Monday, July 28, 2014

Who are the CFL's most successful runners?

Anyone who's watched a football game can tell you that not all yards are created equally.  QBs pile up yardage in failed comeback attempts, and running backs rack up the carries while teams protect a lead.  They might look the same on the score sheet at the end of the day, but there is a significant difference between an 8 yard gain on 2nd and 5, and an 8 yard gain on 2nd and 15.

Success Rate

Success rate is a simple metric that attempts to put a number on the difference between those plays - one of those plays is a successful one (it gained a first down), the other is not.

Your definition of success may differ from mine, but I've opted to define a successful running play as follows:

1) On first down, it gained at least 50% of the needed yards.
2) On second or third down, it gained 100% of the needed yards.
3) The runner did not fumble on the play.

In other words, a 5 yards on 1st and 10 is successful, but 5 yards on 2nd and 10 is not, and neither is a 15 yard run on 1st and 10 where the runner fumbled after gaining the yardage.  Possession of the fumble is not relevant, any fumble, recovered by the offense or not, is considered to be an unsuccessful play.  (Ask any coach and I think you'd find they agree.)

Success rate is shown as a percentage (successes / total attempts).  A rusher with a high yardage total and low success rate probably tends to have long runs mixed with frequent stops for short or no yardage.  A rusher with a low yardage total and high success rate is getting just enough to be successful, and not much more (perhaps indicative of a goal line QB or full back).

2014 Success Rates through Week 5

Through week 5 I've limited this list to running backs with at least 15 carries, and quarterbacks to those with at least 5 carries.  I will increase these value as the season goes on.
Success Rate - Running Backs (min 15 attempts)

Success Rate - Quarterbacks (min 5 attempts)
By itself, Success Rate doesn't tell the whole story about a runner (would anyone rather have Pat White's 100% success rate and 1.7 YPC than Tanner Marsh's 88% and 6.4 YPC?), but it does provide an interesting metric to add to the conversation.

2013 Success Rates

I intend to put up a page on cflstats.ca to display success rates for all seasons, but in the meantime, here are the values for last year.
Success Rate - Running Backs (minimum 50 attempts)

Success Rate - Quarterbacks (minimum 15 attempts)

3 comments:

  1. Very nice post - it's disheartening to see Nic Grisby so low. Granted, it's early but a cause for concern IMHO.

    One error I noticed however - Drew Willy played for Saskatchewan last year, not Winnipeg.

    Great site - keep up the good work!

    ReplyDelete
    Replies
    1. Thanks for the feedback, Monty.

      Looks like there was an error in my query to generate the 2013 tables that pulled the most recent team, instead of the most recent team in 2013. Oops, good catch!

      Mike

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  2. What an amazing blog you run! Keep it up.

    ReplyDelete