In: Statistics and Probability
1. A researcher is interested in whether college students get enough sleep. She suspects that they get less than 8 hours of sleep on average. The sample mean (x¯) for 65 students was 7.08 hours. The standard deviation of number of hours students slept is s=1.8.
(a) Determine the null and alternative hypothesis for the test. What is the parameter in this study?
(b) The p-value for the test is <0.0001. Using a significance level of .05, write a one or two sentence conclusion in context of the problem.
(c) Calculate 95% confidence interval for µ, the mean number of hours college students sleep per night. Interpret the confidence interval. Be sure to use the word mean or average in your interpretation and don’t forget units. If you are doing the calculations by hand use t∗ = 1.998.
(d) Does your confidence interval support the results of the hypothesis test? Explain.