You can use both the t statistic and the z statistic to test

You can use both the t statistic and the z statistic to test hypotheses about the mean of a population. The test that uses the t statistic is typically referred to as a t test, while the test that uses the z statistic is commonly called a z test. Which of the following statements are true of the t statistic and the t distribution? Check all that apply. You should use a t test if the population standard deviation is .

Solution

Which are true?

FALSE: The t distribution is the same for any sample size. (It depends on the degrees of freedom, hence sample size)

FALSE: The numerator of the t statistic is different than the numerator of the z statistic.

TRUE: The formula for the t statistic is tobt = (Xbar - u)/s(Xbar).

TRUE: When you do not know the population standard deviation, you can use the t statistic, assuming all relevant assumptions are satisfied.

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You should use the t test if the population standard deviation is UNKNOWN. [ANSWER]