THE BOOK--Playing The Percentages In Baseball

Thursday, December 09, 2010

Do players with speed skills age better?

Last month, I showed you the five-year aging curve for great players.

If you wanted one quick takeaway from that study, it was this:

If you take the simple average of the players from age [26 through 34], you get the following WAR for each of the next 5 years:
4.4
3.9
3.4
2.9
2.4

That is a drop of exactly 0.5 wins per season.  This is the rule-of-thumb WAR aging I’ve been using for a few years now.

The above players, in the season preceding those 5 years, had 5.8 WAR.

Would this kind of pattern also be followed by speedsters, or do they follow a more ageless curve or a more accelerated curve?  If I limit the players from my original study to those players who derive a great deal of their value from SB, CS (total SB runs of at least +20 over the preceding 4 seasons), I get the following over the next 5 years:
5.1
4.6
4.2
3.9
3.3

In the season preceding these 5 years, the speedsters had 6.6 WAR.  In this case, we have better players than the original group, which is somewhat of a surprise.

But, we are more interested in the pattern.  The speedsters lost 0.50, 0.41, 0.36, 0.57 wins in each season, compared to the 0.50, 0.50, 0.48, 0.50 that the general population of great players did.  So, a SLIGHT advantage for the speedsters.  If the general population is -0.50 wins, then the speedster population is -0.45 wins.

In the original study, and the above study, I used a threshhold of at least 4 WAR per 162 games.  The overall average of the speedsters was higher, for some unknown reason.  If I lower the threshhold to 2.5 WAR, I get speedsters who averaged a 6.0 WAR in the preceding season (exactly like my overall population from the original study).  Their aging over teh next 5 years is:
4.4
4.0
3.6
3.3
2.9

In this case, their aging drops were:  0.41, 0.46, 0.26, 0.40.  That’s an average of -0.38 wins lost each year.

Pending further research, let’s say that speedsters do age slightly better.  And if the typical great player loses 0.5 wins a season, let’s say the speedster loses 0.4 wins a season.

***

Among 29-31 year olds, like Carl Crawford, you have the following aging patterns, with the first line being the general population of great players, and the second line being the speedsters:
4.3 3.8 3.5 2.9 2.3 1.8 1.3
4.6 4.3 4.3 3.6 3.1 2.5 2.0

The total number of wins is 20.0 for the baseline (first line) and 24.4 for the speedsters.  Basically, because Carl Crawford is a speedster, he’ll provide some 4.4 additional wins, over and above what a regular player would have otherwise provided.  The following schedule would justify a 7yr 142MM$ payout:

That’s an 8% baseball inflation, the starting spot of 4.75MM$ per win, and a favorable aging pattern.  If we stick in the baseline great player, this is the schedule we get:

That’s 114MM$.  And that’s starting with the same quality of player.  Except this player is not a speedster.

Basically, Carl Crawford’s speed contributes to better aging, to the tune of 28MM$.  What seemed to me this morning like an overpay, may in fact be a perfectly sensible contract, only if the speed-aging pattern is something real.