Reference

Appendix and Quick Reference

Use this section when you need the condensed version: terminology, formulas, compact examples, red flags, and study directions.

GlossaryFormulasWorked examples

AppendixGlossary

Term Meaning
Break-even rateThe win percentage needed to make zero expected profit at a given price.
CLVClosing line value. A comparison between your number and the market’s closing number.
Decimal oddsTotal return multiplier including stake.
EdgeThe amount by which your estimated true probability beats the market price.
Expected valueThe average amount you expect to win or lose per bet over many repetitions.
HookThe half-point attached to a line, such as 3.5 or 47.5.
Implied probabilityThe probability implied by the sportsbook price.
Juice / VigThe sportsbook’s built-in margin.
Kelly criterionA formula for staking based on estimated edge and payout.
Market makerA book or trading desk that originates respected prices.
MoneylineA bet on who wins the event outright.
ParlayA multi-leg ticket where every leg typically must win.
PushA tied result against the posted number, usually returning stake.
SpreadA handicap applied to one side to balance the betting market.
TotalA bet on whether combined scoring lands over or under the posted number.
UnitA standardized bet size used for bankroll management.
VarianceThe normal swing between short-term results and long-run expectation.
VoidA canceled bet that usually returns stake.

AppendixFormula Sheet

Odds to Implied Probability
$$P_{\text{neg}} = \frac{|A|}{|A| + 100}$$
$$P_{\text{pos}} = \frac{100}{A + 100}$$
$$P_{\text{decimal}} = \frac{1}{D}$$
$$P_{\text{frac}} = \frac{B}{A + B}$$
Expected Value
$$\text{EV} = (p_{\text{win}} \times \text{profit}) - (p_{\text{loss}} \times \text{stake})$$
Remove Vig (Two-Way Market)
$$P_{\text{no-vig}} = \frac{P_{\text{implied}}}{\sum P_{\text{all sides}}}$$
Kelly Criterion
$$f^* = \frac{bp - q}{b}$$
where $b = \text{decimal odds} - 1$, $p = \text{estimated win probability}$, $q = 1 - p$

AppendixWorked Examples

Example 1: Convert -110 to Probability

$\frac{110}{110 + 100} = 52.38\%$. That means the book is asking you to accept a price that requires a 52.38% win rate to break even.

Example 2: Remove Vig from -110 / -110

Each side implies 52.38%. Total implied = 104.76%. Normalize each side: $\frac{52.38}{104.76} = 50\%$. The no-vig market says each side is roughly 50/50.

Example 3: Positive EV at +150

If you estimate a 45% win chance, the fair decimal price is about 2.22, or fair American around +122. At +150, the book is offering a better price than your fair estimate, so EV is positive.

Example 4: Why a Good Bet Can Lose

If your edge says a bet wins 55% of the time, it still loses 45% of the time. Over ten bets, several losses in a row are perfectly possible. That is variance, not proof the edge is fake.

AppendixCommon Mistakes

  • Confusing “most likely winner” with “best bet at the current price.”
  • Ignoring vig and assuming two sides of a market must add to 100%.
  • Tracking wins and losses but not prices, units, or closing line value.
  • Betting too many markets without understanding their rules or margins.
  • Using parlays as a shortcut to profitability instead of a high-variance product.
  • Increasing stake size because of boredom, tilt, or recent results.
  • Letting live betting become an emotional chase environment.
  • Using betting money that belongs to ordinary life obligations.

AppendixResources

What to Study Next

Probability, statistics, market microstructure, and sport-specific scoring distributions are the most valuable subjects once the basics here feel comfortable.

What to Build Next

A personal tracking sheet, a no-vig price calculator, and a line-shopping routine are better first tools than a giant predictive model.

What to Check Before Betting

Your local rules, the book’s house rules, your bankroll limits, and whether the activity is still staying inside the boundaries you intended.