2020 Yards Per Play: Mountain West

This week, we follow Horace Greeley's advice and go west.   

Here are the 2020 Mountain West standings.

So we know what each team achieved, but how did they perform? To answer that, here are the Yards Per Play (YPP), Yards Per Play Allowed (YPA) and Net Yards Per Play (Net) numbers for each Mountain West team. This includes conference play only, with the championship game not included. The teams are sorted by Net YPP with conference rank in parentheses.

College football teams play either eight or nine conference games (typically fewer in 2020). Consequently, their record in such a small sample may not be indicative of their quality of play. A few fortuitous bounces here or there can be the difference between another ho-hum campaign or a special season. Randomness and other factors outside of our perception play a role in determining the standings. It would be fantastic if college football teams played 100 or even 1000 games. Then we could have a better idea about which teams were really the best. Alas, players would miss too much class time, their bodies would be battered beyond recognition, and I would never leave the couch. As it is, we have to make do with the handful of games teams do play. In those games, we can learn a lot from a team’s YPP. Since 2005, I have collected YPP data for every conference. I use conference games only because teams play such divergent non-conference schedules and the teams within a conference tend to be of similar quality. By running a regression analysis between a team’s Net YPP (the difference between their Yards Per Play and Yards Per Play Allowed) and their conference winning percentage, we can see if Net YPP is a decent predictor of a team’s record. Spoiler alert. It is. For the statistically inclined, the correlation coefficient between a team’s Net YPP in conference play and their conference record is around .66. Since Net YPP is a solid predictor of a team’s conference record, we can use it to identify which teams had a significant disparity between their conference record as predicted by Net YPP and their actual conference record. I used a difference of .200 between predicted and actual winning percentage as the threshold for ‘significant’. Why .200? It is a little arbitrary, but .200 corresponds to a difference of 1.6 games over an eight game conference schedule and 1.8 games over a nine game one. Over or under-performing by more than a game and a half in a small sample seems significant to me. In the 2020 season, which teams in the Mountain West met this threshold? Here are Mountain West teams sorted by performance over what would be expected from their Net YPP numbers.

Colorado State and Wyoming were the only Mountain West teams to see their actual record differ significantly from their expected record based on YPP. Both the Rams and Cowboys underachieved. Colorado State had meltdowns on special teams, allowing five such touchdowns in their last two games. This turned a probable loss against Boise State into a blowout and a toss-up game with San Diego State into a loss. For Wyoming, the culprit was close game luck. The Cowboys finished 0-3 in one-score games, losing in overtime to Nevada, by one point to New Mexico, and in a blizzard to Boise State. 

Services Academies Against the Spread

Conventional wisdom holds that service academies (Air Force, Army, and Navy) perform well against the spread (ATS) as underdogs, particularly as large underdogs, and not so well as favorites (especially large favorites). The logic behind that assumption is solid. Service academies run unique offenses that are difficult to prepare for and those offenses tend to depress the number of possessions in a game which leads to increased variance. Theoretically, variance would reward underdogs as less variance would lead to a more 'true' result. Is this conventional wisdom accurate or just another well known fact that is disproven by data? All three service academies have long-tenured coaches so we have a relatively large sample of them in different ATS roles. Let's dive into the data and see what it tells us.

Since this is the Mountain West recap, Air Force comes first alphabetically, and Troy Calhoun is the longest-tenured head coach at a service academy, we'll begin with the Falcons. Here is how the Falcons have performed ATS against FBS opponents in all non-bowl games as a favorite and underdog under Calhoun. 

Conventional wisdom jumps to an early lead. The Falcons have covered just 44% of the time as a favorite under Calhoun, but over 58% of the time as an underdog. What about Army under Jeff Monken?

Monken has been at Army seven years, which represents only half of Calhoun's time at Air Force, but is still enough time to begin to develop a track record. Army's cover record as a favorite under Monken is nearly identical to Air Force's under Calhoun (44%). They have been less successful than Air Force as an underdog, but have still performed much better in that role versus as a favorite. Finally, let's check in on Navy under Ken Niumatalolo. 

It's eerie how similar the three service academies have performed as favorites. At 45% under Niumatalolo, Navy has done just a smidge better than Air Force and Army. As an underdog, they have covered more than 60% of the time. Cumulatively, the service academies have covered slightly more than 44% of the time as favorites and nearly 58% of the time as underdogs under their current head coaches.

So conventional wisdom seems to hold. However, we were interested in how these teams perform as big favorites or underdogs. Let's look at how the service academies have done as both double-digit favorites and double-digit underdogs. Once again, we'll start with Air Force.

The Falcons are worse as double-digit favorites (40%) than they were as favorites of any size (44%), but they are also worse as double-digit underdogs (55%) than they were as an underdog overall (58%). Does the trend hold for Army?

In a small sample (ten games), the Black Knights are better as a double-digit favorite (50%) than they were as a favorite of any size (44%). Their record as a double-digit underdog (50%), was basically indistinguishable from their record as an underdog of any size (51%). And finally, Navy. 

Like Army, the Midshipmen were slightly better as a double-digit favorite (48%) than they were as a favorite of any size (45%). And like Air Force, they were worse as a double-digit underdog (55%) than they were as an underdog overall (60%). Here is how the service academies stack up cumulatively. 

For the most part, the conventional wisdom holds. It's a long-term losing proposition to back a service academy as a favorite, be it double-digit or otherwise. Conversely, backing a service academy in the underdog role is a long-term winning strategy. However, at least under their current administrations, you'd be better off taking them as smaller underdogs. Don't be bashful just because they aren't catching double-digits.