【正文】
y在區(qū)間 [0,1]上均勻分布 ? 利用 [0,1]區(qū)間上均勻分布隨機數(shù)產(chǎn)生器抽取 Monte Carlo模擬 第三章 從概率分布函數(shù)的抽樣 (Sampling from Probability Distribution Functions) 直接抽樣法(反函數(shù)法) ( Sampling via Inversion of the cdf) 1. 基本原理 2. 連續(xù)型的隨機變量的抽樣 3. 離散型的隨機變量的抽樣 4. 幾個典型的例子 2. 連續(xù)型的隨機變量的抽樣 方法: 1. 產(chǎn)生在 [0,1]區(qū)間上均勻分布的隨機數(shù) ? = P?(0,1) ; )(1 ??? Fx注:需要知道累積分布函數(shù)的解析表達(dá)式,且累積分布函數(shù)的反函數(shù)存在 P?(0,1): [0,1]區(qū)間上均勻分布的隨機數(shù) 2. 令 F(x) = ?, 解方程得 x: 2. 連續(xù)型的隨機變量的抽樣 Since F1 (ξ)=x, or ξ = F(x) Proof the Inverse Method The Mapping from x to ? is onetoone. The probability for ? between value ? and d? is 1?d?, which is the same as the probability for x between value x and dx. Thus dxxfdxxFxdFd )()()( ????? Monte Carlo模擬 第三章 從概率分布函數(shù)的抽樣 (Sampling from Probability Distribution Functions) 直接抽樣法(反函數(shù)法)