Defensive Back Consistency in IDP Fantasy Football

Harrison Smith helps your fantasy teams live on the edge of glory, as he was the most consistent defensive back in 2014.

Consistency is overrated.

There, I said it: consistency is a way overhyped idea, and the idea that you will know what to expect sounds, well, almost boring. Don’t you like to be surprised on your birthday? Don’t you want a little uncertainty when your favorite sports teams are playing, so that it’s exciting? Isn’t half of the fun of riding a roller coaster the visceral fear of bodily harm? All of that goes away with total consistency.

This is at least what I’m lying to myself and saying as consolation, because defensive backs in Individual Defensive Player (IDP) fantasy football are notoriously inconsistent. Especially in big-play scoring, where interceptions reign supreme, the defensive back is a shaky monster on a week-to-week basis.

A little uncertainty makes for excitement, but we’d like something to rely on as well. This is why we ask: who were the most consistent defensive backs in 2014?

La Vie Boheme

There are quite a few ways to quantify consistency from a statistical standpoint. We’ve examined some of our options in my previous articles this week on defensive line and linebacker consistency. The consensus of our search was this, though: by looking at just one facet of consistency, we miss a lot of things.

If we only use total points or average weekly points, we might miss that a player had a few really poor weeks and a few really big weeks in scoring. While that averages out nicely, that’s not true consistency. If we look just at average weekly points, Tyvon Branch of the Oakland Raiders (now the Chiefs) was the best balanced scoring fantasy defensive back in 2014. If you’ll remember correctly, though, Branch shattered his foot in Week 3 and didn’t play again last season. Suggesting that he was anywhere near the top-50 of fantasy defensive back options is just silly.

Similarly, if we look only at standard deviation (the variability from the average), we tend to neglect players who have high upside and by nature have a greater variation in point potential. Calvin Pryor of the New York Jets had a standard deviation of 1.93 last season; impeccable consistency in his point production. However, Pryor hardly started and contributed three or fewer points in seven out of fifteen weeks. We have to contextualize each of these facets with the others, as all of them can be misleading on their own.

One of these metrics still should bring us both excitement and security, however. Is there a way to tell for sure who the most consistent defensive backs in 2014 were?

The Boys of Summer

I blend a high floor with a high ceiling in my IDP play through a little concept I call the Startable Rate. What we really want to know from players isn’t necessarily how many points they can put up in a week, nor their average, or variability in that score; it’s how often they did those things relative to the other players at their position. Everyone has to start the same amount of those players; you just want to be able to do that better.

This is where the idea of startability comes into play: if a player produced better than a replacement-level player (in most of my leagues, 16 teams and two cornerbacks and safeties each per team means a top-32 ranking by position) in a given week, then they are considered to have been startable that week. Total up their startable weeks and find the percentage of the fifteen active weeks of the fantasy season, and you have a Startable Rate.

The beautiful thing is that this also works with Elite Rate – the percent of times they submitted weekly scores in the top ten percent of starters at their position. We can see exactly how regularly they were able to submit superlative performances in a week with this metric.

To find the best options, I filtered out any players with less than a 50.0% Startable Rate, then organized them by total points. Interestingly enough, this leaves us with exactly 31 defensive backs from last season – nearly a full DB1 and DB2 set in a 16-team league. For comparison, I also included their average weekly score, their standard deviation, and their Elite Rate. Who were our highest-performing defensive backs by startability?

Player Start% Elite% Avg. Weekly SDev
Harrison Smith 73.3% 13.3% 9.4 4.0
Morgan Burnett 73.3% 13.3% 9.2 3.5
T.J. McDonald 66.7% 26.7% 9.0 5.1
Ron Parker 66.7% 6.7% 7.3 3.6
Jonathan Cyprien 66.7% 6.7% 6.9 3.8
E.J. Gaines 66.7% 6.7% 6.6 3.6
Eric Weddle 66.7% 0.0% 7.7 2.9
James Ihedigbo 60.0% 20.0% 9.1 3.8
Rashad Johnson 60.0% 20.0% 8.7 6.1
Charles Woodson 60.0% 13.3% 8.5 3.8
Jason McCourty 60.0% 13.3% 7.5 4.4
Mike Adams 60.0% 6.7% 7.6 4.5
Kemal Ishmael 60.0% 6.7% 7.3 4.5
Corey Graham 60.0% 6.7% 6.4 3.4
Alterraun Verner 60.0% 0.0% 7.7 2.7
Robert Blanton 60.0% 0.0% 6.9 2.6
T.J. Ward 60.0% 0.0% 6.8 3.3
Glover Quin 60.0% 0.0% 6.6 3.5
Tramon Williams 60.0% 0.0% 6.0 2.5
Antoine Bethea 53.3% 20.0% 8.0 5.1
Michael Griffin 53.3% 13.3% 8.3 5.4
Perrish Cox 53.3% 13.3% 6.1 3.6
Reggie Nelson 53.3% 6.7% 7.5 4.4
Malcolm Jenkins 53.3% 6.7% 6.9 3.8
Chris Harris 53.3% 6.7% 6.6 3.7
Kareem Jackson 53.3% 0.0% 6.6 2.6
Antrel Rolle 53.3% 0.0% 6.5 2.0
Buster Skrine 53.3% 0.0% 6.0 3.3
Desmond Trufant 53.3% 0.0% 5.8 2.0
Darius Slay 53.3% 0.0% 5.4 3.3
George Wilson 53.3% 0.0% 5.3 3.8

Harrison Smith
is the cream of the crop for IDP defensive backs from 2014, whether it’s total points or startability in balanced scoring. He and Morgan Burnett both had 73.3% Startable Rates, and identical 13.3% Elite Rates as well. A few other options like T.J. McDonald, James Ihedigbo, Rashad Johnson, and Antoine Bethea had higher Elite Rates than these two, but they were the pinnacle of consistency and startability.

Interestingly, you’ll notice that only two cornerbacks from 2014 were considered top-10 defensive backs by consistency, and one of those -- Ron Parker -- actually played most of his 2014 snaps as a safety. This means that E.J. Gaines was the only hyper-consistent fantasy option in balanced scoring on the perimeter. There are plenty of cornerbacks scattered throughout the bottom part of this table, and knowing which ones are the most consistent in fantasy will help you get values. This just serves as a reminder that the high end of the fantasy secondary spectrum is dominated by safeties, due to high tackle opportunities.

Living on the Edge of Z

Depending on your scoring format, these numbers do change slightly, but balanced scoring does provide a solid basis to work off of. If you have a tackle-heavy or big-play scoring system, here are a few notes of difference.

In tackle-heavy scoring, Burnett (73.3% SR, 13.3% ER) dethrones Smith (66.7% SR, 13.3% ER) as the top consistency option, and outscored every other defensive back by a country mile. Smith’s major sack upside from the safety position is what buoys him to the top in balanced, but Burnett fed on tackle opportunities thanks to Green Bay’s poor linebacker play in 2014. Notable additions to our 50.0% club include Ryan Mundy (66.7% SR, 13.3% ER), Barry Church (60.0% SR, 13.3% ER), and Ha Ha Clinton-Dix (60.0% SR, 0.0% ER), all of whom capitalized on bad linebacking corps last year.

In big-play scoring, Smith returns to glory as the consistency top cat, with an 80.0% Startable Rate, but no elite weeks. In this format, free safeties and big playmakers dominate the top end, so it’s a bit harder for in-the-box safeties to put up elite numbers. To that point, only 25 defensive backs had 50% or greater Startable Rates in big-play scoring; this scoring system allows players to make an impact in more ways than tackle opportunities. The additions to the top-tier in this format include Aqib Talib (53.3% SR, 20.0% ER), Mundy (53.3% SR, 6.7% ER), and Bradley Fletcher (53.3% SR, 6.7% ER).