A Closer Look at Cleveland's Pass Defense

A few readers have pointed out that Cleveland's pass defense is rated so high because they have played against Joe Flacco, Ryan Fitzpatrick, and a game in a driving wind storm.

This gives us a great opportunity for a long column, because it points out:
1) I haven't explained True Player Value (TPV) very well
2) There are some flaws with TPV that need to be considered

OK, first, the Flacco issue. The purpose of True Player Value is to evaluate the performance of players and defenses based upon the strength of the opponents that they faced. A full series of explanations on how we calculate that is here.

Since Flacco is obviously a below-average QB, he would be expected to have below-average yardage against an average pass defense. A bad pass defense would allow him to give up average or greater yardage, and a good pass defense should allow him very few yards. The True Player Value algorithm currently defines "Average" as 222 yards passing per game.

Flacco's TPV for passing yardage is -6%, meaning you would expect Flacco to throw for 209 yards against an average defense. His real-life numbers are actually worse because he has played against above-average pass defenses in the Bengals, Browns, Steelers, and Titans.

Bengals? Bengals!? BENGALS!!?? That's right, the Bengals have an above-average pass defense in terms of TPV. Remember, TPV is only concerned with how many passing yards a player will accrue against a defense, not how good the actual defense is. Since the Bengal's run defense is so bad, and their offense to date has been so pathetic, there has been no need to pass against them. Thus, you can't discredit Flacco too much for not passing often as the Ravens beat the Bengals by running for 229 yards. I don't care if your QB is Joe Flacco or Joe MONTANA - if you can run for over 200 yards against a defense, you won't be passing much.

Back to Flacco against the Browns. He had 129 yards passing in that game. In other games, he has passed for 129, 153, 192, and 241 yards. So the Browns do deserve some credit for holding a mediocre QB to his lowest output of the season.

Of course, the whole argument for the Bengals pass defense kind of applies to the Browns as well. Since they have been behind in 3 out of 5 games, teams haven't had to pass on them as much. But teams that needed to pass on them, like the Giants this past Monday, ran into some problems as well.

The next point, Ryan Fitzpatrick, is a far better argument against the Browns passing defense, and does point out a flaw in TPV. When developing the TPV value for the Browns defense, it used the Bengals pass offense value to come up with a number as opposed to Fitzpatrick's TPV value. So, the Bengals replaced Palmer with an inferior QB, but the Browns defense was still credited with playing against Palmer (or actually some evil 2/3 Palmer, 1/3 Fitzpatrick hybrid). So let's try to figure out, from Fitzpatrick's TPV, how the Browns defense really fared in that game.

The Bengals pass offense (including Palmer's games) has a yardage value of -19%, which makes the 156 yards given up by the Browns translate to 193 yards. Ryan Fitzpatrick has a passing yardage TPV value of -24%, making the performance translate to 205 yards. But there is a sample size problem here. Since half of Fitzpatrick's starts are against the Browns, and the Browns have a good passing yardage defense TPV, then Fitzpatrick's TPV could be artificially high, even at -24%. Indeed, if we look at his one other game, against the Jets, he had only 152 yards passing. The Jets are a +1.3% passing yardage defense, meaning an average QB should have 225 yards passing against them. Fitz's performance garnered a TPV value of -32%. If we use this as Fitzpatrick's base value against the Browns, his 156 yards passing balloon up to 217 yards that the Browns would have given up, if the Bengals only had a league average QB.

The wind game points out another potential flaw with TPV. If weather conditions are extremely bad for one game, then defenses will obviously be rated higher for that game than they really should be. We can only hope that the sample size of all the games we take into consideration is large enough to make this effect minimal.

In the wind game, the Steelers (+2.9% passing yards offense) had 186 yards, which translates to 181 TPV yards for the Browns. In other games, the Steelers offense has managed 137, 191, 191, and 309 yards. If we remove the wind game from consideration from the Steeler's offense, their TPV per-game average becomes 228 yards, or +3%. Surprisingly, the wind game did not really hurt the Steeler's pass offense ratings.

So, let's take all this into consideration and re-calculate the Browns defensive pass yardage TPV. We will adjust Fitzpatrick's TPV yards from 193 to 217 (in between where TPV says he is and where the 1 game against the Jets says he is), and throw out the wind game altogether.

Here is the actual yardage and the TPV yardage given up in each game by the Browns this year:

Opponent	Actual Yardage	TPV Yardage
Cowboys	320	215
Ravens	129	137
Bengals	156	217
Giants	196	156

So the average TPV performance in these four games is 181 yards allowed, which ironically is exactly the TPV performance of the wind game that we threw out. This gives the Browns a -18% TPV, which is almost exactly what the TPV algorithm had originally told us (-21%).

I had started this article assuming that some flaws were pointed out in TPV (and I still believe they were), and that I would have to adjust the Browns passing defense TPV (and thus the Redskins projections for this weekend) accordingly. But, this analysis shows that the sample size were are using at this point in the season is large enough to hide these flaws, and I should not change my projections, which predict a very pedestrian 156 yards passing for Jason Campbell.

And now that I have written that, Campbell is gaurenteed to go off for 300 yards this weekend...