This article is intended to be a very ‘back of the envelope’ way to calculate values for MiLB players and should be used as a framework  toward better understanding what prospects are worth in dynasty leagues. 

Owning MiLB players in a Dynasty League team can be one of the most rewarding as well as frustrating components of a deep league. These players have the ability to pay off extremely handsomely, i.e. Mike Trout, but more often than not they usually land somewhere on the scale of usable player to completely worthless, i.e. Rocco Baldelli/Brandon Wood. And from these varying extreme possibilities lies the difficulty in valuing MiLB players against MLB guys. So to help in valuing these types of players against each other I’ve put together an easy way to approximate MiLB worth no matter what league you play in.

Much of this valuation method works directly from the results of a post Scott McKinney wrote on Royalsreview.com that determines Success and Failure Rates of Top MLB Prospects. From Scott’s work we can easily see that the majority of top 100 prospects end up being busts rather than even moderate successes. In fact Scott has determined that 69.2% of all Baseball America rated top 100 prospects go on to be busts. 69.2%. Prospecting is definitely a tricky game. However, I’m not going to go out and tell you to immediately sell off all your prospects, and especially not the higher ranked ones, as Scott also shows us that higher ranked prospects have much better rates of success in the majors with a bust rate of just 47.5% for any player ranked in the top 20..

Using these and the other prospect success percentages provided in the article we can easily start to form an idea of what type of risk these prospects carry with them and in turn use that to estimate value. Let’s jump into an example.

Lets say we have two prospects, one who is ranked 15th overall and one who is ranked 35th overall. The 15th ranked prospect has a 50% chance of being a success while the 35th ranked prospect only has a 30% chance of success. Using these two probabilities we can do a couple things, first we can determine that the chance of both players becoming successes, (.5 x . 3) = .15, is 15%, secondly we can determine what the chance of at least one of the players becoming a success is ((.5 + .3) – .15) = .65, 65%. So for the these two players we have a 15% chance of them both realizing success and a 65% chance of at least one of them making a worthwhile impact.

To make things easy in our valuation let’s assume neither prospect contributes in 2014 and that they both will be 23 years old for the 2015 season. Using the standard MLB aging curve we see that most players reach their peaks between 26-29, so from 2015 through 2019 (i.e. ages 23-27) our prospects will slowly be gaining value and then plateau during their peak years. If we assume our prospects have peak values of $30 and $25 respectively then we can guesstimate that if all goes according to plan our prospects will be worth a total possible value of $215 over the next five years, see the table below for a breakdown of that value.

However, we know from above that we only have a 15% chance of this type of value happening.  We also know we have a 65% chance that at least one of our prospects succeeds.

Now let’s say for example a trade was proposed including these two prospects for an older player like Robinson Cano, and in this league Cano has a projected value of $30 for 2014. Applying a basic MLB aging curve to Cano’s value shows us that he should lose approximately 5-10% of his value each year for the next six years, for our sake let’s say a 10% loss.

Ok, so now we know over the next six years our ‘surer’ bet should produce $135 dollars and our prospect bet will produce somewhere between $0-215.

Let’s assume Cano has a 85% chance to hit is projected value and use our probabilities from our prospects achieving their projections from above to calculate the average value of the deal.

Possible Outcomes

85% x $135 = $114.75 (Cano probability multiplied times value)

50% x $120 = $60 (15th Prospect Probability multiplied times value)

30% x $90 = $28.5 (30th Prospect Probability multipled times value)

So the sum of Cano minus our prospects equals our average value or 114.75 – (60 + 28.5)  = $26.25 meaning that the person getting the Cano side of the trade is expected to profit $26.25 on average when making this trade.

Keep in mind that this value has been calculated for ONLY the next six years. Obviously at the six year point our two prospects should be in their primes and Cano should be inching toward retirement, however, I wanted to limit this example to six years as our ability to project anything with confidence after that length of time will basically be zero and six years gives us a pretty solid understanding of value to start with. It also should be noted that as much as prospects can provide a ton of value over the long haul when trading them for stars an owner should be aware that a significant amount of time for our prospects to even come close to matching the star players value.

I tweet about Baseball/Digital/Funny things @lukechatelain, feel free to hit me up with comments, questions or jabs about my lesser intellect.