Review of Statistics

If you wish to test the claim that the mean of the population is 28, the appropriate null hypothesis is

• μ = 28

• μ ≥ 28

• x > 28

• x = 28

H_o represents...

• the null hypothesis

• the alternative hypothesis

• the claim

• HO

The degrees of freedom for the t test for means are

• 1

• n

• n-1

• unnecessary

For the z-test, if the population standard deviation is unknown and n ≥ 30, one can substitute _______ for σ.

• t

• σ²

• n

• s

To test the claim that the proportion is less than .76, you would use a(n) _____________ test.

• right-tailed

• left-tailed

• two-tailed

• none of the above

To test the variance or standard deviation, you would use a(n) _____________ test.

• z

• t

• chi-square

• proportion

What test can be used to test the difference between two sample means when the population variances are known?

• z

• t

• chi-square

• proportion

If you hypothesize that there is a difference between means, this is represented as H₁: ___________.

• μ1 > μ2

• μ1 ≠ μ2

• μ1 < μ2

• μ1 = μ2

The z-value used for finding a 90% confidence interval is

• 1.65

• 1.96

• 2.33

• 2.58

When you are testing a sample mean, the ____ test is used when the population variance is known.

• z

• t

• chi-square

• proportion