Knowledge Base – Betting Glossary -

Gecko Edge Betting Glossary

🎯 Core Concepts

Expected Value (EV): A measure of whether a bet is profitable long-term. A +EV bet means the odds are higher than the true probability.
Implied Probability: The chance of an event happening, based on bookmaker odds. Example: 2.00 odds = 50% implied probability.
xG (Expected Goals): A stat that measures the quality of chances created, showing how many goals a team should score on average.
Goal Averages: The average number of goals scored or conceded per game by a team, often used in Over/Under markets.

📈 Modelling & Analysis

Poisson Model: A statistical model to estimate likely scorelines and probabilities based on historical goal data.
Bayesian Models: Advanced models that update predictions as new data comes in (e.g. during a match).
Momentum Shifts: Tracking swings in game control (possession, shots, pressure) to anticipate turning points.

💰 Betting & Trading

Over/Under Goals: A market where you bet if a match will have more or fewer goals than a set number (e.g. Over 2.5).
BTTS (Both Teams To Score): A market where you bet on whether both teams will score at least one goal.
Asian Handicap (AH): A market that evens the playing field by giving one team a head start (e.g. +1 goal).
Staking Plan: A strategy for how much to stake on each bet (e.g. level stakes, % bankroll, progressive systems).
Liability: In exchange betting, the amount you risk when laying a bet.

📊 Trading Terms

In-Play Trading: Placing bets while the match is live, often to profit from odds swings.
Lay Bet: Betting against an outcome (e.g. laying a team to win).
Back Bet: Betting for an outcome (e.g. backing a team to win).
Cash Out: Locking in profit or reducing risk by closing a bet before the match ends.

⚖️ Safer Gambling

Betting & Trading Terminology

Arbitrage (Arb): Taking advantage of differing odds across bookmakers to guarantee profit.
Closing Line Value (CLV): How your bet’s odds compare to the final odds before kickoff. Beating the closing line usually means long-term profitability.
Overround / Vig (Juice): The bookmaker’s margin built into odds.
Value Bet: A bet where your assessed probability is higher than the bookmaker’s implied probability.
Dutching: Spreading stakes across multiple outcomes to lock in profit or balance risk.
Drip Feeding: Entering the market with staggered bets rather than one lump stake.
Hedging: Placing additional bets to secure profit or limit loss regardless of outcome.
Yield: Profit percentage relative to total stakes.

Mathematical & Modelling Concepts

Kelly Criterion: A staking formula that optimises bet size based on edge and bankroll.
Regression to the Mean: The tendency for extreme results to move closer to average over time.
Standard Deviation (SD): Measures variability (e.g., a high SD in goals means a team’s matches are unpredictable).
Sample Size: The number of matches/events used to calculate stats — small samples = less reliable.
Confidence Interval: A range that shows the uncertainty around a prediction.
Bayesian Updating: Adjusting probabilities dynamically as new data (like in-play stats) arrives.
Expected Points (xPts): Predicted league points based on xG and chance quality rather than actual results.
Win Probability Models: Using statistical frameworks (Poisson, Monte Carlo simulations) to estimate true odds.
Market Efficiency: How well bookmaker odds reflect true probabilities.

Football-Specific Statistics

xGA (Expected Goals Against): The quality of chances conceded.
NPxG: Non-penalty expected goals (removes penalties to give a clearer attacking picture).
PPDA (Passes Allowed Per Defensive Action): A measure of pressing intensity.
Deep Completions: Passes completed within 20m of goal (not including crosses).
Shot-Creating Actions (SCA): Passes, dribbles, or fouls that lead directly to shots.
Goal Conversion Rate: % of shots turned into goals.
Save Percentage: % of shots on target saved by a goalkeeper.
Possession Value Models (OBV, xT): Advanced models estimating how much each possession increases a team’s chance of scoring.
Form Index: Rolling average performance metric across recent matches.
Variance in Results vs. xG: Measuring how lucky/unlucky teams are compared to their expected performance.

Staking & Bankroll Management