The statistic n 1 s 2 σ 2 has a chi squared

2. The statistic ( n - 1) s 2 / σ 2 has a chi-squared distribution with n - 1 degrees of freedom if:
a. the sample has a Student t -distribution with degrees of freedom equal to n -
b. the sample is normally distributed with variance equal to s 2
c. the population is normally distributed with variance equal to σ 2
d. All of these choices are true.
1.
.
.
3. Which of the following conditions is needed regarding the chi-squared test statistic for
the test of variance?
4. In a hypothesis test for the population variance, the hypotheses are H
0
: σ 2 = 30 vs.
H
1
: σ 2 < 30. If the sample size is 20 and the test is being carried out at the 5% level of
significance, the null hypothesis is rejected if:
5. In a hypothesis test for the population variance, the hypotheses are H
0
: σ 2 = 100 vs. H
σ 2 ≠ 100. If the sample size is 15 and the test is being carried out at the 10% level of
significance, the rejection region is:
1
: