Homework SourseAn Internet service provider is interested in testing to see
An Internet service provider is interested in testing to see if there is a difference in the mean weekly connect time for users who come into the service through a dial-up line, DSL, or cable Internet. To test this, the ISP has selected random samples from each category of user and recorded the connect time during a week period. The following data were collected:
Based upon these data and a significance level of 0.05, which of the following statements is true?
| Dial Up | DSL | Cable |
| 19.2 | 40.6 | 39.5 |
| 17.7 | 40 | 42.3 |
| 17.2 | 41.5 | 47 |
| 18.9 | 30.5 | 45.4 |
| 26.9 | 46.8 | 41.1 |
| 22.6 | 43.2 | |
| 31.2 | 39.9 | |
| 41.9 | ||
| 49.3 |
Solution
Given a=0.05, the critical value is F(0.95, df1=2, df2=18) =3.55 (from F table)
Answer:
All of the above are true.
| Mean | n | Std. Dev | |
| 21.96 | 7 | 5.291 | Dial Up |
| 39.88 | 5 | 5.896 | DSL |
| 43.29 | 9 | 3.315 | Cable |
| 35.37 | 21 | 10.771 | Total |
