Prospecting

Back in the early 90’s, when I was collecting baseball cards and trying to find the next superstar, I started getting into stats and number-crunching. That’s how I learned to use Excel.

I first got into it when spotting Manny Ramirez’s gaudy high school baseball numbers. I figured there must be a way to analyze some of these numbers and run some sabermetric formulas on them to figure out who was going to be good. If I could buy the right rookie cards, they might be good investments. So I started looking at stats of young players (mostly on the backs of baseball cards, and later Baseball America) and used Excel to come up with different ways to weight and analyze the numbers.

I started getting pretty confident with what my “prediction” formulas were spitting out. My numbers in 1991 screamed that Manny Ramirez and Chipper Jones and Frank Thomas and Jim Thome were going to be big stars. Keith Mitchell, in particular, was supposed to be the second coming. Unfortunately, they screamed that Brian L. Hunter and Francisco Cabrera and Rich Aude would be big stars, too.

In the ensuing years, card companies were making it impossible for the average collector to keep up. I began to realize that all my alphabetized rookie cards in plastic sleeves were pretty much worthless, and that all the time and energy I had poured into my baseball card collection was pretty much a waste. With that, I lost interest in prospecting. Instead, I turned my baseball attention to a new numbers game, a historical simulation league called the HOFL, and that’s kept me busy since 1995.

The New Hype

At the beginning of the 2010 season, Jason Heyward came onto the scene with more hype than most rookies in recent memory. I felt a little tickle down below, knowing that I could probably take a closer look at the numbers and figure out, “How good IS this guy, really?”

So I fired up Excel and took a close look at Heyward. Once I was at it, I found a bunch of other names to plug in to compare. Back in the day, I knew half the players in AAA, but now I found myself entering names I had mostly never heard of.

I’m a lot smarter now. I know things about how players grow and develop that I didn’t really understand back in the day, and there are things you can look for in the numbers that didn’t occur to me in the Keith Mitchell days. So I kicked around some ideas, crunched some numbers, and came up with some new formulas that might be better at predicting minor leaguers will be able to hit in the majors.

The Formula

My formula takes into account the kind of power a player showed in the minors, with the projection that some of their doubles and triples in particular might turn into additional homers as they get bigger and stronger. It also takes into account a batter’s “eye” by preferring guys who are able to draw a walk and avoid the strikeout. If they don’t have an eye in the minors, they’ll usually (but not always) get hammered in the majors. Lastly, I look at age. Guys who get to the majors quickly are usually much better than guys who linger in the minors since a) the fact that they were rushed to the majors usually means that they are something special about them that may not be reflected in the stats, and b) they get to spend their formative years playing against the best of the best.

Here’s the nitty gritty, in case you want to try setting up your own spreadsheet:

Power Potential = (1B * 0.5 + (2B + 3B) * 4 + HR * 6) / AB

Y Score (from Bill James) = 24 – (age * 0.6)

Years of Improvement = MAX((28 – Y Score), 1)

Age Modifier = Years of Improvement ^ (1 / 10)

Eye Modifier = LOG(BB / SO, 100) + 1

Prospect Score = Power Potential * Age Modifier * Eye Modifier

After all the numbers are crunched, the final score, by chance, works out to look a lot like a slugging percentage. According to my system, a .400 guy is not that great of a prospect, while a .800 guy is a real slugger.

But it’s not perfect. So that everyone is ranked on the same scale, I only use minor league stats. Minor league stats are sometimes incomplete. And the numbers I use are not normalized for level, league, or park, so batting .350 for A-ball High Desert counts the same as batting .350 in the AAA Durham. When I can get reliably normalized minor league stats, I’d love to run the numbers again.

Also, there’s an assumption that players are promoted according to their ability, so that they are always facing equivalent competition. This is generally true in most cases, but when there’s a guy festering in A-ball and killing it vs. another guy lingering in AAA and struggling, the A-ball guy will “look” significantly better even isn’t necessarily better.

And for now, I’ve just looked at batters. Maybe pitchers will come next, but pitching can be a little trickier to predict in a lot of ways.

Today’s Future Stars

Who are today’s future stars? Let’s look at current minor leaguers and recent call-ups and see which of them are most likely to hit in the majors:

Mateo, Myers, and Sharpley have barely played, so they’re definitely iffy until they get more playing time under their belts. Sands looks solid, and he’s killing it this year. Posey and Weiters are already establishing themselves in the majors. Alex Gordon, for some reason, is trying desperately to keep a major league job. Why can’t he hack it? Mike Stanton looks like he’s for real. Carlos Santana just made his major league debut today. I’ve pined over Jaff Decker in the past, but he’s been screwing the pooch this year, so he’s moved down quite a bit. And there’s Jason Heyward, barely making the top 25. He very well could be one of those special guys who was rushed through the minors and never got a chance to stick around and kill it. Time will tell.

There will obviously be a few surprises both ways, but I’d feel pretty comfortable betting that the top 10 or so will become quality major league hitters. Check back with me in 5 years.

For shits and giggles, I plugged in Bryce Harper and his junior college numbers. Off the charts at 1.720. But junior college doesn’t mean squat. I can’t wait until he gets some pro experience so that I can plug those numbers in.

Yesterday’s Future Stars

After comparing today’s rookies, I decided to go back and add today’s stars to give me a glimpse of what they would have looked like as rookies. How did guys like Ken Griffey Jr. and A-Rod rank when they first came up? What about stars of the 80’s, like Mark Grace and Darryl Strawberry and Jack Clark? And the highly touted rookies like Gregg Jefferies and Todd Zeile? What about those fringy guys who could kill it, like Ken Phelps and Ron Kittle? I was really curious how all these guys would compare with each other as rookies.

According to my numbers, here are the top 25 historical minor league future stars of the last 30 years, listed with with the player’s first real season in the majors. Interesting to see who panned out.

Any surprises here? I think so. Travis Lee fucking killed it in the minors, but that was with limited playing time, lingering in a hitter’s park in a hitter’s league in A-ball for longer than he probably should have. Even in the 80’s, I knew Phelps could hit but was never really given a chance. Alvin Davis is a bit of an enigma. He should have been even better than he was. What happened to him? Drugs? Injury? Burrell was good for a short while but seems to have petered out. Kapler had more potential than I thought. How come he never put it together? Billy Butler’s for real. Jeremy Giambi? Did he disappear because he stopped using his brother’s steroids?

Everyone else seems to fall more or less where I’d expect them to fall.

The Historical Best

Some other names that are fun to look at:

Look at Willie!

Amazing how some of these guys, like Brett and Schmidt and Yount, were able to step it up when they got the majors, presumably without steroids. But again, look at how young they were when they made it. They were something special and they were rushed along.

It’s interesting to see where some of the other names fall on this list. An argument can be made that some went on to flourish in the majors because of steroids…

The Bottom of the List

And now, the lowest rankings I came up with. I haven’t run all the numbers in baseball history, so I’m sure there are lower results out there.

Some of these guys were highly touted amateurs who just plain sucked. Some of them were victims of being rushed (Trammell, maybe others). But given how much a few of these guys improved in the majors, a case can be made that some of these guys also used steroids…