5. Consider independent observations Xi ~ N(μ, σ?) for i I, , n. Suppose the ,o,...
Please show every step, thank you. Let Xi ~ N(μ, σ?), where ơỈ are known and positive for i-1, are independent. Let /- (a) Find the mean and variance of μ. (b) Compare μ to X,-n-Σί.i Xi as an estimator of μ. , n, and Xi, X, , E-1(1/o .m be the MLE of μ. Let Xi ~ N(μ, σ?), where ơỈ are known and positive for i-1, are independent. Let /- (a) Find the mean and variance of μ....
Xn are independent normal variates with the same variance σ, but with Suppose that Xi, X2, different means, Xi ~N(pbi,ơ2), for i-1.2, n where bi, b,.. k constants. (a) Find expressions for the MLE of μ and σ. You need not show the second derivative conditions (b) Suppose that b,-b2-...-bn. Find a simplified expression for the MLE of μ (c) Suppose that b,-b2-...-bn-1, and , is known. Find the MLE ofơ
4. Xi ,i = 1, , n are iid N(μ, σ2). (a) Find the MLE of μ, σ2. Are these unbiased estimators of μ and of σ2 respectively? Aside: You can use your result in (b) to justify your answer for the bias part of the MLE estimator of σ2 (b) In this part you will show, despite that the sample variance is an unbiased estimator of σ2, that the sample standard deviation is is a biased estimator of σ....
σ2). 6. Suppose X1, Yİ, X2, Y2, , Xn, Y, are independent rv's with Xi and Y both N(μ, All parameters μί, 1-1, ,n, and σ2 are unknown. For example, Xi and Yi muay be repeated measurements on a laboratory specimen from the ith individual, with μί representing the amount of some antigen in the specimen; the measuring instrument is inaccurate, with normally distributed errors with constant variability. Let Z, X/V2. (a) Consider the estimate σ2- (b) Show that the...
6. Suppose we have i.id. Xi, , Xn ~ N(μ, σ2). In the class, we learned that Σί i m(Xi-X) X2-1. Use this fact and answer the following questions. (a) Consider an estimator σ-c Σηι (Xi-X)2. Find its mean and variance.
3. Let Xi, , Xn be i.i.d. Lognormal(μ, σ2) (a) Suppose σ-1, prove that S-X(n)/X(i) is an ancillary statistics. (b) Suppose p 0, prove T-X(n) is a sufficient and complete statistics (c) Find a minimal sufficient statistics. 3. Let Xi, , Xn be i.i.d. Lognormal(μ, σ2) (a) Suppose σ-1, prove that S-X(n)/X(i) is an ancillary statistics. (b) Suppose p 0, prove T-X(n) is a sufficient and complete statistics (c) Find a minimal sufficient statistics.
DISTRIBUTION OF SAMPLE VARIANCE: Xn ~ N(μ, σ2), where both μ and σ are Problem 4 (25 points). Assume that Xi unknowin 1. Using the exact distribution of the sample variance (Topic 1), find the form of a (1-0) confidence interval for σ2 in terms of quantiles of a chi-square distribution. Note that this interval should not be symmetric about a point estimate of σ2. [10 points] 2. Use the above result to derive a rejection region for a level-o...
Let Xi, X2, , xn be independent Normal(μ, σ*) random variables. Let Yn = n Ση1Xi denote a sequence of random variables (a) Find E(%) and Var(%) for all n in terms of μ and σ2. (b) Find the PDF for Yn for all n c) Find the MGF for Y for all n
Let Xi, ,Xn be a sample from N(μ, σ2) and assume that both parameters are unknown. Consider testing where μοισ., are given constants. Use LRT to derive the general form of the intersection-union rejection region in its simplest form. Identify the exact dis- tribution of statistics in the intersection-union rejection region . Hint: Use the fact that when the sample is from a Normal distribution, sample mean and sample variance are statistically independent. Let Xi, ,Xn be a sample from...
A sample of 27 independent observations is taken from a normal distribution of unknown mean μ but known variance σ. 75.24. The sample mean is 5 is the width of the 98% confidence interval for μ? 4.42 and the sample variance is 41. What A sample of 27 independent observations is taken from a normal distribution of unknown mean μ but known variance σ. 75.24. The sample mean is 5 is the width of the 98% confidence interval for μ?...