Reading market odds

A market price is a trading number. It is not a forecast from the league, and it is not a suggestion to risk money. This preview does not show odds. The decimals below are a worked example, not a price from the file.

Decimal odds

Decimal odds include the stake. A price of 1.72 means a 1.00 stake would return 1.72 if that side won the series, stake included. You read it as a multiplier. You do not read it as a prediction.

Implied probability

Divide 1 by the decimal price. That percentage is the implied probability. Two prices in one match are not meant to add to 100%, because the margin is still in them.

Worked example, not a price from this preview: 1.72 and 2.15. Raw implied probability is about 58.1% and 46.5%.

The vig

Add the raw implied probabilities. The amount over 100% is the overround, also called the vig or juice. Divide each raw figure by that sum and the two fair probabilities add to 100%. The fair split is a cleaner reading of the same price. It is still only a reading of the price.

American prices, briefly

A minus number is the favorite. −150 means a 150 stake would win 100. A plus number is the underdog. +130 means a 100 stake would win 130. Convert a minus price by dividing the absolute price by the absolute price plus 100. Convert a plus price by dividing 100 by the price plus 100.

What the price is not

• It is not a model probability. That column is off on this site.
• It is not an edge. Comparing a model to a price is also off.
• It is not a closing line. CLV compares a logged price with the price at the close, and it grades the log. It does not tell you to bet.
• It is not stable on a short sample. A handful of series can make a team look certain.

This preview does not show odds or model probabilities. It does not accept wagers, and nothing is for sale.