We Were Prospects Once, and Young

as I made it out to be.

I don’t think evaluating players on a case-by-case basis is necessarily mutually exclusive from understanding that Jazayerli is showing a crazy market inefficiency.

The best part about Jazayerli’s study in my opinion, is that he’s actually measuring each pick (of young high-schooler vs. old high-schooler) against the expected value of all picks at that draft position. So he’s not saying that, uniformly, when you draft, you should draft the younger player instead of the older player available. He’s saying that categorically, the industry is over-drafting (in the sense of taking at a higher draft position than the player warrants) old high-schoolers, and under-drafting young high-schoolers (position-players only).

As Jazayerli says, this demonstrates a huge market inefficiency. The difficulty as I see it though, is how to implement the findings, and taking advantage of this market inefficiency, if you are planning a draft. Sure, maybe you’re over-drafting a old high-schooler by about five slots. But the problem is you don’t have a second pick five slots later. Remember, it’s not necessary that the older guy is worse than the younger guy. It’s that the older guy’s draft position should be a few slots lower, and the younger guy’s draft position should be a few slots higher. So if you really like the guy, what do you do about it? Or does this just mean that on your Big Board, there should be other guys (college hitters, college pitchers, high school pitchers) you like a lot more than him?

Two points that I find absolutely fascinating in the article. The first is saying that historically old high schoolers actually demonstrate a negative return on investment. Again, this isn’t saying that old high schoolers shouldn’t be drafted, but that they should be drafted way lower than they currently are. I guess it means you have to be really wary when evaluating old high schoolers in terms of the tools/numbers they are exhibiting, because in large part they may just be taking advantage of younger competition.

Which brings up the second interesting aspect of the study to me, which is that it seems to show a categorical problem with how scouts project high school position players. As much as scouts claim to think about “what this guy will look like five years down the line”, they seem to be not thinking about “what will a younger high schooler look like six months down the line, as compared to this current old high schooler I’m observing”, or at least not doing a very good job at this analysis. Is this projection difficult? As in, is projecting a young high-schooler six months away more difficult than, about the same difficulty as, or less difficult than projecting the abilities of an old high-schooler five years down the line?

Finally some food for thought. After reading this article, I took a look back at the 2009 draft that gave us Mike Trout to see where the relative ages of prospects were. There were 25 high-school position players taken among the Top 100 in the 2009 draft.

Five youngest: Marquise Cooper, Randal Grichuk, Chris Owings, Mike Trout, LeVon Washington

Five oldest: Mychal Givens, Jiovanni Mier, Billy Hamilton, Kelly Dugan, Donavan Tate

Scattered prospects in the middle with relative age ranks out of 25: Bobby Borchering (8th oldest), Wil Myers (10th), Reymond Fuentes (11th), Nick Franklin (13th), Matt Davidson (15th), Nolan Arenado (17th), Tommy Joseph (20th)

and I guess Part Two answers my questions….my bad

this is truly amazing:

Secondly, we can now estimate to what degree teams should be drafting younger players higher than they already are. If Player A is exactly one year younger than Player B, and they were both selected with the same pick in the draft, Player A should be expected to return an additional 1.17 Discounted WARP over his career. Because the value of draft picks does not go down in a linear fashion, we can’t say that one year of age is worth exactly X number of picks in the draft—X changes depending on where you are in the draft.

We can say that, using the above formula, 1.17 Discounted WARP is roughly the difference between the expected values of picks #24 and #100. In other words, a 17-year-old player drafted #100 overall has as much expected value as an 18-year-old drafted #24. If a player who might look like a third-round pick on talent alone happens to be a full year younger than his draft class, he ought to be considered a late-first-round pick.

That is a massive, massive impact. One year of age is the difference in the expected value of pick #25 and pick #11. It’s bigger than the difference between pick #5 and pick #8. And remember, this is even after adjusting for the fact that teams—at least some teams—may already be taking age into consideration and drafting younger players earlier than they would otherwise. They clearly don’t take age into account enough.

Even a six-month difference is meaningful. The difference in value between a player born in, say, October and in April is the difference in value between the #100 pick and the #43 pick, or the difference between the #30 pick and the #18 pick.

It’s hard to overstate the importance of this. I can’t say that major league teams have ignored age completely when drafting players, but age has clearly been subordinate to present talent, and this study argues strongly that this has been a mistake. If Player A grades out slightly better than Player B, but Player B is 6 or 12 months younger than Player A, teams have been drafting Player A first, and they should have been drafting Player B.

Many teams tend to avoid drafting the top HS players because of the cost; i.e., the need to pay them enough $$ to keep them from going to a college team. As a result, every year players slide in the draft until a team willing to go way over “slot” drafts them (the Nationals with A.J. Cole, for example). This gives the players an artifically low place in the draft commensurate to expectations, and so (all other things being equal) it’s natural that they would tend to generate a higher return than the college player taken the pick before or after. Their present ability is in fact not the same, because teams are also factoring in the amount of leverage the player has in contract negotiations (the college player has less choice/no choice depening on what year he’s in; the top HS players can pick their favorite college and put off signing).

I also probaby just missed it, but I didn’t see how he controlled out for players who were drafted young out of HS but didn’t sign.

Still fascinating, and I’ll have to go back and re-read the posts.

Beane was big on that James study you mentioned. I don’t believe he took a high school player in something like the first 15-20 rounds of that draft. I think when I read that, I just assumed the same was true today, but clearly that is not the case.

Definitely changes my perspective on the topic.

I believe it was mentioned in the article (or comments) that Francisco Lindor was over a full year younger than Starling, and even after his first pro year next season would still be younger than Starling is today.
Lindor will be an interesting case study because he fell just outside that top tier of players in most pre-draft rankings.
I didn’t realize Shawon Dunston was 19(!) when he was drafted out of high school.

How does Matt Thompson (Rangers system) have 30 WP in 88.1 IP? His stats look like he had issues with wild pitches in years prior, but not anywhere close to what he did this past year. I have read numerous times that he has a plus-plus breaking ball, was he paired with a catcher who was new to the position or did his control just fall off of a cliff?