A Spam Filter

Naive Bayes

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Bayes: posterior ∝ prior × likelihood of the evidence.
• Naive Bayes multiplies word likelihoods as if independent.
• In odds form, each clue multiplies the odds by its likelihood ratio.

Steps

1. Evidence from words
2. Toggle the words
3. One word, by hand
4. Looks like ham
5. Why “naive”?
6. Odds multiply