0.231 9: Jason Dubois ChC AFL 0.088 0.238 0.252 10: Rudy Pemberton Mex MPL 0.088 0.222 0.238 11: Tom Evans Mex VWL 0.084 0.196 0.214 12: Luis Garcia Cle MPL 0.083 0.189 0.206 13: Luke Scott Cle AFL 0.078 0.224 0.238 14: Luis Rivas Min VWL 0.077 0.242 0.254 15: Jonny Gomes TB AFL 0.074 0.236 0.248 16: Ricardo Saenz Mex MPL 0.074 0.209 0.224 17: Scott Hairston Ari AFL 0.073 0.217 0.229 18: Luis Lopez Oak PRL 0.073 0.214 0.228 19: Papo Bolivar StL VWL 0.061 0.213 0.225 20: Carlos Hernandez Hou VWL 0.061 0.168 0.184 21: Cody McKay Cin DWL 0.058 0.201 0.213 22: Pablo Ozuna Col DWL 0.058 0.2 0.212 23: D'Angelo Jimenez Cin DWL 0.056 0.261 0.269 24: Luis Arredondo Mex MPL 0.055 0.204 0.216 25: Donzell McDonald Atl PRL 0.055 0.229 0.238 26: Jorge Sequea Tor VWL 0.055 0.229 0.238 27: Carlos Valderrama SF VWL 0.055 0.215 0.225 28: Luis Gonzalez Cle VWL 0.054 0.236 0.245 29: Juan Sosa Phi DWL 0.054 0.202 0.212 30: Mike Vento NYY AFL 0.054 0.242 0.251 31: Miguel Flores Mex MPL 0.053 0.199 0.210 32: Carlos Maldonado CWS VWL 0.053 0.214 0.224 33: John Pachot SF PRL 0.053 0.199 0.210 34: Izzy Alcantara Mex DWL 0.052 0.236 0.245 35: Juan Diaz Bal PRL 0.052 0.24 0.249 36: Adam LaRoche Atl PRL 0.052 0.252 0.260 37: Joe Espada SF PRL 0.051 0.189 0.201 38: Omar Garcia Mex PRL 0.051 0.238 0.246 39: Mario Santana Mex MPL 0.051 0.167 0.181 40: Raul Nieves SD PRL 0.05 0.176 0.191
By the same token, there were 39 players who lost .050 EqR/out or more.
2003 Exp 2004 Delta EqA EqA 1: Robert Machado Bal VWL -0.122 0.275 0.258 2: Justin Morneau Min PRL -0.104 0.248 0.230 3: Jolbert Cabrera LA VWL -0.103 0.268 0.252 4: Dallas McPherson Ana AFL -0.102 0.246 0.228 5: Craig Monroe Det PRL -0.093 0.261 0.246 6: Colin Porter Hou AFL -0.093 0.264 0.249 7: Jeremy Ware Mon VWL -0.086 0.226 0.210 8: Noah Hall Mon VWL -0.083 0.252 0.239 9: Armando Rios CWS PRL -0.08 0.238 0.223 10: Roberto Zambrano Mex VWL -0.074 0.248 0.235 11: Tony Alvarez Pit VWL -0.072 0.256 0.245 12: Jon Knott SD AFL -0.07 0.246 0.234 13: Santiago Perez Cin DWL -0.069 0.23 0.217 14: Andy Abad Bos DWL -0.067 0.254 0.244 15: Jamie Burke CWS DWL -0.065 0.252 0.241 16: Lorenzo Buelna Mex MPL -0.061 0.227 0.216 17: Pete Castellano Mex VWL -0.06 0.24 0.231 18: Noe Munoz Mex MPL -0.06 0.241 0.229 19: Koyie Hill LA DWL -0.059 0.216 0.204 20: Terrmel Sledge Mon PRL -0.059 0.277 0.268 21: Gabby Martinez TB PRL -0.058 0.254 0.244 22: Abraham Nunez Pit DWL -0.058 0.231 0.221 23: Anthony Sanders CWS VWL -0.058 0.224 0.212 24: Carlos Leon Bos VWL -0.057 0.218 0.209 25: Luis Rodriguez Min VWL -0.057 0.228 0.217 26: Chad Santos KC AFL -0.057 0.218 0.206 27: Ron Belliard Cle DWL -0.055 0.246 0.237 28: Donald Kelly Det AFL -0.054 0.226 0.216 29: Franklin Gutierrez LA VWL -0.052 0.231 0.221 30: Carlos Villalobos Mex MPL -0.052 0.255 0.245 31: John Gall StL MPL -0.051 0.255 0.247 32: Felix Jose Ari DWL -0.051 0.264 0.256 33: Dave Krynzel Mil AFL -0.051 0.215 0.204 34: Donny Leon ChC PRL -0.051 0.241 0.232 35: Mario Valdez SD MPL -0.051 0.239 0.230 36: Manuel Velez Mex MPL -0.051 0.212 0.203 37: Jimmy Alvarez Tor DWL -0.05 0.227 0.218 38: Treni Hubbard ChC MPL -0.05 0.254 0.246 39: Ramon Santiago Det DWL -0.05 0.219 0.210
For many of the players on these lists, their winter league performance really indicates nothing more than a return to form following an unusual regular season. Robert Machado, for instance, hit for a .227 EqA in 2001 and 2002 before busting out to .275 in 2003. His failure to hit in the Venezuelan league is hardly surprising, any more than the suggestion that he’ll drop in 2004. Virtually every player on the down list (all but four) had a 2003 EqA that was higher than their 2001-03 average, itself a compelling reason to expect declines in 2004; the winter league results just add icing to the sweet rolls.
Similarly, 30 of the 40 players on the up list were coming off sub-par 2003 seasons. Some of the interesting names that were NOT coming off sub-par 2003s were:
Luis Rivas, who hit for his normal .242 EqA last year, but stuck a .287 in Venezuela.
D’Angelo Jimenez, whose .261 last year was well above the .249 he hit in 2001-02, went out and hit for a .292 EqA in the Dominican. BP has been high on him for years; could this be the year he returns the favor?
Adam LaRoche hit for a .218 EqA in 2001-02, as a first baseman in the Braves farm system. Last year he hit .247 at Double-A, raised that to .256 after being promoted to Triple-A, and took that to .282 in Puerto Rico. The winter league numbers suggest that last year’s improvement was real, and that he could be a viable first baseman in the majors.
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