Let three random samples of sizes n1 20, n2 10, and n3 8 be taken from a population with mean and variance 2 Let S2 1, S2 2, and S2 3 be the sample variances Show that S2 (20S2 1 10S2 2 8S2 3)38 is an unbiased estimator of 2 ...

Let three random samples of sizes n1 = 20, n2 = 10, and n3 = 8 be

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Let three random samples of sizes n1 = 20, n2 = 10, and n3 = 8 be taken from a population with mean μ and variance σ2. Let S2/1, S2/2, and S2/3 be the sample variances. Show that S2 = (20S2/1 + 10S2/2 + 8S2/3)38 is an unbiased estimator of σ2.

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Applied Statistics And Probability For Engineers

ISBN: 9781118539712

6th Edition

Authors: Douglas C. Montgomery, George C. Runger

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Question Posted: Apr 05, 2010 02:37 AM

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Let three random samples of sizes n1 = 20, n2 = 10, and n3 = 8 be

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Applied Statistics And Probability For Engineers

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