Everyone knows that it’s important to protect the quarterback.  Teams spend millions of dollars on the best offensive linemen in hopes that they will give their quarterback enough time to tear up the opposing secondary.

Since passing is so important in the NFL today, how can we measure the effectiveness of protecting the quarterback?

Sacks and Win Percentage

As a simplistic measure, let’s use sacks as a measure of protecting the quarterback.  Below is a plot of win percentage for every quarterback in the league that’s played at least 4 games versus their average sacks per game:

There seems to be a clear trend that fewer sacks per game improves a team’s chances of winning.  The R-squared value for that trend is 0.29, which isn’t large, but is significant as far as football statistics go.

Sacks and QB-Rating

On the other hand, there is no correlation between sacks per game and quarterback rating:

On the extremes here are Kerry Collins with only 1 sack in 7 games with a 74.2 QB rating and J.T. O’Sullivan with a bone-crushing 29 sacks in 7 games and a 75.5 QB rating.

Using sacks per game may not be the best measure of how well an offensive line protects the quarterback.  I used it here because it’s the easiest to measure. A statistic that incorporates sacks, hurries, and knock-downs would be a better indicator of how well a quarterback is protected.

Quarterbacks Perform Independent of O-Line?

If J.T. O’Sullivan were traded to Tennesee and played behind their offensive line, would he be transformed into a superstar?  I don’t think so.  My guess is that his QB rating would have a slight but negligible increase.

This isn’t a conclusive study, but I think this indicates that a quarterback’s performance is almost entirely independent of their offensive line.  There are a lot of uncontrolled variables here such as the quality of the rest of the offense and the strength of schedule, but I’m not too surprised by this result.

O-Line and Running Backs

What about Frank Gore?  Would his yards per carry increase if he were traded to Tennesee?  I bet it would. Running backs seem to be more interchangeable than quarterbacks and depend more on their offensive line.

Sacks allowed is somehow related to win probability, but perhaps not through quarterback performance.  I’ll look into the effect of offensive line on the running game in a later post.  There is probably a reason that teams invest heavily in offensive lines, and there should be a way to measure how effective that strategy is.

In my last post, I outlined four players on track to break records this year.  In just two short weeks, however, that list was cut down to one:

Drew Brees

Brees is holding steady at 332 yards per game, which will give him 5,315 for the season if he can continue that pace.  But can he?

The Saints have had an easy schedule so far.  He’s already lit-up the league-worst Broncos for 421 yards, and  the toughest pass defense he’s seen so far was Washington, the 13th best in the league.

Adjusting for Strength of Schedule

The graph below shows Brees’ passing yards versus his opponent’s defensive passing rank.  The blue dots show his actual performance in the past six games and the red dots show his predicted performance for the next 10 games.

As you can see, not only has he faced a lot of bad defenses, he’s scheduled to play even more bad defenses including San Diego (31), Detroit (30), and Atlanta twice (24).  He only has three games against above average defenses: Carolina twice (2) and Green Bay (7).

Adjusting his average yards per game for opponent difficulty, he is projected to finish the year with 5,111 yards.  That’s a hair more than Marino’s 5,084 yards in 1984.

Conclusion

Drew Brees has played a cream-puff schedule so far and has a cream-puff schedule ahead of him.

After adjusting for strength of schedule, he is on pace to break Dan Marino’s single-season passing record, but just barely.

Don’t expect a big game from him this week against Carolina, but he will stay within reach of Marino’s record down the stretch.

It’s difficult to know when to sell high on a player. They may continue to perform well or they may just be on a hot streak.

However, when a player is on pace to break an NFL record, that might signal that they will drop off soon.  So far this season, there are four quarterbacks and receivers on track to break single-season records.

The fact that no running backs are at record-setting pace indicates that the league is continuing its new passing trend that I wrote about earlier.

Here are the outstanding passers and receivers so far. The projections below are their per game averages multiplied by 16 games:

Passing Yards

NFL Record: 5,084 (Dan Marino)

Both Brees and Cutler have looked good so far, but there is a good chance they will slow down to less Marino-like paces.

Receiving Yards

NFL Record: 1,848 (Jerry Rice)

Obviously Marshall’s performance is closely tied to Cutler’s above, and they’re both on track for big seasons. However, just one or two bad games will throw them off this pace.

No Running Backs

It’s not surprising that after only four weeks some players are above record-setting pace. What is surprising though is that they are all in the passing game. Running backs are completely absent.

The leading running back in the league is Michael Turner, who has 422 yards through 4 games. That’s only on pace for 1,688 yards, which is well off the record of 2,105 yards.

Sell High or Let It Ride?

Is it time to sell high on Brees, Cutler, Marshall, and Jennings? Or do some of them have a legitimate chance at maintaining their pace?

Perhaps Jay Cutler and Brandon Marshall can knock off the passing and receiving yardage records similar to how Brady and Moss broke the single-season touchdown records last year.

However, if you think they are more likely to slow down, then now is the time to trade them away.

Here’s a look at some key stats from week 3:

Earnest Graham stopped by the Bears

Earnest Graham had averaged 8.3 yards per carry through week 2. Against the Bears, however, he got shut down and averaged a measly 1.3 ypc. He would have done even worse had they not gone into overtime because he had only eight yards on 10 carries through four quarters.

Although Chicago successfully stopped the run, they did leave the door open for Griese to throw for 403 yards and maneuver a win. That may signal to future opponents that they have to respect the Tampa Bay passing game and leave some holes open for Graham.

Unexpected quarterback standouts

Would you have guessed that the top four quarterbacks of week 3 (through Sunday) ranked by QB rating would be:

1. J.T. O’Sullivan (123.3)
2. Matt Ryan (120.6)
3. Chad Pennington (113.8)
4. Jason Campbell (112.2)

[Edit: Philip Rivers had a 130.0 rating against the Jets on Monday night]

Also throw in Ronnie Brown’s perfect 158.3 QB rating against the Patriots, which tops the list of surprising performances this week.

The worst quarterbacking of the week was done by Derek Anderson who put up a 22.9 QB rating. That wasn’t the kind of game he needed to keep Brady Quinn on the bench.

Philly D holds strong

Despite facing Steven Jackson, Marion Barber, and Willie Parker this year, Philadelphia’s rushing defense is the best in the league and has allowed only 45 rushing yards per game and just one rushing TD.

The Eagles face off against the Bears in week 4, and it looks like they will give Matt Forte a tough time. No running back has more than 63 yards against them.

How bad is Detroit?

There are now public calls by the Lions’ Vice Chairman for Matt Millen to leave. Is it really that bad though?

Let’s see… their rushing defense is last in the league allowing 207 yards per game.

Their passing defense is only the 23rd worst in the league, but every quarterback they’ve faced so far is in their first year as a starter (Ryan, Rodgers, O’Sullivan).

The offense has struggled equally with the 4th-worst rushing attack in the league. Also, Kitna leads the league in interceptions (5) and has been sacked the second most in the league (12).

The Lions have a bye this week, but the Bears will be eagerly waiting for them in week 5.

It can be addictive to track live game stats on a Sunday during football season. When you’re in multiple leagues, nearly every play counts for or against you.

While most league hosting websites offer free live stats, Yahoo still charges for them with their StatTracker product.

Fortunately, if you don’t feel like paying for live stats, there is an alternative. It is a Greasemonkey script for Firefox called Yahoo Fantasy Football Free Stats. This is part of a screen shot from my team yesterday using the Free Stats program:

The upside is that it’s free. The downside is that it doesn’t calculate fantasy points. It just displays raw stats. That’s one big advantage StatTracker has. Still, it’s better than clicking on every game score within your team list and searching for their stats.

To use this program, you need Firefox with the Greasemonkey add-on installed. This program is not supported by Yahoo (or Fantasy Football Calculator).

If you’re a Firefox user who has decided not to buy StatTracker, give this program a try. It’s guaranteed to save you time every Sunday.

One of the most valuable articles in Pro Football Prospectus 2008 describes a new way to predict the future performance of rookie running backs.

In “Five Seconds Can Be a Lifetime,” Bill Barnwell describes a simple equation that combines a rookie’s weight and 40-yard dash time into one number that is better than any other number in predicting if that running back will be a success in the NFL.

He calls that number the Speed Score and calculates it with this equation:

The faster a player’s time, the higher the Speed Score. Also, if two players run the exact same 40 time, the one that is heavier gets a higher score because he had to run the time with more weight on his body.

When Barnwell looked at past rookies and how they later performed, he found that many successes had a speed score greater than 100 and many busts had speed scores less than 100.

I don’t want to give away too much, but when you look at the list of players it picked to succeed versus those it didn’t is pretty impressive. It is slightly biased because a 40-yard dash time that isn’t weight adjusted is already a good indicator of success. However, their statistics show that the speed score is slightly better than the 40-time alone.

Can you guess which rookie this year posted the highest speed score at the combine? You’ll have to buy the book to find out, but I will say that it wasn’t McFadden.

For the past eight years, it has been expected that you could draft at least one 300-carry running back for your fantasy team. That’s because there have been approximately ten 300-carry running backs each year since 2000.

Except for last year. In 2007, only six running backs hit the 300-carry mark. A huge drop-off from previous years.

Those lost offensive opportunities shifted to the passing game. In 2007, there were eleven wide receivers with 90 or more receptions, up from seven the previous year.

Below is a graph showing the trend of highly-used wide receivers and running backs since 2000 (Data from Pro-Football-Reference).

These stats probably aren’t a surprise to most fantasy owners. Everyone knows that last year was a huge passing year in the NFL.

I was surprised, however, by the fact that wide receivers have never had such an advantage over running backs. Even in the early 2000s, wide receivers only held a one-player advantage.

Another interesting fact is that these two lines don’t cross frequently. The last time there was a shift from wide receivers to running backs in 2003, there were four solid years of running backs out-performing wide receivers.

Was last year a fluke or the start of a new trend? My guess is that this is a new trend that fantasy owners will need to keep in mind when drafting this year.

Most fantasy football articles are reports and analysis about current events. A month later, though, no one really cares how Steven Jackson’s groin was on October 3rd.

That’s why Doug Drinen’s archive of fantasy football ramblings is so interesting to read. He wrote a series of articles before the 2002 season, and a lot of them contain nuggets of fantasy information still useful today.

If you haven’t had a chance to read them, check out the main page first before heading over to the full list.

A couple highlights:

The best wide receiver of a rookie class is practically never the best career receiver.

The best running back of a rookie class is almost always the best career back.

If I have time I’ll try to do my own update on some of his articles, but I wanted to first share his archive with anyone not familiar with it. I know in one of the articles he studies the third-year wide receiver breakout theory, but I can’t remember which one.

Start browsing now. It’s a great way to kill time. To keep it interesting, some of the articles are entirely opinion like the Randy Moss and Jake Plummer ramblings.

I mentioned last week that I’m a fan of Pro Football Prospectus, and this year’s edition is definitely worthwhile.

One article that I find interesting is the study of how a wide receiver’s height and BMI can be an indicator of success.

The way they predict success is by determining whether or not a player falls into one of four sections on a chart of height versus BMI. The study pooled data from the past ten years and compared players by looking at average yards per game.

Here is a rough sketch of their complete graph with some representative players shown:

The theory is that if a player falls into one of the four boxes, they have a decent chance of being a top wide receiver. Conversely, if a player doesn’t have a body type that fits into one of the four boxes, then they have only a small chance of being an elite receiver.

If you’re wondering how big these relative differences in body type are, below I added myself for comparison. At 6′ 2″ and 170 lbs, I fall just a bit on the light side of a successful NFL wide receiver:

This article is by far the most extensive study I’ve seen on how well body type can predict success. I am a little hesitant at the moment to take the results as fact though.

The main reason is that I don’t think there is enough data to justify drawing four separate zones on this graph. The theory is probably overfitting the data. For example, the height difference between the top and bottom zones is only two inches.

Second, I’m not convinced there is a legitimate football-related reason why these narrow zones of body type would be successful and others wouldn’t. Especially that dead zone in the middle. Is there a reason why a player with that height/BMI combination is less likely to be successful?

The article suggests that the reason for these zones is that they identify which body types are able to get separation from cornerbacks and which are useful as large targets for a quarterback. They also propose that looking at the body types of defensive backs could help determine if these wide receiver body types create favorable mismatches.

Although I’m skeptical, I’m always on the lookout for hidden trends and new ways to predict successful players. I’m going to watch this one for the next few years to see if these body type trends continue.

If a new successful player emerges with a body type that is right in the middle of those four zones, I think this theory is busted. If not, and the trends continue, this could be a real way to predict success within a group of players that is usually just a crap shoot.

If anyone is interested in fantasy football auctions, FantasyAuctioneer has written an article about recent auction values of players. He notes that Randy Moss and Tom Brady have lower values in auctions than they do in drafts. Interesting read, especially if you’re doing an auction this year.