Reliability in a running back is important. Grinding out yards -- consistently getting positive gains -- and holding onto the ball (talk to Bill Belichick about that) can go a long way.
As most of you know, we use a metric at numberFire called Net Expected Points (NEP), which shows how many points a player performs above or below expectation. There's a difference between a 10-yard gain on 3rd-and-10 versus a 10-yard pickup on 3rd-and-15, after all. One picks up a first down and extends a drive, while the other more than likely results in a punt. Net Expected Points factors all of that into the equation.
Each play on the football field can also be thought about in more of a binary fashion. Success Rate measures this -- if a player has a positive play in terms of NEP, it's deemed a success. If not, it's a failure. The percentage of successful plays a player has, then, gives us a Success Rate.
Because rushing is far less efficient than passing, Success Rates are generally lower at the running back position. Logically, this makes sense -- it's much easier for a receiver to pick up big chunks of yards or make an impactful play through the air than it is a running back doing the same thing on the ground.
Success Rate sort of shows us reliability and dependability. If a player is always putting together positive gains, you would naturally call that player reliable. But note the difference between Success Rate and regular Net Expected Points, or Net Expected Points per play -- Success Rate doesn't tell us the extremes. For instance, a player may pick up a first down on 3rd-and-1 -- a positive play -- but if he runs for only one yard, that's not as huge as an 87-yard scamper.
Make sense? Good. Now let's take a look at the 10 running backs with 150 or more carries last year who ranked highest in the Success Rate department.
| Player | Rushing NEP per Rush | Success Rate |
|---|---|---|
| Jeremy Hill | 0.09 | 48.65% |
| Marshawn Lynch | 0.10 | 48.57% |
| Jamaal Charles | 0.11 | 48.29% |
| Lamar Miller | 0.06 | 47.44% |
| Le'Veon Bell | 0.06 | 47.24% |
| C.J. Anderson | 0.10 | 46.93% |
| DeMarco Murray | 0.03 | 46.68% |
| Matt Forte | 0.01 | 46.62% |
| Mark Ingram | 0.04 | 45.58% |
| Rashad Jennings | 0.00 | 45.51% |
There really shouldn't be a whole lot of surprises here, as the backs listed are mostly big-bodied players who succeeded even through normal statistics. Perhaps the biggest shock comes at the bottom of the list, where Rashad Jennings makes an appearance with a 45.51% rate. Though the Giants brought in Shane Vereen this offseason, a healthy Jennings could be a great player in what could be a great offense in 2015. Jennings, too, is discounted in fantasy football due to age and injury history, which means he could be a nice middle-round pick considering this data.
Oh, and Jeremy Hill is a monster. Don't forget that.