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Archive for May, 2010

PFR Blog Mobile Stylesheet

Posted by Sean on May 26, 2010

I just implemented a mobile stylesheet for the blog. Please let us know what you think of it.

2 Comments | Posted in Announcements

How many YPC will RB X average this year? Part II

Posted by Chase Stuart on May 26, 2010

Note: All data came from and their excellent play-by-play data and game logs.

What can you make of a player who has a high yards per carry average on a low number of carries? Take Ahmad Bradshaw, for instance. He has 253 career carries and a 5.2 average gain -- does that mean he's much better than your "average" back? Or do we not have enough evidence yet to know how good he is?

I looked at the over 60,000 carries by NFL running backs over the past five regular seasons. Over that time, the average carry went for 4.20 yards, with a standard deviation of 6.27 yards and a median of three yards. The mode is two yards. Note that "the average carry" is something very different than the carry from an average running back, as the best running backs accumulate a disproportionately large percentage of league carries. Thomas Jones, LaDainian Tomlinson, Steven Jackson, Jamal Lewis, Larry Johnson, Clinton Portis, Willie Parker, Edgerrin James, Frank Gore and Willis McGahee had over 20% of the carries by running backs since '05, despite those 10 backs representing fewer than 4% of all running backs with a carry over that span.

Comments Off on How many YPC will RB X average this year? Part II | Posted in Statgeekery

How many YPC will RB X average this year?

Posted by Chase Stuart on May 24, 2010

What is the most accurate way to project a running back's yards per carry average for next season? What does history say about how many yards per rush Chris Johnson, Steven Jackson and Michael Turner will average in 2010?

I ran a query using all RBs since 1988 who had at least 200 carries in Year N, at least 100 carries in Year N+1 and did not switch teams in between years (I didn't want to bias the sample by potentially eliminating running backs who struggled so much in Year N+1 that they failed to receive 200 carries). After doing so, I wrote and finished this blog post ... and then realized that my analysis was incorrect. Why? Because I hadn't realized that yards per carry averages have been rising over the past 20 seasons. The table below shows all carries and rushing yards by running backs in the NFL since the merger:

year   carries rshyd   ypc    5yearaverage
2009   12390   53114   4.29   4.19
2008   12473   52985   4.25   4.17
2007   12417   51695   4.16   4.16
2006   12694   53253   4.20   4.16
2005   12738   51826   4.07   4.13
2004   12747   53334   4.18   4.11
2003   12759   53351   4.18   4.05
2002   12105   50285   4.15   4.01
2001   11711   47300   4.04   3.98
2000   11688   46649   3.99   3.95
1999   11861   46144   3.89   3.95
1998   11967   47559   3.97   3.92
1997   12046   48231   4.00   3.91
1996   11966   46651   3.90   3.92
1995   11734   46585   3.97   3.93
1994   11213   42051   3.75   3.94
1993   11233   44064   3.92   3.97
1992   10774   43545   4.04   3.99
1991   10924   43255   3.96   3.96
1990   10975   44456   4.05   3.95
Read the rest of this entry »

24 Comments | Posted in Statgeekery

PFR iPhone Users: should we style the blog for the iPhone

Posted by Sean on May 21, 2010

If you read our blogs on your iPhone, you will know that the site on the iPhone looks just like it does on a full browser. WordPress has a plugin that can present the blog in a iphone specific format to iphone users. Do you (a user of the blog on your phone) prefer this format on the blogs you read on your phone?

This change would not affect non-mobile users in any way.

4 Comments | Posted in General

Approximate Time of Knockout, Part II

Posted by Chase Stuart on May 21, 2010

Last Friday, I looked at something called the Approximate Time of Knockout. There were some great suggestions in the comments about improving the system, but unfortunately time and/or a lack of available data made most of them impossible to implement by today. First, let's take a look at the 2009 results, using exactly the same formula from last week:

NYJ 2009 16 9 344.3 21.5
GNB 2009 16 11 332.5 20.8
NWE 2009 16 10 321.8 20.1
IND 2009 16 14 309.8 19.4
MIN 2009 16 12 307.9 19.2
NOR 2009 16 13 306.5 19.2
PHI 2009 16 11 302.3 18.9
SDG 2009 16 13 280.8 17.5
ARI 2009 16 10 273.8 17.1
BAL 2009 16 9 267.0 16.7
DAL 2009 16 11 265.3 16.6
SFO 2009 16 8 258.8 16.2
ATL 2009 16 9 238.0 14.9
CAR 2009 16 8 222.5 13.9
CIN 2009 16 10 222.5 13.9
DEN 2009 16 8 212.5 13.3
NYG 2009 16 8 200.5 12.5
HOU 2009 16 9 192.3 12.0

6 Comments | Posted in Statgeekery

Support, Sponsor a Page

Posted by Neil Paine on May 17, 2010

Sponsoring a page is fun, fast, and easy way to support what we're doing here at Pro-Football-Reference. With a sponsorship, you can:

  • Show your support for your favorite player or team.
  • Drum up traffic for your own site & draw in fans with a common interest.
  • Get some well-deserved recognition for your support of PFR.
  • Make your voice heard by the tens of thousands of people who visit Pro-Football-Reference every day.

Here's all you have to do to get involved:

  1. Create a membership account.
  2. Find the page(s) you'd like to support, and click "sponsor" (available pages).
  3. If the page you want is already sponsored, click "Alert Me!" to be informed when the current sponsorship expires.
  4. Follow the instructions to create your message and make your payment.
  5. Your message and links will be visible on the page after we approve them (usually in less than 24 hours).

And who knows, if you're clever enough, your message might end up on lists like these.

Comments Off on Support, Sponsor a Page | Posted in Announcements

Approximate Time of Knockout

Posted by Chase Stuart on May 14, 2010

In December 2008, Doug talked about a metric called "Time of KO," measuring the time of knockout in any football game. Dr. Saturday, our favorite college football blogger, has been keeping track of this metric for a few years now. Like the simple rating system, it's just another way to measure and rank dominance; it's not designed to be the mother of all rating systems, but it is designed to provide another look at how each particular game unfolded. What it lacks in precision it makes up for in simplicity -- when did a knockout occur?

The short theory is that we look at how much time was remaining in every game when the winning team first scored more points than the losing team ultimately scored by the end of the game. In this past Super Bowl, that would be the first score of the 4th quarter, when the Saints went up 24-17 (ultimately winning 31-17). In the Eagles season opener against the Panthers, Philadelphia won 38-10. DeSean Jackson's punt return touchdown in the 2nd quarter made it 17-7, which would have been the knockout score in that game.

Unfortunately, we don't have data on how much time remained in the game during each score in NFL history; what we do have is the number of scores in each game and quarter. So we have to do a bit of a fugde -- hence the name, Approximate Time of Knockout. If there were four scores in the 2nd quarter of a game, we'll stipulate that the scores came with 12, 9, 6 and 3 minutes remaining in the quarter. In the Broncos 27-6 week 2 win over Cleveland, there were three scores in the first quarter; Cleveland kicked a field goal, then Denver scored a touchdown, and then Cleveland kicked another field goal. Therefore, the Broncos are given an approximate time of knockout of 52 minutes, 30 seconds -- there were three scores in the first quarter, and we assume that they came with 11:15, 7:30 and 3:45 remaining. In the Texans victory over the Bengals this season, Cincinnati scored 17 points; the Texans scored a touchdown to go ahead 21-17 on the first of two scores in the third quarter; therefore, we assume the time of knockout in that game was with 25 minutes remaining.

13 Comments | Posted in Statgeekery, Totally Useless

BYU’s 1984 Championship

Posted by Chase Stuart on May 11, 2010

Boise State may finally be on the verge of a BCS Championship Game appearance. The Broncos have won 24 consecutive regular season games, and an undefeated season in 2010 will run that number to 36. It will also mean that Boise State will have won on the East Coast against Virginia Tech, held off Oregon State, and run through the rest of their schedule without a loss. Boise State finished the '09 season as the #3 team in the country and returns 21 of 22 starters in 2010 (cornerback Kyle Wilson was drafted in the first round of last month's draft by the Jets). Bringing back nearly the entire roster from an elite team ensures that the Broncos will have a top-five pre-season rank. That may be enough to vault them into the title game, as a 25-0 record in '09 and '10 will be difficult to ignore. These facts prompted Dr. Saturday to compare BSU to the 1984 BYU Cougars, the only mid-major football team to ever be crowned national champion by the Associate Press.

The '84 Cougars have been profiled by many journalists; Stewart Mandel's excellent recap of their season serves as a terrific background for the uninitiated. John Underwood's article from the week BYU was crowned #1 is a great way to teleport to the mid-'80s (including some quotes by Penn State's elderly coach, Joe Paterno). The Cougars went 13-0, but didn't play any of the top teams in college football that season. Winning the WAC, then and now, is not tied to a prestigious Bowl game, and as a result, BYU ended up playing a depleted, 6-5 Michigan team in the Holiday Bowl. So what's the best way to determine how good the Cougars actually were? Was Brigham Young deserving of the national championship? Were they the best team in college football? This post seeks to answer those questions.

5 Comments | Posted in College, Statgeekery

Checkdowns: 2010 Average ages

Posted by Chase Stuart on May 7, 2010

Which team was the "youngest" in the NFL last year? There's only one real way to measure team age, and that's to calculate the AV-weighted age of each contributor on the team. I did that for the New York Times' Fifth Down blog. So check it out if you want to see the average AV-weighted ages for every team in the NFL last season; I also broke teams down into offense and defense. The Texans come out with the youngest defense in the league; the Pats have the oldest offense, and it might be even older in 2010.

2 Comments | Posted in Checkdowns

Lost E-mails and Feedback

Posted by Neil Paine on May 6, 2010

One of the things we pride ourselves on at Sports-Reference is that we respond to every e-mail and comment that users send us. Doug and co. have done that for PFR since the site launched in December of 2000, and I do that now in my capacity as User Affairs Coordinator. Unfortunately, we just discovered that our technology has been letting us down for the past few months. When investigating a separate feedback problem at Baseball-Reference, Sean discovered another 150 or so messages stuck in our spam filter, many of which were related to Pro-Football-Reference. Those were just from the past month, so it appears we've been losing a lot of legitimate messages to our spam filter for at least five or six months. We believe we have fixed the problem going forward, but if there is something you sent us that we did not respond to, please accept our apologies and resubmit it here:

2 Comments | Posted in Announcements

The Fearsome Foursome

Posted by Jason Lisk on May 6, 2010

If you have been following along with the "What Coulda Been" Tournament, the 1967 Rams are one of the four teams remaining. I said that I was going to write a little something about each of the four teams. Well, I decided to look at the origins of the Fearsome Foursome in regard to that Rams team, but then realized that I should probably just turn it into its own post.

The nickname "The Fearsome Foursome" is one of the legendary names in NFL history. The mention automatically brings visions of the Rams' defensive line of the 1960's. It is a really cool nickname, but would you believe that it was a cliched and common phrase used by writers even before it was applied to the now immortalized unit?

I went back through the Google News Archives to trace the origins of the term, as well as its origins with the Rams. The first use of the phrase "Fearsome Foursome" that I could find was in 1937, but it had nothing to do with football. The term was originally used to describe the conservative bloc on the United States Supreme Court.

There was occasional use of the term "fearsome foursome" in the 1940's. The first time I found it applied specifically to football was not in regard to a group of players, but rather a group of teams. An AP article from November of 1949 described the top ranked college teams of Oklahoma, Notre Dame, Army and California as the fearsome foursome. The following year, the name was first applied in print to a unit, but it was not a defensive line. The 1950 University of Washington offensive backfield (remember, they ran with a full backfield then of a quarterback, two halfbacks and a fullback), which featured future 49ers star Hugh McElhenny, was dubbed the "fearsome foursome" in numerous articles from that season. The name was later applied to offensive backfield players for Baylor University, West Virginia, Syracuse and Texas. The first use of the term in the NFL was in regard to the New York Giant defensive line, featuring Rosey Grier, Jim Katcavage, Andy Robustelli, and Dick Modzelewski. All told in the 1950's, there were almost 100 different articles using the term, a fair amount having nothing to do with football. It was rarely a capitalized term as a formal title for a group, and typically was just used as a descriptive phrase. By the 1960's, the phrase "fearsome foursome" had been used to describe, among others, a rugby unit, a crew team, a curling squad, a local bowling team, and a bad quartet of singers.

Two other NFL units had the nickname applied to them: the Detroit Lions in 1962 (the only team to beat Green Bay that year) and the San Diego Chargers of the AFL in 1963. A player on the original NFL fearsome foursome and one on the Detroit Lions' version would eventually become linked in the now famous Rams unit. Before the 1963 season, the New York Giants traded a 31 year old Grier to the Rams for John LoVotere and a draft pick, with papers bemoaning the demise of the fearsome foursome. There, he joined Merlin Olsen, already a pro bowler at age 23, a young promising defensive end named David Jones (you may know him as Deacon), and a solid veteran in Lamar Lundy.

I cannot determine when exactly the nickname was first applied to the Rams' unit. It is possible that it just came over with Grier, but I do not see any documented evidence in newspapers of that. I do not find any references in 1963 and the only article referring to them as a fearsome foursome in 1964 was this one in the New York Times. By the 1965 preseason, I did find references to the unit, and in fact, found one in this article from Utah, talking about a singing group named the Fearsome Foursome, featuring local hero Olsen, along with Jones, Lundy, and offensive tackle Charlie Cowan. The references to the Fearsome Foursome do pick up in 1965 and 1966, and it's fair to say that by then, they were already being called the Fearsome Foursome or at least, a fearsome foursome. I found thirty references over those two seasons, most in the local paper.

However, it was the 1967 season when the Rams' Fearsome Foursome really became the immortalized Fearsome Foursome that is now remembered today. In the preseason in 1967, Roosevelt Grier suffered an injury and retired, and in response, the Rams traded for Roger Brown of the Detroit Lions. The defense, and the team, took off. The Rams had not made the playoffs since 1955, and had their first winning season in eight years the season before. In 1967, the team led the league in both points scored and points allowed, and posted an 11-1-2 record and defeating the Colts on the season's final game to win the division. In 1967, seventy-seven newspaper articles extolled the virtues of the Fearsome Foursome, the most of any year. The Rams had the misfortune, despite their record and regular season victory over the Packers, of having to go to Milwaukee for a playoff game played in frigid conditions, and they lost.

Over the next decade, the identity of the Fearsome Foursome continued to change, with Lundy retiring a year later, and a new generation joining Olsen in the early 1970's. Still, the name Fearsome Foursome is now associated exclusively with the Rams. Once upon a time, it was not, as every notable group may have been a fearsome foursome.

9 Comments | Posted in History