1. ) An instructor believes that students do not retain as muchinformation from a lecture on a Friday compared to a Monday. Totest this belief, the instructor teaches a small sample of collegestudents some preselected material from a single topic onstatistics on a Friday and on a Monday. All students received atest on the material. The differences in exam scores for materialtaught on Friday minus Monday are listed in the followingtable.
DifferenceScores
(Friday ? Monday) |
|---|
+3.3 |
+4.5 |
+6.3 |
+1.1 |
?1.7 |
(a) Find the confidence limits at a 95% CI for these relatedsamples. (Round your answers to two decimal places.)
to
(b) Can we conclude that students retained more of the materialtaught in the Friday class?
Yes, because 0 lies outside of the 95% CI.No, because 0 iscontained within the 95% CI.
2;) Listening to music has long been thought to enhanceintelligence, especially during infancy and childhood. To testwhether this is true, a researcher records the number of hours thateight high-performing students listened to music per day for 1week. The data are listed in the table.
MusicListening Per
Day (in hours) |
|---|
| 4.1 |
| 4.8 |
| 4.9 |
| 3.7 |
| 4.3 |
| 5.6 |
| 4.1 |
| 4.3 |
(a) Find the confidence limits at a 95% CI for thisone-independent sample. (Round your answers to two decimalplaces.)
to hours per day
(b) Suppose the null hypothesis states that students listen to 3.5hours of music per day. What would the decision be for a two-tailedhypothesis test at a 0.05 level of significance?
Retain the null hypothesis because the value stated in the nullhypothesis is within the limits for the 95% CI.Reject the nullhypothesis because the value stated in the null hypothesis isoutside the limits for the 95% CI. Rejectthe null hypothesis because the value stated in the null hypothesisis within the limits for the 95% CI.Retain the null hypothesisbecause the value stated in the null hypothesis is outside thelimits for the 95% CI.
