Question

You have a company with 300 employees. Every year they have to go through a mandatory training which requires them to watch company made videos. You want to test if the employees will pay more attention to the videos if they include popular music (top 50 hits) or classical music. You select 40 employees to take part in a study where they watch the videos alone in a room and someone watching from a webcam counts how many times the employee looked away from the screen (you call this 'Distractions'). Half of the employees watch the videos with popular music and the other half watch with classical music. Use Popular music as group 1 and Classical music as group 2. The first 5 rows of the data are shown here.

a. What is the sample?


b. What is the population of interest?



c. What is the parameter you are interested in?  --- x1-x2 μ x μ1-μ2

There is also a summary of the data:

Group	Mean	Standard deviation
Popular	27.9	8.2
Classical	36.2	9.5

(For the numerical answers below, use 2 decimal places.)
d. The point estimate is:

e. The standard error is:

f. The 95% confidence interval goes from
to


g. Which group had more distractions in the sample?  --- Classical They were equal Popular

h. Would you say that there is a difference between the groups at the population level? Explain why or why not. If you say there is a difference explain which group has more distractions?

Answer 1