CORTENNotes on
football data
Notes and tools for reading odds, probability and football data more carefully.
How to analyse a football match
Six checks for fixture, sample and odds data before kick-off.
Read the article ↗
How Spor Toto works
Understand 15-match picks, system columns and official results.
Read the article ↗How to analyse a fixture list
Rest intervals, home and away sequences, and testing patterns.
Read the guide ↗Why beating football odds is hard
A pre-registered fixture hypothesis tested on 15 leagues and 30,954 matches did not replicate.
Read the article ↗Odds and statistics glossary
Short definitions of 20 terms including odds, margin, HT/FT, BTTS, sample size and the Wilson interval.
Open the glossary ↗How to calculate the bookmaker margin
Raw and margin-free probability; basic normalisation compared with the power method.
Read the article ↗Double Chance explained
Deriving 1X, 12 and X2 probabilities from 1X2 prices.
Read the article ↗BTTS explained
Both-teams-to-score probability, its margin and a simple expected-goals calculation.
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Why repeating odds mislead
How multiple testing and small samples make chance look like a pattern.
Read the article ↗HT/FT explained
The nine outcomes of half-time/full-time odds, their probability and margin, with a synthetic example.
Read the article ↗Over 2.5 explained
From total-goals odds to probability, expected goals and reading past over percentages properly.
Read the article ↗How to analyse football odds
A starting guide to reading price, implied probability and historical samples together.
Read the guide ↗Opening vs closing odds
When the two prices are recorded and how the difference between them is calculated.
Read the guide ↗Why sample size matters
The same percentage carries different uncertainty in 5 and 500 records. See the Wilson interval with an example.
Read the guide ↗Free calculators
Poisson score, odds ↔ probability, margin, odds movement and sample interval — all in your browser.
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