SPAM - NCAA Football 2021 - Week 8 - IDLE, Week 7 Recap



It's time to face an uncomfortable truth. I have been the soothsayer this year, warning you that as the influence of Iowa's 2020 numbers drop out of the analysis, and the 2021 team stands on its own performance, Iowa's projected fate this year has been steadily declining. It took precipitous dives both last week and now this week. I take no pleasure in being right, and I take even less pleasure in telling you that the prognostication remains grim.

Let's talk about Iowa's offense. We've been saying all year that Iowa's offensive numbers look bad because Iowa turns its opponents over so much, and plays the defense + field position game so well, that Iowa has had unusually short fields to work with. In other words, the yards just aren't there to gain. To test that, I compared Iowa's average field position to that of Indiana and Iowa State in those games, and the theory sure seemed to check out at first. Iowa's field position was remarkably better. So, I decided to see how Iowa compares to the rest of NCAA football.

The results surprised me.

Here's what I did. I found play-by-play data extracted from ESPN's open API. The data is probably a little imperfect but I think it's close enough to work with. Next, I wrote a Perl script that checks for every change of possession, which covers kickoffs, punts, fumbles recovered by the defense, and interceptions. The data also shows the field position where each team gets the ball at the beginning of those possessions. For example, on a touchback, Iowa has the ball at its own 25.

From there, I can calculate how many "potential" or "available" yards there are on each drive. On a touchback, if you punch in a touchdown, you gained 75 net yards of offense. If you kick a field goal from the opposing 25, you only gained 50 out of 75 possible yards. If you turn the ball over on 1st down, you gained 0.

I then calculated how many total yards were available during the game to each team based on its starting field position for each drive, and compared that to how many yards the offense actually gained in that game. You can then calculate what percentage of possible yards were gained. If a team scores a touchdown on every drive, they gain 100%. If they never gain any yardage, they gain 0%.

I'm calling this ratio the Sustainability Index, in honor of the cawing over how Iowa's playstyle is not sustainable, and because it's basically a measure of how well your team can sustain and finish drives. A low ratio means your offense is bad at it, and a high ratio means your offense is good at it. This holds regardless of playstyle, turnovers, etc..

My thesis is that if Iowa's Sustainability Index is reasonable, then Iowa's low yardage totals are indeed a function of playstyle, turnovers, etc., and the dunking all over Iowa's offense that we see is unfair.

There are some limitations to this type of analysis. First, it does not account for situational decisions to not pursue available yards. For example, if your defense gets a big stop and gets the ball back at its own 9 yard line with 12 seconds to play in the 1st half, you're just going to kneel it out, and you get 0 of those 88 yards. I may in the future modify the script to look for kneel-downs and remove those potential yards from the totals, but as you'll see, I don't think it impacts the analysis much.

Second, this also doesn't fully account for offensive penalties. For example, a holding call adds 10 more yards, meaning that if you finish the drive anyway, you could accumulate 85 yards of offense on a 75 yard field. It's theoretically possible to gain more than 100% of the available yards. But, again, I don't think this impacts the analysis much.

So what is the analysis? Here are my findings.

First, the average FBS drive this year began just past the team's own 30, leaving 69.7 available yards. Further, coming into this week, the average FBS team has as Sustainability Index of 46.7%, meaning that a typical FBS team gains 46.7% of the yards available to them over the course of a game (again, regardless of field position).

Coming into this past weekend vs. Purdue, Iowa was #1 in FBS in average field position, having an average starting field position of their own 40, leaving only 60 available yards per drive. This was significantly better than the second place team, Army, who faced an average of 62 available yards per drive.

At first, this seems to validate the Iowa Fan Narrative of "short field = LOLfense," but not so fast. Iowa was also #4 in all of FBS in total possessions with 88. The average FBS team had only 72 total possessions. Those extra possessions are due to the Iowa's turnover rate, and when you get more possessions, you have more total available yards to gain. Thus, although Iowa's shorter fields offset how much is available to gain, each turnover still adds net more yards to the total.

As a result, whereas the average FBS team had 4,963 total yards available to gain so far this year, Iowa has had more than average, at 5,278 total yards available. And, whereas the average FBS team has gained 46.7% of those available yards during the game, Iowa has gained just 36.0%.

That 36.0% number is far, far outside the range of even average. In fact, it's the lowest I could find by a wide, wide margin. Among Top 10 teams coming into this week, it was the lowest by far. The second-lowest was, interestingly enough, Penn State, at 42%. No other Top 10 team coming into last weekend was below 50%. Cincinnati was closest at 50.5%, but the rest all well above 50%. They are: ORE 52.%, BAMA 61.5%, MICH 57.0%, OK 59.7%, GA 53.4%, MSU 57.0%, and Ohio State leads the pack with an astounding 66.8%.

And it's not just playstyle. I also compared Iowa to other teams who have had short fields throughout the year, such as Army, who is #2 behind Iowa in best field position. But the Black Knights have only had 3,300 available yards, compared to Iowa's almost 5,300, and Army had gained 58.8% of them. I compared Iowa's Sustainability Index to the rest of the top 10 teams in starting field position, and Iowa is dead last at 36.0%, again by a very wide margin. None of the others were even below 40%. The closest is Rutgers, at 41.3%.

The conclusion that this Iowa offense is historically bad, even adjusting for Iowa's playstyle, defense, turnovers, and field position advantage, is unavoidable. The awfulness has been hidden in just one place: total points. This is what the turnovers and field position advantage have bee able to do: hide these deficiencies with pick-sixes and some VERY short fields to allow quick scores. But, Iowa just plain cannot move the ball consistently on offense. Every statistical analysis I've seen of this offense confirms this conclusion. And, when you can't turn the other team over, you get what we saw against Purdue.

Iowa's offensive futility is also showing up in SPAM's numbers, which I'll discuss below. But, here's a telling data point. In week 0, Iowa was favored to beat Nebraska by 10.0 points in SPAM's math. By week 2, it had dropped to 8.9 points. In week 4, 7.5 points. Week 6, 4.9 points. And now, in week 8, Nebraska is favored by 1.5 points.

The offense doesn't have to be amazing, but it does need to be somewhere around at least 60th-80th. We're going the wrong way.

On the predictions, SPAM's predictions have been God-awful and I just don't have the morale to track them anymore. If anybody really wants to see how SPAM picks the Big 10, let me know, otherwise, I'm just going to focus on Iowa for the rest of the season.


Here's the updated SPAM projections for the rest of Iowa's season based on the season to date.

Game by Game

Opponent Margin Win%
Indiana 8.3 W (1-0)
@Iowa State -3.9 W (2-0)
Kent State 12.1 W (3-0)
Colorado State 11.5 W (4-0)
@Maryland 7.9 W (5-0)
Penn State 5.1 W (6-0)
Purdue 7.3 L (6-1)
@Wisconsin 1.3 56.1%
@Northwestern 3.1 60.2%
Minnesota 8.9 72.0%
Illinois 12.4 78.2%
@Nebraska -1.5 43.4%

The Hawkeyes are mortal. There's not much more to say.

Record Projection

Record Odds
7-5 5.9%
8-4 21.4%
9-3 35.7%
10-2 28.1%
11-1 8.3%
12-0 n/a

I cannot overstate how devastating that Purdue loss was to Iowa's projections, because it was a game that, in virtually every SPAM scenario, was a win. With it shifting to a loss, it changes everything. Last week, SPAM didn't even calculate the possibility of 6-6. It's on the table now (less than 1%, so I left it off the chart, but still). Last week, there was a mere 7.6% chance that Iowa goes 8-4. Now? 21.4%.

I'm just going to say it, folks. I don't see this team going 9-3. I don't want to overreact to 1 loss, and it was Purdue, who just has Iowa's number. But, I've been watching these numbers trend down week after week when I do this analysis and prepare these posts, and I've had a growing sense of dread about the team's fortunes. If any opponent can just play clean football, they should be able to beat Iowa at it's own game. You know who is good at beating Iowa at it's own game?

Wisconsin and Northwestern. The Hawkeyes are an appalling 2-8 against those two teams over the last 5 seasons. Minnesota wants to beat Iowa at its own game and hasn't been able to, but the Gilded Rodents are bringing a top 30 defense into Kinnick Stadium this year. Yikes.

On the flip side, Iowa is 15-0 over the last 5 years against Illinois, Nebraska, and Minnesota. Nebraska also has an uncanny ability to snatch defeat from the jaws of victory, but if they manage to play an even sort-of clean game, they could finally notch that long-overdue cathartic beatdown of Iowa that they so badly want.

What I'm saying is that the margin for error here is basically zero. If you weren't puckering yet, it's time to start.

Division Championship Odds

Big 10 West

Team Champ. Odds
Iowa 55.8%
Minnesota 20.12
Wisconsin 7.1%
Purdue 5.5%
Northwestern 3.0%
Illinois 0.2%
Nebraska 0.04%

The Purdue loss dropped Iowa from a nearly 90% favorite to win the West, to barely a coin flip. That loss gave Minnesota and Wisconsin the help they needed, and now a heads-up win by either team moves them ahead of Iowa in the standings. It would then be the Hawkeyes who need help elsewhere. Minnesota's future opponents are Maryland, Northwestern, Illinois, Indiana, and Wisconsin. Wisconsin's schedule has Purdue, Rutgers, Northwestern, Nebraska, and Minnesota. Not a murderer's row either way. But, Wisconsin and Purdue have to play each other, as to Wisconsin and Minnesota. Somebody has to win those games.

Finally, with its loss to Minnesota, the Cornhuskers have dug themselves such a deep hole, requiring so much unlikely help elsewhere, that winning the Division is almost impossible. I can't even explain Nebraska football. It's simply unfathomable that a team with that much talent manages to continue to lose games the way that they do.

Big 10 East

Team Champ. Odds
Michigan State 45.6%
Ohio State 34.2%
Michigan 10.2%
Penn State 3.5%

Let's be candid, this is a 4-horse race right now and Penn State is on the outside looking in. Remarkably, Michigan State is, at long last, getting the love heretofore denied it by SPAM. With its win over Indiana, SPAM now projects Michigan State as the front-runner to win the East, with Ohio State a distant second. This is due in significant part to this week being 8, which is the point at which SPAM does not blend in any data from last season, so none of the stink of 2020 Michigan State is on these numbers.

Unless otherwise expressly indicated by BHGP editors, this FanPost is strictly the viewpoint of the author and is not endorsed by BHGP in any way.