question 17

Manisha is a seasoned researcher who specializes in the science of sleep. She is interested in the effects of Melatonin on both length and quality of sleep, so she conducts a well-designed, controlled experiment on randomly chosen participants. Half of the participants are given 5mg of Melatonin before bedtime, while half are given a placebo. After verifying her assumptions, she calculates a 99% confidence interval of (-0.83, 1.19) for the difference in average number of hours slept per night between the treatment group (which received Melatonin) and the control group (which received the placebo). Which of the following statements are accurate, regarding this interval? Select one or more: Da. If we were to repeat this experiment with many different random samples, we would expect about 99% of the arising confidence intervals to contain the true mean difference in average hours slept per night with and without Melatonin. Ob. It is reasonable to conclude that there is a significant difference between average hours slept per night with Melatonin and average hours slept per night without Melatonin. Oc. This is an observational study, so no confidence interval can be calculated. d. 99% of future samples will give a difference in sample mean between the treatment group and the control group that fell into the interval (-0.83, 1. 19). De. There is a 99% chance that the true average difference in hours slept between the treatment group and the control group is between -0.83 and 1.19 hours. Of. We cannot conclude that there is a difference between average hours slept per night with Melatonin and average hours slept per night without Melatonin. Og. We believe with 99% confidence that the true mean difference in average hours of sleep in a night between those who take 5mg of Melatonin before bedtime and those who don't is between -0.83 and 1.19 hours