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4. Let X1,X2, x 2) distribution, and let sr_ Ση:1 (Xi-X)2 and S2 n-l Σηι (Xi-X)2 be the estimators of σ2. (i) Show that the MSE of S is smaller than the MSE of S2 (ii) Find ElvS2] and suggest an unbiased estimator of σ. n be a random sample from N (μ, σ
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TOPIC: Comparison between sample variances (with divisor 'n' and (n-1)) according to their MSE and finding an unbiased estimator of the population sd.

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