PDF of Lecture Notes - School of Mathematical Sciences
PDF of Lecture Notes - School of Mathematical Sciences
PDF of Lecture Notes - School of Mathematical Sciences
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1. DISTRIBUTION THEORY<br />
3. Gamma (K, λ) distribution can be interpreted as the waiting time until the K th<br />
occurrence in a Poisson process.<br />
1.2.4 Beta density function<br />
Suppose Y 1 ∼ Gamma (α, λ), Y 2 ∼ Gamma (β, λ) independently, then,<br />
Remark:<br />
X = Y 1<br />
Y 1 + Y 2<br />
∼ B(α, β), 0 ≤ x ≤ 1.<br />
Figure 8: Beta Distribution<br />
1.2.5 Normal distribution<br />
X ∼ N(µ, σ 2 ); M X (t) = e tµ e t2 σ 2 /2 .<br />
1.2.6 Cauchy distribution<br />
Possible values: x ∈ R<br />
<strong>PDF</strong>: f(x) = 1 ( ) 1<br />
; (location parameter θ = 0)<br />
π 1 + x 2<br />
10