Suppose that Y₁, Y2, ..., Ym and X₁, X₂,..., Xm are independent normally distributed random samples from populations with means μ₁ and μ, and variances σ₁² and σ₂², respectively. Is X - Y a consistent estimator of μ₂ - μ₁?
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- Suppose that there are two borrowing strategies from a commercial bank as short-term and long-term. We have two small samples (n1=8 and n2=8) and sampled populations are normal. Standard deviation for the first sample is 200 and for the second one is 150. The researcher wants to determine whether the variation in the customers preferring short-term borrowing differs from the variation in the customers preferring long-term borrowing. (Use 0.10 significance level)Suppose we have two SRSS from two distinct populations and the samples are independent. We measure the same variable for both samples. Suppose both populations of the values of these variables are normally distributed but the means and standard deviations are unknown. For purposes of comparing the two means, we use (a) Two-sample t procedures (b) Matched pairs t procedures (c) z procedures (d) The least-squares regression line (e) None of the above. The answer isSuppose a data set from a bike share company contains the number of daily bike rentals at each of 6 stations for the 23 weekdays of a particular month, i.e. we have Yij for i = 1, ..., 23 and j 1,...6. Write down a hierarchical normal model that can be used to estimate the mean number of bike rentals at each station. You can assume that the unknown variance o? of the number of bike rentals is the same for each station.
- Two computer companies are offering new software to universities. Let X and Y denote the number of software installed in three major universities by these two companies. Suppose that the variance of X is 539, the variance of Yis 754, and the covariance of X and Yis 183.50. a) Calculate the correlation coefficient (p) Select one: a. 0.287 b. 0.857 c. None of the answers d. 0.9281) Suppose the following model y; = B1 + u; Where is assumed to be normally distributed with mean zero and variance ơ² . Calculate analytically, following OLS technique, ß, and Var(ß,).There are two random variables X and Y, and their correlation coefficient pX,Y = 0.7. Now, we have two new random variables A = 2.5X+1 and B = 4Y+2. Please compute the correlation coefficient of A and B, PA,B Please round your answer to one decimal place.
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