Confidence Intervals and Introduction to Hypothesis Testing

1) Calculate a 95% and 99% confidence interval for the following data set. Note: this is a sample. Show your steps including the mean, z-score, standard deviation, and standard error that you use.

12

10

18

16

11

10

9

17

6

13

10

20

21

24

18

17

19

12

11

10

2) In an experimental treatment, a random individual scores 51 on a measurement. People in general are normally distributed with a mean of 37 and a standard deviation of 7. The researcher predicts that the treatment will create an effect on the subject, but does not specify if the measurement will increase or decrease. Using a 5% significance level (p < .05), what conclusions should this researcher make about the treatment. Utilize the five-step hypothesis testing process and show all of your work.