A question about deriving distribution - Statistics版 - 未名存档

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Statistics版 - A question about deriving distribution

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话题: deriving话题: balls话题: question话题: var

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t**i 发帖数: 688	1 Suppose we have an urn with n balls. Randomly take m (m replacement for K repeats. Denote X = frequency of a ball being samples. Then E(X) = m/n. What is the variance of X?
e******e 发帖数: 3472	2 let Z_i=1/0 if the ball is/not sampled in the i-th repeat Var[sum(Z_i:i=1,2,...,K))/K]=Var(Z_1)/K=m/n*(1-m/n)/K

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● 一个概念题	● 请教如何用proc glimmix 分析 repeated measures with binary outcome.
● 请教一个概率问题	● Random and repeated in mixed model
● 这样还能算Randomized sample吗	● 请高手帮我看看：glimmix model 有更好的建议吗？
● random sampling in R	● mixed model DF 问题

相关话题的讨论汇总
话题: deriving话题: balls话题: question话题: var

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