Question

A team of health research wants to investigate whether having regular lunch break improves working adults’ sleep. A group of 103 adults with a full-time job were recruited in the study, they reported average hours of sleep in the past week, committed to having a 1-hour, out-of-office, work-free lunch break each day for 3 months, and, at the end of the study, reported average hours of sleep in the past week. The mean difference in hours of sleep before and after the study was 3 with a standard deviation of 0.9. Which one of the following statements is INCORRECT? (Set alpha level at 0.05.)

A team of health research wants to investigate whether having regular lunch break improves working adults' sleep. A group of 103 adults with a full-time job were recruited in the study, they reported average hours of sleep in the past week, committed to having a 1-hour, out-of-office, work-free lunch break each day for 3 months, and, at the end of the study, reported average hours of sleep in the past week. The mean difference in hours of sleep before and after the study was 3 with a standard deviation of 0.9. Which one of the following statements is INCORRECT? (Set alpha level at 0.05.) The null hypothesis is that hours of sleep remain the same before and after the study. The degrees of freedom is 102. The decision should be to reject the null hypothesis. The obtained test statistic is 3.383.

Answer 1

The statistical software output for this problem is:

One sample T summary hypothesis test:

μ : Mean of population
H₀ : μ = 0
H_A : μ > 0

Hypothesis test results:

Mean	Sample Mean	Std. Err.	DF	T-Stat	P-value
μ	3	0.088679635	102	33.829639	<0.0001

Hence,

p - value < 0.0001 so we reject Ho.

Option C is correct.