The librarian at the New York City Public Library has asked her assistant for an interval estimate of the mean number of books checked out each day. The assistant took a sample and found the mean to be 880 books. She provides the librarian with an interval estimate of between 790 and 970 books checked out per day. An efficient, unbiased point estimate of the number of books checked out each day at the New York City Public Library is:
a. 790 c. 90
b. 880 d. None of these choices.
Q. 2The standardized residual is defined as:
a. residual multiplied by the square root of the standard error of estimate.
b. residual multiplied by the standard error of estimate.
c. residual divided by the square of the standard error of estimate.
d. residual divided by the standard error of estimate.
Q. 3The problem with relying on a point estimate of a population parameter is that:
a. it is virtually certain to be wrong.
b. it doesn't have the capacity to reflect the effects of larger sample sizes.
c. it doesn't tell us how close or far the point estimate might be from the parameter.
d. All of these choices are true.
Q. 4If the plot of the residuals vs. the predicted values resembles a straight line with non-zero slope, then the regression line fits well.
Indicate whether the statement is true or false
Q. 5If there are two unbiased estimators of a population parameter available, the one that has the smallest variance is said to be:
a. a biased estimator. c. consistent.
b. relatively efficient. d. relatively unbiased.
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