Probability Cheat Sheet

Core probability rules, conditioning, Bayes and independence for quant interviews.

Rules

P (A^{c}) = 1 - P (A)

P (A \cup B) = P (A) + P (B) - P (A \cap B)

P (A ∣ B) = \frac{P ( A \cap B )}{P ( B )}

P (A) = i \sum P (A ∣ B_{i}) P (B_{i})

P (B ∣ A) = \frac{P ( A ∣ B ) P ( B )}{P ( A )}

P (A \cap B) = P (A) P (B)

1 - (1 - p)^{n}