A researcher determined the size sample necessary to estimate two population means Y and Z. The indicated sizes were 200 to estimate Y and 300 to estimate Z with the specified degrees of confidence and precision. The researcher decided therefore to use a sample of size 250 . Assuming the estimates of the population standard deviation were correct
a. the estimate of Y is more precise than desired while that for Z is less precise than desired.
b. the estimate of Y is less precise than desired while that for Z is more precise than desired.
c. Y is estimated with exactly the specified degree of precision while Z is estimated less precisely than desired.
d. Z is estimated with exactly the specified degree of precision while Y is estimated less precisely than desired.
e. Both Y and Z are estimated with the exact specified degree of precision.
Question 2
If the sample standard deviation turns out to be larger than the estimated population standard deviation, the confidence interval to estimate a population mean will be __________ planned.
a. Narrower than
b. Wider than
c. The same as
d. As precise as
e. None of the above
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