Guide To Football Analytics

Fantasy football has changed in many ways since its inception, but one of the key differences between fantasy players today, and those who played the game 20 years ago, is the adoption of advanced metrics. There are tons of football analytics used by your opponents, and it is important to understand what these terms mean if you want to not only be able to avoid falling behind, but parse through current fantasy sports content. 

To that end, I have put together a glossary of terms you should know. Not all of the terms you will see below will help you to win your league, but they should all be extremely helpful to further fantasy football discourse. In part two, I’ll spend some more time breaking down the metrics that can help you win.

Adjusted Line Yards: Football Outsiders metric that gives the number of yards per carry belonging to the offensive line.

Adjusted Net Yards Per Pass Attempt (ANY/A): Metric accounting for the total yards per pass attempt of a quarterback, including sack yardage, and awarding bonuses for touchdowns with penalties for interceptions. The formula is ANY/A = (pass yards + 20*(pass TD) – 45*(interceptions thrown) – sack yards) / (passing attempts + sacks).

Adjusted Sack Rate: Football Outsiders metric which gives sacks plus intentional grounding penalties per pass attempt, but adjusted for down, distance, and opponent.

Adjusted Yards Per Pass Attempt (AYA): Yards per pass attempt with adjustments made for touchdowns and interceptions. The formula is AYA = (pass yards + 20*(pass TD) – 45*(interceptions thrown))/(passing attempts).

Air Yards: Yards traveled in the air on pass attempts. Accounted for on both completions and incompletions. 

Adjusted Passing Air Conversion Ratio (aPACR): Pass efficiency metric developed by Josh Hermsmeyer. It is adjusted for depth of target, and gives multipliers to touchdowns and interceptions. The formula is aPACR = (pass yards + 20*(pass TD) – 45(interceptions thrown))/(air yards).

Average Depth of Target (aDOT): Average number of air yards on each pass attempt. Can refer to passes thrown by a quarterback, or targets received by a skill player. The formula is (air yards)/(pass attempts).

Completion Percentage Over Expectation (CPOE): (Completion percentage) – (expected completion percentage) for passers.

Defense-adjusted Value Over Average (DVOA): Football Outsiders metric that is adjusted for strength of schedule. Can measure the quality of a passing or rushing offense or defense, as well as the total units. Also sometimes broken down to individual receiver levels. 

Elusive Rating: Pro Football Focus metric that measures how difficult it is to tackle a runner with the football, independent of the blocking in front of him. The formula is Elusive Rating = (Missed Tackles Forced) / (Designed Run Attempts + Receptions) * (Yards After Contact Per Attempt * 100).

Expected Completion Percentage: NFL Next Gen stat that determines what a passers completion percentage is expected to be based on numerous on-field factors. The formula is not publicly sourced. 

Expected Points (EP): Represents the expected number of points to be scored by a team given the down, distance, field position, and time remaining. 

Expected Points Added (EPA): The difference in expected points from play to play. If the offensive team was at 2.1 expected points on first down, and 2.4 expected points on second down, we would say that the first down play was worth 0.3 EPA. 

In/Out Splits: Segments of data based on a particular piece of information. For example, splitting a quarterback’s fantasy production based on being at home or on the road. 

Market Share: Economic term to describe the portion of a market controlled by a particular company or product. In fantasy, this term can be used to describe the percentage of a particular statistic that is owned by a single player. For example, a receiver’s market share of targets would give us the percentage of team targets that player is responsible for. 

Pace: Football Outsiders statistic that explains team play rate in more sophisticated terms than plays per game. The base metric is seconds per play, and it can be split in numerous ways, with the most commonly used being situation-neutral pace. This definition discards plays when the score differential is greater than 10 points in the first half, plays when the score differential is greater than 8 points in the 3rd quarter, plays in the 4th quarter or overtime, and plays in the last five minutes of the first half.

Passing Air Conversion Ratio (PACR): Pass efficiency metric developed by Josh Hermsmeyer. It measures the rate at which air yards are converted to passing yards. The formula is PACR = (passing yards)/(air yards).

Personnel Groupings: Describes the positions of the players on the field at any given time for the offensive team. This is a two-digit number, with the first number representing the number of running backs on the field, and the second number representing the number of tight ends. The number of wide receivers can be represented by 5 – (total of the digits). For example, 12 personnel is one running back, two tight ends, and two wide receivers.

QBR: ESPN proprietary metric to explain the value of quarterback play. It is a number between zero and 100, and is adjusted to account for the strength of opposing defenses. QBR includes quarterback value as both a passer and a runner. 

Receiver Air Conversion Ratio (RACR): Receiver efficiency metric developed by Josh Hermsmeyer. It measures the rate at which targeted air yards are converted to receiving yards. The formula is RACR = (receiving yards)/(air yards).

Success Rate (SR): The percentage of plays that result in positive EPA. Could be broken down to individually assess passing, rushing, or receiving of either a team or specific player.

Weighted Opportunity Rating (WOPR): Overall receiving volume metric created by Josh Hermsmeyer, meant to include both market share of targets and market share of air yards. The formula is WOPR = 1.5*(Market Share of Targets) + 0.7*(Market Share of Air Yards).

Yards After Catch (YAC): Yards accumulated by a receiver after the catch.

Yards Per Route Run (YPRR): Pro Football Focus metric that breaks down receiving yards to the individual route level. The formula is YPRR = (Receiving Yards)/(Routes Run).

Yards Per Target (YPT): Metric that breaks down receiving yards to the individual target level. The formula is YPT = (Receiving Yards)/(Receiving Targets).