Question

(1 point) A 90% confidence interval for the difference between the means of two independent populations with unknown population standard deviations is found to be (-0.2, 5.4). Which of the following statements is/are correct? CHECK ALL THAT APPLY. A. The standard error of the difference between the two observed sample means is 2.6. B. A two-sided two-sample t-test testing for a difference between the two population means is rejected at the 10% significance level. C. A two-sided two-sample t-test testing for a difference between the two population means is not rejected at the 10% significance level. D. A two-sided paired t-test testing for a difference between the two population means is rejected at the 10% significance level. E. A two-sided paired t-test testing for a difference between the two population means is not rejected at the 10% significance level. F. None of the above.

Answer 1

ANSWER: (B)

Here sample size is not known and the the groups are independent so it is not a paired t test.

Hence option 'A' , 'D' and 'E' is not correct.

Given confidence interval is (-0.2,5.4)

The above confidence interval contains null hypothesis value zero.

Hence there is no difference between two means.

Therefore we reject the difference between means