ch.8 confidence interval mean

Question

question 13

A psychiatrist is interested in finding a 95% confidence interval for the tics per hour exhibited by children with Tourette syndrome. The data below show the tics in an observed hour for 10 randomly selected children with Tourette syndrome. Round answers to 3 decimal places where possible.

8

2

8

7

5

1

11

3

1

4

b. With 95% confidence the population mean number of tics per hour that children with Tourette syndrome exhibit is between _________ and______ .

c. If many groups of 10 randomly selected children with Tourette syndrome are observed, then a different confidence interval would be produced from each group. About_______  percent of these confidence intervals will contain the true population mean number of tics per hour and about ________  percent will not contain the true population mean number of tics per hour. 

 

Answer 1

Also note that we use t rather than z because we do not know our population variance.