Question

Why is it important to compute confidence intervals for estimates of population means or percentages? A....

Why is it important to compute confidence intervals for estimates of population means or percentages?
A. Because every sample statistic is subject to error.
B. Because managers don’t like point estimates.
C. Because every sample statistic must be presented without error.
D. Because the sample statistic = the population parameter.

The calculated z or t value is inversely related to the size of the differences between two means or percentages (i.e., as the difference between two means or percentage increases, the calculated z or t decreases.
A. True
B. False

The calculated z or t value is inversely related to the size of the standard error (i.e., as standard error of the mean or percentage increases, the calculated z or t decreases.
A. True
B. False

Math   Statistics-And-Probability   
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Answer #1

The confidence interval provides a range of values in which sample statistics can lie so it is better than point estimate. Sample statistics provides an estimate to po;ulation parameter. It is not always equal to population parameter.

Correct option is

A. Because every sample statistic is subject to error.

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In calculating z or t value, the difference between two means or percentage comes into numerator so as the difference increase value of z or t will also increase.

Hence, correct option is

B: False

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In calculating z or t value, the standard error comes into denominator so as the standard error increases value of z or t will decreases.

Hence, correct option is

A. True

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