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QUESTION 25 Suppose professor finds that for 16 randomly selected students the time needed to complete...

QUESTION 25

Suppose professor finds that for 16 randomly selected students the time needed to complete an assignment had a sample mean of 65 minutes and a sample standard deviation of 40 minutes. The 98% confidence interval estimate for the population mean is:

QUESTION 26

After estimating the interval in the previous question, we can interpret it as:

a.

We are 98% confident that the sample mean falls into the estimated interval.

b.

We are 98% confident that the estimated interval contains the population mean.

c.

We are 98% confident that the estimated interval contains the sample mean.

d.

We are 98% confident that the true mean falls into the estimated interval.

QUESTION 27

For two unbiased point estimators of the same parameter, the point estimator with the smaller variance is said to have

a.

smaller relative efficiency

b.

smaller relative consistency

c.

greater relative efficiency

d.

greater relative consistency

QUESTION 28

When sample size gets larger, an unbiased point estimator gets closer and closer to the parameter it estimates. This property is called:

a.

consistency

b.

relative estimation

c.

efficiency

d.

unbiased efficiency

QUESTION 29

X-bar is an unbiased estimator of µ because

a.

standard error of X-bar equals sigma/ square root of n

b.

expected value of X-bar equals µ

c.

shape of distribution of X-bar is normal.

d.

Expected value of X-bar is greater than 1.

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