Appendix D: Glossary of NFL Analytics Terms

A

ATS (Against the Spread) Betting record relative to the point spread rather than straight wins/losses.

Adjusted Metrics Statistics normalized for factors like opponent strength, era, or situation.

ADP (Average Draft Position) Mean pick number where a player is selected in fantasy drafts.

Air Yards Distance the ball travels in the air on a pass attempt.

B

Breakout Age Age when a player first achieves significant production (usually 80th+ percentile).

Bust Rate Percentage of draft picks/acquisitions that fail to meet expectations.

Bye Week Scheduled week off during the NFL regular season.

C

Catch Rate Percentage of targets that result in receptions.

CLV (Closing Line Value) Difference between bet placement odds and closing odds.

Completion Percentage Passes completed divided by passes attempted.

CPOE (Completion Percentage Over Expected) Actual completion rate minus model-predicted completion rate.

Coefficient of Variation (CV) Standard deviation divided by mean; measures relative variability.

D

DFS (Daily Fantasy Sports) Fantasy contests where new lineups are selected each week.

Dominator Rating Player's share of team's receiving/rushing yards and touchdowns combined.

DVOA (Defense-adjusted Value Over Average) Football Outsiders metric measuring efficiency vs. league average.

E

Elo Rating Chess-derived rating system adapted for football predictions.

EPA (Expected Points Added) Points contributed beyond expectation based on situation.

Expected Points (EP) Average points scored from a given field position/down/distance.

Expected Value (EV) Probability-weighted average of all possible outcomes.

F

FLEX Fantasy roster position that can be filled by RB, WR, or TE.

Fumble Rate Fumbles per carry or touch.

G

Game Script How the flow of a game (score, time) affects play-calling.

GPP (Guaranteed Prize Pool) DFS tournament with fixed prize pool regardless of entries.

H

HFA (Home Field Advantage) Statistical advantage enjoyed by home team.

Half-PPR Fantasy scoring format with 0.5 points per reception.

I

Implied Probability Probability derived from betting odds.

INT Rate Interceptions per pass attempt.

K

Kelly Criterion Formula for optimal bet sizing based on edge and odds.

L

Leverage In DFS: projection divided by ownership percentage.

Line (Betting) The spread, total, or moneyline set by oddsmakers.

M

MAE (Mean Absolute Error) Average absolute difference between predictions and outcomes.

Market Efficiency Degree to which prices/lines reflect all available information.

Moneyline Betting on straight winner without point spread.

N

Next Gen Stats NFL's player tracking data from on-field sensors.

Normalization Adjusting values to a common scale for comparison.

O

Over/Under Bet on combined score being above or below a set total.

Ownership (DFS) Percentage of lineups including a specific player.

P

Play Action Pass plays that begin with a run fake.

Power Rating Team strength metric often expressed in points vs. average.

PPR (Point Per Reception) Fantasy scoring format with 1 point per reception.

Pythagorean Win Expectation Expected wins based on points scored/allowed ratio.

Q

QBR ESPN's proprietary quarterback rating.

Quartile Division of data into four equal parts (Q1, Q2, Q3, Q4).

R

RAS (Relative Athletic Score) Composite combine score on 0-10 scale.

Regression to the Mean Tendency for extreme values to move toward average over time.

RMSE (Root Mean Square Error) Square root of average squared prediction error.

ROI (Return on Investment) Profit divided by initial investment, expressed as percentage.

Replacement Level Performance of the best freely available alternative player.

S

Separation Distance between receiver and nearest defender.

SOS (Strength of Schedule) Aggregate difficulty of a team's opponents.

Speed Score (Weight × 200) / (40-time)^4 - measures size-adjusted speed.

Success Rate Percentage of plays gaining expected yards for the situation.

T

Target Share Percentage of team's pass targets to a specific player.

TD Rate Touchdowns per attempt or opportunity.

TNF (Thursday Night Football) Short-rest game with schedule implications.

True Shooting Scoring efficiency accounting for 2s, 3s, and free throws (basketball term sometimes adapted).

V

Variance Statistical measure of spread in a distribution.

Vig (Vigorish) Commission charged by sportsbooks on bets.

VORP (Value Over Replacement Player) Points provided above replacement-level production.

W

Win Probability (WP) Model-estimated probability of winning at any game state.

WOPR (Weighted Opportunity Rating) Weighted combination of target share and air yards share.

Y

YAC (Yards After Catch) Receiving yards gained after the catch is made.

YPA (Yards Per Attempt) Passing yards divided by pass attempts.

YPC (Yards Per Carry) Rushing yards divided by rushing attempts.

YPRR (Yards Per Route Run) Receiving yards divided by pass routes run.

Statistical Symbols

This glossary covers terminology used throughout the textbook. Terms may have slightly different definitions in different contexts.