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這是台大推甄的考古題,小弟我碰到幾題想不到怎麼解,請各位大大幫忙 1. Suppose that X_1, X_2, ..., X_n is random sample from Gamma(v,θ), where v>0 is some known constant and θ>0 is an unknown parameter (a) Construct a uniformly most powerful test, with significance level α, for testing the hypothesis H_o:θ屬於{0.5,1,1.6,1.7,2} against H_1:θ屬於{2.5,3,6,8,10} 通常我們在做UMP test,虛無假設都是=、≦、≧這三類,這題是離散型的 我就不太知道怎麼下筆了QQ (b) Suppose that v=0.2 and there is a sample of size 180 with sample mean 0.3 . Under significance levelα=0.05, does the test in (a) reject H_0 or not? 2. Let X_1, X_2, ...,X_n be a random sample with E(h(X_1,X_2))=θ, where h(x,y) is a symmetric function. Moreover, let X_(1),...,X_(n) denote the order statistics of X_1, X_2, ...,X_n. Derive the conditional expection E(h(X_1,X_2)|X_(1),...X_(n)) 這題只知道題目要求條件期望值,順序統計量是充分統計量, 不過不知道該怎麼辦...... b 3. Let I(f)=∫f(x)dx and X_1,...,X_n be a random sample from a density a function g(x) on [a,b]. Find an unbiased estimator of I(f) & compute it's variance 4. Let X_1, ...,X_n be a random sample from a one parameter exponential family f(x|θ)=exp(θh(x)-H(θ)g(x)), where H'(θ)=h(θ) and h'(θ)>0 (a) Show that E(h(X)|θ)=h(θ) and Var(h(X)|θ)=h'(θ) (b) Find the uniformly most powerful level α test of H_0:θ≦θ_0 vs. H_1:θ>θ_0 先說這題的函數f(x|θ)是不是有打錯呢?? 指數地方應該是H(θ)+g(x) 才會是指數族吧?! 然後這題感覺照定義直接積分會積不太出來,請問有甚麼比較好的做法呢??? 感謝各位大大的指教以及幫忙 :) -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 180.177.113.19