There’s a lot of talk about the Eagles potentially trading up for a WR, or at least taking one with their 1st round pick. Peter King has them giving up their 1st and 2nd round pick to get Odell Beckham Jr. I’ve been very clear about why I think this is a poor strategy (trading UP for a WR is an unbelievably bad decision). For more on those reasons, see my last post. Today, though, I wanted to look at it from a different angle and discuss things in light of what the actual WR class looks like. Previously, I left it at "it’s deep", which doesn’t really provide the full context.
From my TPR rankings, here are the top 10 WRs in the draft. Remember, since these guys each play the same position and I took individual standard deviation out of the formula, these relative rankings are primarily the result of the NFL.com, ESPN, and NFP grades. The multiplier stratifies the class a bit, but the effect is small.
We can ignore Sammy Watkins and Mike Evans. I’m sure Chip would love to grab Evans, but it’s extremely unlikely he falls out of the first 10 picks.
Instead, let’s focus on the second tier, the yellow shaded area. Here we have four WRs that have all, at various points in time, been linked to the Eagles. If the Eagles come out of the 1st round with a WR, it’s nearly a certainty that it’s one of these four guys. But that’s not what we’re here for, is it?
Looks closely at each of those prospects and look at the grade assigned. Now, how certain are you that you can identify which one will be the best NFL player? "Not at all" is the correct answer. I’m sure the Eagles have different grades and a different order of players, but the fundamentals are the same. You need to ask yourself two questions: How big is the difference between each prospect’s grade? How big is the margin of error in our evaluations?
Within each tier, the MOE (if you’re being honest) is almost definitely larger than the difference in grades. Therefore, practically speaking, they all have the same grade. I other words, they all have the same expected value.
So why would you want to pay more for one of them than they other?
Now, let’s take aim at Peter King’s rumor, which is:
Eagles trade up for the 15th pick and select Beckham.
First, let’s see how necessary that trade is. If they complete it, obviously they get Beckham. If not, though, how likely is he to be available at the 22nd pick?
Well it just so happens that Brian Burke of advancedfootballanalytics.com (new name) has just released a Bayesian prediction model for the draft. Obviously, we can’t put too much weight into this just yet, but it’s a very good representation of the type of thinking every team should be doing. Here is Beckham’s output:
According to this model, there is just a 7% chance that Beckham is available at the 22nd pick. There is a 53% chance he is available at the 15th pick. The Eagles would only make the trade if he was actually available at 15, so we don’t have to worry about that second probability. Just note that it’s basically a flag that says: even if the Eagles and Steelers want to make that trade, there’s a 50/50 chance it won’t happen.
So, if the Eagles want Beckham, it looks like they really do need to move up. How about the other guys in that tier?
There is a 51% chance that Marqise Lee will be available at 22.
There is a 21% chance that Brandon Cooks will be there at 22.
There is a 92% chance that Kelvin Benjamin is there at 22.
Now, these aren’t completely independent probabilities, so what I’m about to do isn’t 100% "correct", but it’s not unreasonable either. Combining those probabilities leaves us with a:
.49 * .79 * .08 = .03 or 3% chance that none are available.
So, the Eagles can give up their 2nd round pick for a 100% chance of Beckham, or they can keep their pick and have a 97% chance at one of the other three guys in that same tier.
Now can you see why trading up is such a terrible value? We’ve already covered the margin of error issues. Regardless of which players are in the same tier, conceptually they are all worth the same "value". So if the Eagles tiers looked like mine, they’d essentially be trading a 2nd round pick for a 3% increase in the odds of getting a WR from their desired tier.
That’s also known as a catastrophically bad use of resources.
Now let’s look at it a little differently. Let’s say the Eagles do have Beckham rated significantly higher than the other three guys in that tier. The operative question then becomes: how much higher?
This is important because we have to account for the opportunity cost of the 2nd round pick (which is large). That brings me to the concept of saturation drafting. In short, there’s no rule against using multiple picks in one draft on the same position. For example, let’s say the Eagles have decided they NEED a star WR out of this draft. They can:
A) Do Peter Kings trade, after which their odds of gaining a star WR will be whatever the odds of Beckham becoming one are.
B) They can NOT trade their 2nd round pick, and use it on ANOTHER WR!
To examine this possibility we need to know who will be available in round 2. Let’s move to the next tier on our list. This one:
What are the odds those players are available at the 54th pick?
Davonte Adams - 38%
Jarvis Landry - 62%
Cody Latimer - 8%
Jordan Matthews - 37%
Once again, they’re all in the same tier, and the individual margin of error means they each of roughly the same expected value. Given the odds above, that means there is a:
.62 * .38 * .92 * .63 = .136 that none of those guys are available at 54. Flipped around, that means there is a 86% chance one of those players will be available at 54.
Going back to our two options, that means the Eagles, spending the same amount of draft resources, can have:
100% chance of Beckham
97% chance at a player like Marqise Lee AND an 86% chance at a player like Jordan Matthews.
Now, if you NEEDED a star WR, would you choose option A or B? That ignores a lot of other options (for example, you could trade up in round 2 to give yourself a 100% chance of a 3rd tier WR), but it lays out the conceptual problems with trading up for a WR in round 1.
That’s a very long way of saying what I’ve said before: If you are going to trade up for anyone, ESPECIALLY a WR, you need to be extremely confident he’s much better than the next guy. Realistically, I just don’t see how the Eagles could possibly be that confident.
Therefore, trading up for a WR is a very poor strategic decision. Remember, you’re not picking players, you’re picking lottery tickets. Each one carries a different likelihood of "hitting", but they all have risk of busting. All you’re trying to do is maximize your odds.
The Eagles rankings undoubtedly look different from the tiers I’ve used above, but it really doesn’t matter what names you put in which tier. Unless the Eagles think the gap between Beckham (or whomever) is EXTREMELY LARGE, trading up doesn’t make any sense.
Lastly, I’ll leave you with some spider graphs (from mockdraftable.com):