Market mechanics
Vig, hold, line movement, limits and the operational reasons a sportsbook prices the way it does.
How Sportsbooks Set Limits (and Why Winners Get Restricted)
Why do sportsbooks limit winners? Limits are a risk tool, not a punishment. How books set them by market, and what actually triggers a restricted account.
Why Betting Lines Move (and What a Move Is Telling You)
Betting lines move because the price has to change, not because the game changed. Here is what moves a line, what each type of move signals, and what to ignore.
What Is the Vig? The Price of Every Bet, Explained
The vig is the fee built into every sportsbook price. How to calculate hold from any two prices, why parlays and futures cost more, and what you really pay.
Other topics
Odds & probability
Reading American, decimal and fractional prices, converting between them, and turning any of them into an implied probability.
Bet types
Spreads, totals, moneylines, parlays, teasers, props and futures — what each one costs you in expectation.
Bankroll & staking
Flat staking, percentage staking, Kelly, and the maths of variance, drawdown and risk of ruin.
Advanced concepts
Closing line value, steam, middling, arbitrage and the ideas that separate a priced bet from a hunch.