Ifx, are normally distributed random variables with mean μ and variance σ2, then: and σ are...
Let X1 and X2 be independent random variables with mean μ and variance σ2. Suppose we have two estimators 1 (1) Are both estimators unbiased estimatros for θ? (2) Which is a better estimator?
1. (40) Suppose that X1, X2, Xn forms an independent and identically distributed sample from a normal distribution with mean μ and variance σ2, both unknown: 2nơ2 (a) Derive the sample variance, S2, for this random sample. (b) Derive the maximum likelihood estimator (MLE) of μ and σ2 denoted μ and σ2, respectively. (c) Find the MLE of μ3 (d) Derive the method of moment estimator of μ and σ2, denoted μΜΟΜΕ and σ2MOME, respectively (e) Show that μ and...
Suppose that a random variable is normally distributed with mean μ and variance σ2 and we draw a random sample of 5 observations from this distribution. What is the joint probability density function of the sample?
4. , XnER, let Eo,E1,..,Enbe independent normally distributed random Let Xo, X1, variables with common mean 0 and common variance σ2, and suppose Let a, b and σ2 be the maximum likelihood estimators of b,a and σ2 Note that these expressions involve only the training data(X1, Y the test data(xo. Yo) ,(xn%,). They omit The training error of our regression model is While its teat prediction) error is We know that In this exercise, we prove MSE (1+1+grt*)e* Note that...
Y2 Let Yİ'ý, variance σ. We showed in class that minimally sufficient estimators. Does this imply that y and S2 are MVUE estimators of μ and X, be independent and identically distributed random variables with mean μ and (Ση! YǐΣι Y?) is sufficient for (μ, σ2). These are also σ2 respectively? Explain why or why not.
Let X1,, Xn be independent and identically distributed random variables with unknown mean μ and unknown variance σ2. It is given that the sample variance is an unbiased estimator of ơ2 Suggest why the estimator Xf -S2 might be proposed for estimating 2, justify your answer
onsider the process Y, = Y + Σ|e, where Yo ~ (μ, σ2) and the e's are 0-mean, a stationary process? independent identically distributed random variables with variance 1. Is (Y How about the process ▽Yǐ = Yt-)t-1 ? Explain. onsider the process Y, = Y + Σ|e, where Yo ~ (μ, σ2) and the e's are 0-mean, a stationary process? independent identically distributed random variables with variance 1. Is (Y How about the process ▽Yǐ = Yt-)t-1 ? Explain.
Let X,, X,,...X be a random sample of size n from a normal distribution with parameters a. Derive the Cramer-Rao lower bound matrix for an unbiased estimator of the vector of parameters (μ, σ2). b. Using the Cramer-Rao lower bound prove that the sample mean X is the minimum variance unbiased estimator of u Is the maximum likelihood estimator of σ--σ-->|··( X,-X ) unbiased? c. Let X,, X,,...X be a random sample of size n from a normal distribution with...
3. Let Ya» . . . , Yn be independent normally distributed random variables with E(X) Gai and V(X)-1. Recall that the normal density with mean μ and variance σ given by TO 202 (a) Find the maximum likelihood estimator β of β (b) Show that ß is unbiased. (c) Determine the distribution of β (d) Recall that the likelihood ratio test of Ho : θ 02] L1] L2] θ° is to θ0 against H1: θ reject Ho if L(e)...
QUESTION 2 Let Xi.. Xn be a random sample from a N (μ, σ 2) distribution, and let S2 and Š-n--S2 be two estimators of σ2. Given: E (S2) σ 2 and V (S2) - ya-X)2 n-l -σ (a) Determine: E S2): (l) V (S2); and (il) MSE (S) (b) Which of s2 and S2 has a larger mean square error? (c) Suppose thatnis an estimator of e based on a random sample of size n. Another equivalent definition of...