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Archive for September, 2008

Life at the 1

Posted by Chase Stuart on September 29, 2008

What's the difference between a touchdown and the ball at the one yard line? A touchdown is worth either 6, 6.4, 7 or potentially 8 points, depending on who you ask. Sticklers for details will tell you that a touchdown is no guarantee of a successful extra point, and is only worth six points. Most people will say that a TD is worth seven points, as teams that score touchdowns almost always come away with seven points. A touchdown is worth potentially 8 points, of course, because if you're down by 8 you only need a touchdown to have a chance to tie.

And David Romer would tell you that a touchdown is worth 6.4 points -- just like a field goal is worth 2.4 points -- because following the mandatory kickoff the opposing team gets the ball at around the 27 yard line. And having the ball at around the 27 is worth about 0.6 points.

Arguments about the worth of a touchdown aside, the ball at the one is almost always going to be less valuable than a touchdown. But we know it's not much less valuable. So, in fact, how much less valuable is it?

Ignoring the final minute of each half, teams had first down at the one yard line about 108 times in 2007. (I say about, because while my data is as close to complete and as accurate as any I know of, it's certainly possible and even likely that I'm missing some specific plays.) What happened on those 108 "drives"?

On first down, 20 of the 108 teams threw the ball. Of those, 12 went for completions, and all twelve were touchdowns. Eight passes went incomplete, along with zero sacks and zero interceptions. Obviously 88 plays were rushes (although some may have been designed pass plays that turned into QB runs), with 38 of them going for touchdowns. Eight teams lost two, three or four yards. Eleven teams lost one yard (with one fumble lost) and 31 gained zero yards (with one holding penalty, meaning the team started at the 11 despite gaining zero yards on the rush).

To conclude, of the 108 plays in first and goal at the one situations (excluding those with one minute left in either half), 50* of them were touchdowns, 38 gained zero yards, one resulted in a fumble lost, and 19 left the teams with the ball and further away from the goal line. On second down, of the 38 plays from the one, 15 times the team ran for a touchdown and six times they threw for a score. Of 19 plays run from farther out, four times the team threw for a score and zero times the team ran for a score. One interception was thrown. That leaves 31 plays for third down.

Five teams a team threw for a score; six times a team ran for a score. Two times a team threw an interception. Once a team threw for a score, had the play nullified by a penalty, and then scored on the ensuring third down attempt. So what happened on 4th down?

On the 17 remaining plays, 11 times the team kicked a field goal and all eleven were successful. Six times the team went for it, resulting in two touchdowns and four turnovers on downs.

To sum, 108 teams last year had the ball at the opponent's one yard line on 1st down, with more than one minute to go in the half. 89 times (82.4%) the team scored a touchdown and 11 times the team scored a field goal. Four times the team turned the ball over, and four more times the team went for it and failed on fourth down.

It's not too difficult to value the touchdowns and the field goals. What about the turning the ball over and the failed fourth down conversions? The fumble was recovered at the four. Two of the interceptions were recovered in the end zone and downed there; one was returned to the six yard line. Obviously four isn't a large enough sample size to feel confident about anything, but the average field position the opponent took over the ball following the turnover was the 12.5 yard line.

The turnover on downs data are probably more reliable. The defenses took over at the two, five, twelve and fourteen yard lines -- on average, the 8.25 yard line. For all eight turnovers, the opposition took over at roughly the ten yard line.

We could re-look at the 2007 data as follows: 82.4% of the time teams facing 1st and goal from the one eventually score a touchdown; 10.2% of the time those teams settle for a field goal, and 7.4% of the time the defense ends up with the ball before any scores, at around the ten yard line.

Using Professor Romer's logic, this means 82.4% of the time a team scores 6.4 points, 10.2% of the time a team scores 2.4 points, and 7.4% of the time a team scores about +0.35 points. Where'd I get that last number from? According to Romer, 1st and 10 from your own 10 yard line is worth about -0.35 points. So our offense that fails to score still puts its team in a position where it's more likely to score than next. If we weight our averages, that means 1st and 10 at the one yard line is worth between 5.5 and 5.6 points. Since a touchdown is worth 6.4 points, this means 1st and goal at the one is about 86-87% as good as a touchdown. It's worth noting that Professor Romer reached the same exact result. According to his graph, 1st and goal at the one is worth 5.55 points. I wasn't sure if he was right or not, but my query today makes me feel very confident that he was.

*I'll be discussing more plays from the one yard line tomorrow, but it's worth noting that only 50 of the 108 rushes on 1st down scored touchdowns. That rate of 46% is pretty low -- on other downs and in general 3rd or 4th and 1 situations, teams convert at around a 55% clip. I checked the 2006 data (unfortunately, the rest of the data is too cumbersome to go back to '05 or '06 at this time) and the conversion rate was only 49%. But in 2005, the conversion rate was an incredible 65%. The weighted three year average was 54%, which is in line with what you'd expect.

8 Comments | Posted in General

When should the Lions have given up on Joey Harrington?

Posted by Jason Lisk on September 19, 2008

In June, Chase Stuart wrote a series of posts about quarterbacks, including the worst quarterbacks of all-time. In that post, he had this to say about Joey Harrington:

There you have it — no QB has performed so far below the league average for so long as Joey Harrington. To be clear, Joey Harrington probably isn’t the worst quarterback of all time in an absolute sense. But in terms of being so far below average, but far enough above miserable to earn more playing time, Joey Harrington hurt his team more than any other QB in NFL history. If Harrington had been worse, he would have played less, and he wouldn’t have set back the teams he played on.

So that got me thinking. At what point should the Lions have given up on Joey Harrington? Let me define what I mean by "give up". It could mean releasing or cutting the player, but I don't necessarily mean waiting until that point. I more consider it the point at which the team should bring in a veteran quarterback, or another high draft pick, to legitimately compete as the starter and potentially beat out Harrington--and I don't count Mike McMahon as doing that. It's just hard to say all of that in a quick and easy way.

Chase opined that the reason that so many of the "bad" quarterbacks were recent high draft picks is because teams give them many opportunities to fail. I think that's right. And I'll go so far as to say that teams are far more likely to commit errors of holding on to a quarterback for too long, while rarely giving up on a quarterback to early--once they have seen him play any amount of time in a real NFL game. I can think of examples of quarterbacks who were drafted, never started for their original team, and found success elsewhere, but its relatively rare to find a quarterback who started but never had success with his original team, and moved elsewhere to have his first breakout.

But I think NFL teams who hold on to a bad quarterback for too long are compounding their problems, and committing a new and independent error. Drafting Joey Harrington may have been a mistake, but having him as the best quarterback on the roster, and starting him for four years, is a bigger one. All NFL teams make drafting mistakes or get unlucky, but the good teams move on quicker and do not compound their mistakes.

We can probably think of examples of young quarterbacks struggling, but was there a point at which Harrington's career path and numbers diverged from the quarterback successes? After all, he was the primary starter for four seasons--surely the decision could have been made before then.

13 Comments | Posted in General

Guest post: Best Draft Classes Revisited

Posted by Doug on September 17, 2008

Article by frequent pfr-blog commenter Richie Wohlers. Any transcription errors are the fault of Doug.

About 5 years ago I began a project where I wanted to try and evaluate NFL draft performances over the years. I wanted to come up with a simple method for evaluating all NFL players, regardless of position. I decided that the main goal of an NFL team when it drafts a player is to draft a player who is going to play in NFL games. So I figured I could just rate all players by the number of games they played. I decided to also award bonus points for players who made Pro Bowls or the HOF.

So I began to manually enter this information for all players. I could get some information from NFL.com and some from this website. But all the data was not available for all players. Needless to say, I never got too far in my task. I completed the 1999 draft for all players I could find, and then I pretty much put my project on the backburner. Then, pro-football-reference.com added all this wonderful draft data and games played stats for basically every player since the 1950's, I could finally finish my project. I was just about done with my research when Doug came up with his Approximate Value formula and did a research project that was similar, yet superior, to mine.

Even though my method is more of an estimate than the AV method, and even though we've read a couple of posts on a similar topic, I went ahead and finished my research. I pulled out a few pieces of information which are a little different than what Doug and Chase have already posted in the past few months.

15 Comments | Posted in History, NFL Draft

Reports of New England’s demise are greatly exaggerated

Posted by Doug on September 13, 2008

I'm hearing and reading a lot of crazy stuff this week.

So I just want to document my predictions that (a) the Patriots will win at least 11 games this year, (b) the Patriots will clinch the East before week 17, and (c) Matt Cassel will be a top-12 fantasy quarterback from here out.

That is all.

28 Comments | Posted in General

2008 stats

Posted by Doug on September 12, 2008

This is our first time doing weekly updates with the new format, so it has taken a bit of time to get the week one stats to the site. They should be up sometime today, hopefully by the time you read this.

In general, p-f-r will update every Monday and/or Tuesday as it always has.

Thanks for your patience.

3 Comments | Posted in General

Michael Turner and what to expect from a 200 yard rusher the week after

Posted by Jason Lisk on September 11, 2008

I don't think its an overstatement to say that Michael Turner had a fantastic debut as a starter for the Atlanta Falcons last week. Over on the footballguys message boards, a poster named Abstract posed this very concrete question:

I was just sitting here thinking about Michael Turner's outstanding performance last week and it got me to thinking. Does anyone know what history says about how a guy does following his 200 yard blow up? What does he normally do the next game?

Well, that's what we are here for. What do guys who have big rushing weeks do as an encore? The short answer is, they usually don't run for 200 yards the next game (only one player had back to back 200 yard games since 1995, can you name him?). If your memory is clouded by the most recent occurrences, you might be tempted to guess they don't do so well, based on Jamal Lewis and Adrian Peterson's follow up performances (twice) last year. Neither of those guys reached 70 rushing yards the following week.

As it turns out, it was those performances that were the exception. Certainly, the numbers regress the following week after a truly exceptional performance. But if you are wondering whether Michael Turner is likely to have a pretty good performance next week, based on history, the answer is yes.

Going back to 1995, there have been fifty occasions where a running back has rushed for at least 200 yards in a regular season game. Eight of those occurred in the final week of the regular season, so we will throw those out. For the remaining 42 cases, the running back played in the next game in all of them. Here's how they did:

As a group, they averaged 21.4 rush attempts, 94.8 rushing yards, 24.1 receiving yards, and 1.0 total touchdowns the following week. In a non-points per reception scoring format, they averaged a pretty healthy 18.0 fantasy points the next week.

Just over half of them (22) rushed for at least 100 yards the following week. Over half of them (23) had at least 125 total yards the following week. Twenty-nine (69%) of them scored at least one touchdown the week after. Only seven of them compiled fewer than 100 total yards while also failing to score a touchdown, including both Lewis and Peterson (after the San Diego game) last year.

Okay, but Turner did it on only 22 carries, which included a 66-yard touchdown. What if we only look at the guys who reached 200 carries on relatively low rushing attempt totals. Last year, Doug posted the list of 200 yard games with the fewest rushing attempts. Turner's effort would now rank on that list tied for fifteenth. Every back that gets to 200 rushing yards in a game is necessarily getting some yards in chunks, but perhaps backs that reach it with fewer attempts regress more the following week because it was more related to the luck of one or two long runs.

While I can't go back and tell you how Cliff Battles followed up his 200 yard rushing game for the Boston Redskins in 1933, I can look at the players since 1995. Besides Turner, thirteen players have rushed for 200 or more yards in a game on 25 or fewer rushing attempts. Here's how they followed up the next week:

21.9 rush attempts, 100.3 rush yards, 25.2 receiving yards, 1.1 touchdowns, 19.0 fantasy points

So, the low carry group actually did slightly better than the group as a whole. Only three of them failed to reach 100 total yards the following week--Adrian Peterson last year against Dallas, Willie Parker in 2006 against Cleveland, and Marshall Faulk in 2000 against Kansas City (Faulk had 99 total yards). Only three of them failed to score a touchdown the week after--Warrick Dunn in 2000 against Miami, Edgerrin James in 2004 against Detroit, and Tiki Barber in 2005 against San Fransisco. Tiki Barber's 10.3 fantasy points were the fewest among this group. Barry Sanders had the most, with an encore performance of 167 rushing yards and 3 touchdowns against the Bears in 1997.

If you came here for fantasy advice, waffling on whether you should start Michael Turner or Julius Jones this week, my advice, as controversial as it may be, is go ahead and start Turner.

8 Comments | Posted in General

Contest summary

Posted by Doug on September 8, 2008

These are not quite official (I need to check my spam queue for entries and maybe clean some things up), but this should be pretty close to what the official percentages end up being.

A number of these questions have taken interesting turns already, but that was inevitable.

We hope to update this thing every few weeks with what we might call "intelligently subjective" estimated standings and win probabilities. That said, here are (roughly) the percentage of contestants that took each side:

44.1 - Number of wins by the Texans
54.2 - Number of wins by the Panthers

27.1 - Number of wins by the Jaguars
72.9 - Number of wins by the Cowboys

20.3 - Number of wins by the Browns
79.7 - Number of wins by the Packers

35.6 - Number of wins by the Lions
64.4 - Number of wins by the Ravens

49.2 - Number of wins by the Cardinals
50.8 - Number of wins by the Redskins

64.4 - Number of wins by the Saints
35.6 - Number of wins by the Giants

71.2 - Number of wins by the Chargers
28.8 - Number of wins by the Raiders and Falcons combined

23.7 - Number of wins by the Rams and 49ers combined
76.3 - Number of wins by the team with the most wins

50.8 - Number of wins by the Bears
49.2 - Number of wins by the last place team in the AFC South

30.5 - Number of home wins by the Bills
69.5 - Number of road wins by the Colts

83.1 - Number of wins by AFC West teams
16.9 - Number of wins by NFC West teams

47.5 - Number of games started by QBs drafted in the 2008 draft
52.5 - Total number of TD passes thrown by the Jets.

27.1 - Number of receiving TDs by Randy Moss
72.9 - Number of combined receiving TDs by Sidney Rice, Vincent Jackson, Isaac Bruce, and Anthony Gonzalez

13.6 - Number of distinct players to have a 100-(or more)-yard rushing game
86.4 - Yardage of the longest passing TD thrown by a Falcon.

88.1 - Number of rushing yards by LaDainian Tomlinson
11.9 - Number of combined passing yards by all 49er players EXCEPT FOR the week one starting QB.

66.1 - Number of combined kick and punt return TDs by Devin Hester
33.9 - Number of combined kick and punt return TDs by Josh Cribbs

50.8 - Number of receiving TDs by Reggie Bush
49.2 - Number of rushing TDs by Vince Young

57.6 - Number of interceptions thrown by Kurt Warner
42.4 - Number of interceptions thrown by Chad Pennington

55.9 - Margin of the Chiefs biggest win.
44.1 - Number of Rushing TDs scored by (the Vikings') Adrian Peterson

16.9 - Maximum number of points scored in a game by the Ravens
83.1 - Number of Passing TDs thrown by the league's leader in passing TDs

81.4 - Number of rushing yards by Brian Westbrook and Steven Jackson combined
18.6 - Number of rushing yards by Jerious Norwood, Fred Taylor, and Maurice Morris combined

35.6 - Number of receptions by the player with the MOST receptions from this group: Jason Witten, Kellen Winslow, Antonio Gates
64.4 - Highest single-game receiving yardage by a player from this group: Owen Daniels, Tony Scheffler, Zach Miller

55.9 - Maximum number of passing TDs by a player from this group: Jeff Garcia, Tarvaris Jackson, Chad Pennington, Trent Edwards
44.1 - Minimum number of passing TDs by a player from this group: Tony Romo, Peyton Manning, Carson Palmer, Ben Roethlisberger

49.2 - Number of players in the NFL's top 10 in rushing yards who were born in the 1970s
50.8 - Number of players who throw 32 or more TD passes

44.1 - Number of games started by Brodie Croyle
55.9 - Number of games started by Kyle Orton

27.1 - Number of Kris Brown missed field goals
72.9 - Number of Edgerrin James rushing TDs

39.0 - Number of Larry Johnson rushing yards
61.0 - Number of Braylon Edwards receiving yards

55.9 - Number of total TDs scored by Marion Barber III
44.1 - Number of Mario Williams sacks

54.2 - Number of divisions whose 2008 champ is the same as the 2007 champ
45.8 - Number of divisions whose 2008 champ is NOT the same as the 2007 champ

18.6 - Number of postseason games decided by 7 or more points
81.4 - Number of rushing TDs by the player with the MOST rushing TDs from this group: Chris Johnson, Matt Forte, Kevin Smith, Ray Rice, Darren McFadden

28.8 - Number of playoff (non-Super Bowl) games won by the visiting team
71.2 - Maximum number of TDs thrown by Drew Brees in a single game

35.6 - AFC Championships by Patriots and Jaguars
64.4 - AFC Championships by all other teams combined

40.7 - NFC Championships by the NFC East
59.3 - NFC Championships by teams not in the East

67.8 - Number of points scored in the AFC Championship game
32.2 - Number of points scored in the NFC Championship game

30.5 - Number of playoff games won by NFC South teams
69.5 - Number of playoff games won by the Patriots

40.7 - Super Bowl Championships won by the Pats, Colts, and Chargers
59.3 - Super Bowl Championships won by all other teams

40.7 - Number of receptions by the player with the MOST receptions from this group: Ryan Grant, Darren McFadden, Ronnie Brown
59.3 - Total points scored in the Super Bowl

62.7 - Number of interceptions thrown in the Super Bowl
37.3 - Number of double-digit losses suffered by the Cowboys during the regular season.

6 Comments | Posted in General

Don’t forget to enter the p-f-r contest

Posted by Doug on September 3, 2008

Details here. Two point bonus for entering before kickoff of Thursday's game.

Comments Off | Posted in General

AV all-franchise teams redux: NFC

Posted by Doug on September 2, 2008

Just for fun, I decided to use my Approximate Value method to come up with a post-merger all-franchise team for each franchise.

Throughout the dog days, I had been posting these by division, and I had been limiting these lists to post-merger players. But after six divisions were done, I revamped the AV formula to include seasons in the 1950--1969 range. So I'm going to post all the teams in two posts. This one is the NFC edition. Here is the AFC.

Here are the rules:

1. The AV systems gives a player a score for each player season. To combine these into a career number, I take 100% of the player’s best season, plus 95% of his second-best season, plus 90% of his third-best season, and so on.

2. I’m only comfortable (for now) applying the AV methodology to seasons 1950 and later. Players who debuted before 1950, however, are included if their post-1950 seasons alone merit inclusion. In this case, they have a ‘+’ after their AV score to remind you that their career AV is (probably) higher than the number shown.

3. To avoid 4-3/3-4/5-2 issues, I gave each defense 12 players, including two DT/NTs, two DEs, two OLBs, and two ILB/MLBs. I have also now lumped all safeties together instead of distinguishing between free and strong safeties.

4. Because of the slippery and changing nature of defining what a fullback is, I simply decided to go with two RB/FBs, instead of an RB and an FB.

5. What to do with players whose position was "End" in the 50s. Are they tight ends? Wide receivers? To deal with this problem, I've lumped TEs, WRs, and Es of all years into one category, which I've called 'RC' (ReCeiver), and I'm allowing four of them per team. After all, if the defense is playing with 12, I should allow the offense the same luxury.

As with most things AV-related, this series of posts is mostly just for fun, but I’m also curious to hear feedback from long-time followers of the teams about things that look fishy.

Here they are:

7 Comments | Posted in Approximate Value, General