### Distribution

• Beta
• p(x) = $\frac{x^{\alpha-1} (1-x)^{\beta-1}}{B(\alpha, \beta)}$
• $B(\alpha, \beta)$

• Chi Square Distribution
• $Q \sim \chi^2(k) = \sum_{i=1}^{k} Z_i^2$.
• $Z$ is standard normal $k$ is degree of freedom.
• Mean = $k$. Variance = $2k$.