5 Advanced NFL Stats That Fans Should Know

Advanced statistics have become a hot topic in recent years with the popularity of sabermetrics in baseball and the emerging "Moneyball" theory.

The idea that player evaluation can only be done by scouts is a thing of the past. Mathematicians and scientists have become valuable tools in the world of baseball and basketball as individual events like at-bats and shot attempts can be easily quantified.

The world of football has been a bit slower to adapt. Perhaps because there are so many variables within in play. Perhaps because football is a team sport and the idea of assigning values to players seems a bit too subjective. Or perhaps it's pure stubbornness.

What ever the reason may be, the world of football statistics has slowly been evolving and there are a few advancements that have come about in recent years.

In the past 15 years, there has been a technological revolution with HDTV, the strategic placement of cameras around football fields, and improved instant replay. The clash of these elements has allowed for the breakthrough of video analysis.

Video analysis gives people the opportunity to break down each individual play to collect data for interpretation.

Let's take a look at five statistics that currently exist that fans need to know about.

Total Quarterback Rating

TotalQBR or "Total Quarterback Rating" was designed in 2011 by ESPN.

The idea behind TotalQBR was the belief that the current quarterback rating that everyone uses is outdated and flawed.

The old quarterback rating only considered passing statistics and did not account for rushing statistics or situational football. By improving the old quarterback rating, ESPN sought out a way to accurately rank quarterbacks and their performances.

The Total Quarterback Rating has many different parts including: win probability, expected points, division of credit, and a clutch index. These values are put together in a long process of video analysis where each play is broken down into each of those factors and given an outcome. Although, unfortunately, the official formula to determine TotalQBR has not been released publicly.

Here is a complete guide to Total QBR put together by ESPN Stats and Information.

The top five quarterbacks last year according to TotalQBR were:

1. Aaron Rodgers - 85.2
2. Drew Brees - 84.0
3. Tom Brady - 74.2
4. Tony Romo - 70.1
5. Matt Ryan - 67.5

The statistic has served as an improvement over the traditional quarterback rating, and TotalQBR will undoubtedly become more widely used in 2012 and in the future.

Defense-Adjusted Value over Average (DVOA)

Defense-Adjusted Value over Average—or more commonly referred to as "DVOA"—is a statistic that was developed by the minds at Football Outsiders.

The statistic is created through video analysis. Every play throughout the NFL season is broken down and values are appropriately assigned.

Values are assigned to each player in each play relative to what the average NFL player would achieve in that given play. Then each value is adjusted for the strength of the opponent. It is a great statistic to normalize performance and evaluate individual player performance.

Here is a full break down on DVOA, the methodology and origin.

The top five teams in DVOA last year were:

1. Green Bay Packers - 28.3%
2. Pittsburgh Steelers - 23.7%
3. New Orleans Saints - 23.3%
4. New England Patriots - 22.5%
5. Houston Texans - 19.4%

Win Probability Added (WPA)

Win Probability Added (WPA) is a statistic that was put together by a site called Advanced NFL Stats. The Statistic is very similar to the WPA statistic that is prevalent in the NBA or Wins Above Replacement (WAR) in baseball.

The basis of Win Probability Added is that each play throughout the game is a chance for a team to score. Each play has an effect on the outcome of the game.

As stated on their website:

"

WPA starts with a Win Probability (WP) model of the game of football. Every situation in a game gives each opponent a particular chance of winning, and a WP model estimates those chances. The model created here at Advanced NFL Stats uses score, time, down, distance, and field position to estimate how likely each team will go on to win the game. For example, at the start of the second quarter, a team down by seven points with a 2nd-and-5 from their own 25 will win about 36 percent of the time—in other words a 0.36 WP.

"

Not surprisingly, the top WPA rankings all belong to quarterbacks due to the effect that they have on each game.

The top five quarterbacks last year were:

1. Tom Brady - 7.56
2. Drew Brees - 6.91
3. Aaron Rodgers - 5.85
4. Eli Manning - 4.72
5. Matt Stafford - 4.40

Elusive Rating

The "Elusive Rating" is a fun statistic that was developed by Pro Football Focus.

The idea behind the elusive rating was to look at how hard a runner was to bring down. It's not as simple as simply looking at yards after contact. A player's ability to shake a defender or out run a defender to the corner is not taken into consideration when looking at yards after contact, so this is a good upgrade over the traditional statistics that fans use.

According to Pro Football Focus, the formula for the "Elusive Rating" is [(Missed Tackles Forced)/(Carries+Receptions)]*[(Yards after contact per attempt)*(100)].

The top five running backs last year in the elusiveness rating were:

1. Michael Turner - 64.3
2. LeGarrette Blount - 59.8
3. Ben Tate - 55.1
4. Matt Forte - 52.6
5. Adrian Peterson - 48.4

Pass Rushing Productivity

Another statistic developed by Pro Football Focus, "pass rushing productivity" attempts to quantify how often a player creates pressure on passing plays with an emphasis on sacks.

The statistic is more of a "rating" because it looks at how each player performs on a per-snap basis rather than their numbers as a whole.

The formula according to Pro Football Focus is [(Sacks)+(Hits)*(0.75)+(Hurries)*(0.75)]/(Pass Rush Attempts)

The top five players in 2011 in pass rushing productivity were:

1. Aldon Smith - 15.4
2. James Harrison - 13.6
3. Cameron Wake - 12.9
4. DeMarcus Ware - 12.9
5. Brian Orakpo - 12.2

Pass rushing productivity is a great statistic to evaluate players who may not play every down. There are many players throughout the league who play on a rotational basis and this statistic attempts to remove the bias of simply looking at sack totals to evaluate a pass rusher.