Is Cassel Regressing?

Plenty of people thought Matt Cassel sucked before, but after the Chargers games the calls for him to be benched have reached a fever pitch. I've heard several times that Cassel has actually regressed from previous seasons to the point where we would be better off with almost anybody else at QB.

But is this regression real, or just a statistical fluke. Human beings are notoriously bad at intuitively understanding statistics without studying it, so it's entirely possible that people are overreacting to statistical noise. Luckily, there are ways of calculating this kind of thing.

First of all, we need to establish a baseline. We have to know how Cassel usually plays to understand if he's playing worse than normal. We'll be using four main stats here, ones that are by far more important than any other in terms of evaluating QB's. They are net yards per attempt, yards per attempt, interception percentage, and completion percentage. These stats should give us a good idea of any change in Cassel's performance.

Cassel Career: 5.7 NY/A, 6.6 Y/A, 2.7% interception rate, 58.9% completion percentage

Cassel 2012: 5.7 NY/A, 6.6 Y/A, 4.3% interception rate, 58.4% completion percentage

So, when comparing the stats, he's having a typical season in every way except interception percentage. If he's regressing, then his regression is coming only in that category.

But is his increased interception rate due to a real decline in skill or statistical noise. This is impossible to answer for sure, since anything is technically possible, but we can still determine how likely it is for him to throw more than 6 interceptions on 161 attempts assuming he throws an interception 2.7% of the time.

Doing this is really not that difficult. This kind of thing is described by a binomial distribution, so by just plugging some numbers into my calculator I found that there's a 14.8% chance of throwing more than 6 interceptions on that many attempts if his "real" interception rate is 2.7%.

So what does that mean? At the very least, it means that it's realistically possibly for that kind of divergence to happen. For 32 NFL quarterbacks, that comes out to about 4 or 5 of them having a similar statistical fluke in their interception number. In fact, I'd argue that Cassel already experienced one of those flukes before in his career in 2010, except that year his fluky interception rate was fluky in a good way.

The more important question is what we should expect from this season if his interception rate does go back to normal. Do we have any hope of having a good season?

The surprising answer is yes, we actually are not in a terribly spot. In my previous post I detailed how the Chiefs are only the 5th team in NFL history to have a -10 or worse turnover margin while outgaining their opponents by more than 300 yards through the first 4 weeks. All four of the previous teams had a winning record after week 4, although the two who had a losing record after 4 games didn't make the playoffs that year (but they both won a playoff game the following season, including one who won the Super Bowl). The other two teams were 2-2 (and made the playoffs) and 3-0-1 (and won the Super Bowl), so they were in a bit better shape than we are.

But there's a fairly recent team who started 1-3, had mediocre QB play, and went on to win the Super Bowl. Here was that QB's stats compared to Cassel's:

Cassel Career: 5.7 NY/A, 6.6 Y/A, 2.7% interception rate, 58.9% completion percentage

Super Bowl Winner: 5.8 NY/A, 6.9 Y/A, 2.9% interception rate, 63.9% completion percentage

Other than the completion percentage, the Super Bowl Winner was almost identical to Cassel in his statistics the season he won the Super Bowl. But really, when the yards per attempt is the same, completion percentage doesn't matter all that much. It just means Cassel is getting more yards out of the passes he is completing.

So who is this QB? It was none other than Tom Brady when he won his first Super Bowl in 2001. Many people don't realize this, but Brady was basically a Cassel clone until 2004, winning two Super Bowls before he really started playing like the elite QB he is today. In fact, the 2003 team started 2-2, including a 31-0 loss at Buffalo in week 1.

Here are Brady's two most recent Super Bowl winning seasons. One looks like Cassel, the other looks like the modern Brady.

Brady 2003: 6.1 NY/A, 6.9 Y/A, 2.3% interception rate, 60.2% completion percentage

Brady 2004: 7.1 NY/A, 7.8 Y/A, 3.0% interception rate, 60.8% completion percentage

In short, while it's certainly not preferable to try and win the Super Bowl with a mediocre QB and starting the season 1-3, it isn't impossible.

This is a FanPost and does not necessarily reflect the views of Arrowhead Pride's writers or editors. It does reflect the views of this particular fan though, which is as important as the views of Arrowhead Pride writers or editors.

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