Question

A clinical trial was conducted to test the effectiveness of a drug for treating insomnia in older subjects. Before​ treatment,1313 subjects had a mean wake time of

103.0103.0 min. After​ treatment, the 1313 subjects had a mean wake time of 93.893.8 min and a standard deviation of 20.220.2 min. Assume that the

1313 sample values appear to be from a normally distributed population and construct a 9999​% confidence interval estimate of the mean wake time for a population with drug treatments. What does the result suggest about the mean wake time of 103.0103.0 min before the​ treatment? Does the drug appear to be​ effective?Construct the 9999​% confidence interval estimate of the mean wake time for a population with the treatment. nothing min less than<muμless than<nothing min ​(Round to one decimal place as​ needed.) What does the result suggest about the mean wake time of 103.0103.0 min before the​ treatment? Does the drug appear to be​ effective? The confidence interval ▼ the mean wake time of 103.0103.0 min before the​ treatment, so the means before and after the treatment ▼ This result suggests that the drug treatment ▼ a significant effect.

Answer 1

df = 13 - 1 = 12

At 99% confidence level, the critical value is t^* = 3.055

The 99% confidence interval is

The confidence interval contains the mean wake time of 103.0 min before the treatment, so the means before and after the treatment are equal. This result suggests that the drug treatment has not a significant effect.