A group of students enroll in a behavioral statistics course taught by one of two professors....
A group of students enroll in a behavioral statistics course taught by one of two professors. The mean grade in Professor G's class is 84% (95% CI = 75%–93%), and the mean grade in Professor P's class is 75% (95% CI = 66%–84%).
(a) Is one confidence interval more precise? Explain.
Yes, the interval for Professor G's class is more precise. The mean for Professor G's class is higher.
Yes, the interval for Professor P's class is more precise. The mean for Professor P's class is farther from 95%.
No, the intervals have the same amount of precision. Both intervals use 95% confidence.
No, the intervals have the same amount of precision. The interval width for each confidence interval is ±9 points.
(b) Is one confidence interval associated with greater
certainty? Explain.
Yes, the interval for Professor G's class is associated with greater certainty. The mean for Professor G's class is higher.
Yes, the interval for Professor P's class is associated with greater certainty. The mean for Professor P's class is farther from 95%.
No, the intervals are associated with the same amount of certainty. Both intervals use 95% confidence.
No, the intervals are associated with the same amount of certainty. The interval width for each confidence interval is ±9 points.
Homework Answers
a) No, the intervals have the same amount of precision. The interval width for each confidence interval is ±9 points.
b) No, the intervals are associated with the same amount of certainty. Both intervals use 95% confidence.
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