The Stats Room: Projecting Rookies Within Team Context

Previously, I just projected rookie running by going off an average production level. There didn't seem to be any measurable production differences between early and late picks.

One item that really bothered me about this analysis was team context. The rookie running backs who got the most work were likely on teams who needed their help. These teams were bad and the running back's production likely suffered from a bad supporting cast. I was looking for a way to add some overall team context and I may have found an answer in Las Vegas.

For years, fans have been able to bet the over/under on a team's wins. SportsOddsHistory.com collected all the preseason expectations from 2001 to 2017. While not a perfect proxy for team talent, it's a starting point. And I have 17 years of data to match up.

I decided to group the preseason odds into three groups:

1. More than nine wins
2. Seven to nine wins
3. Fewer than seven wins

The seven-to-nine group is the average team projection while the other two are seen as better or worse than average. By using the three groupings, a distinct separation can be seen. I'll start with the rookie running backs.

Running Backs

For running backs, I split them by backs drafted in the first three rounds and then those drafted later. These two groups then got divided into the three win categories. Here are the results.

Note: I used rookies drafted in the first 96 picks (32 x 3) to represent the first three rounds.

• The bad-team running backs were taken earlier in the drafts and performed worse. Of the backs taken in the first three rounds, the ones taken by projected winning teams had a distinctive advantage in yards per carry.

• The backs drafted early by bad teams had similar yards per carry compared to backs drafted by winning teams more than 120 rounds later.

• As previously researched, the backs drafted earlier are better receivers with higher completion rates and yards per completion.

Wide Receivers

With wide receivers, I divided the results into the same six groups and here are the results.

For running backs, it's +/- 0.2 yards per carry likely based on the offensive line.

For wide receivers, their catch rate can vary +/- 5 percent.

Additionally, these projections help to cap expectations on certain players. In the confusing world of rookie projections, hopefully, this provides some guidance.

For reference, here are the projections for the top-25 rookies being drafted at FanTrax. The assumptions are:

• Running backs: Total yards and touchdowns projected from 250 carries and 40 targets

• Wide receiver: Receiving yards and touchdowns projected from 120 targets

• Quarterbacks: Passing yards and touchdowns projected from 500 targets