Quick Recap — Probability Rules & Binomial

  • Conditional: P(AB)=P(AB)P(B)P(A|B)=\dfrac{P(A\cap B)}{P(B)}; independent P(AB)=P(A)\Rightarrow P(A|B)=P(A).
  • Bayes: P(AB)=P(BA)P(A)P(B)P(A|B)=\dfrac{P(B|A)P(A)}{P(B)}.
  • Binomial: P(X=r)=nCrprqnrP(X=r)={}^nC_r\,p^rq^{n-r}, with mean npnp and variance npqnpq.
  • Odds in favour of AA =P(A)P(A)=\dfrac{P(A)}{P(A')}.