Continuation for more questions - 1-3 answers (but included for reference) Can pleasant aromas help a student learn better? Hirsch and Johnston, of the Smell & Taste Treatment and Research Foundation, Chicago, asked subjects to work through a set of two pencil and paper mazes six times; three times while wearing a floral-scented mask and three times with an unscented mask. Testers measured the length of time it took subjects to complete each of the six trials. The improvement in completion times, expressed as the percentage change in speed of completion from the first trial to the third trial for each maze, was recorded. (Negative values indicate no improvement with completion times longer for the third trial.). The researchers wanted to determine whether there was more of an improvement in completion times, on average, when wearing a floral-scented mask. Data: % Unscented % Scented 33.07 43.13 9.31 -3.66 28.41 42.86 15.26 30.65 21.86 16.42 7.37 16.37 20.44 3.17 -23.43 27.06 -3.35 27.25 32.78 -0.17 22.77 37.3 -6.77 35.89 19.64 22.14 28.69 7.85 9.05 -19.08 11.06 43.12 17.48 29.16 -10.23 -26.72 15.43 38.52 -22.51 12.44 -4.62 26.04 1. Clearly indicate why a paired t-test should be used in this analysis. Then produce the appropriate t-test output using Excel (with α = 0.05). ALREADY ANSWERED, INCLUDED FOR REFERENCE. 2. What would be the appropriate hypotheses for this test? Explain any symbols used. ALREADY ANSWERED, INCLUDED FOR REFERENCE. 3. The statistical report said, “The test provided weak evidence for more improvement with the floral scent.” Do you agree with the report’s conclusion? Provide details of your decision rule and conclusion. ALREADY ANSWERED, INCLUDED FOR REFERENCE. 4. Outline the necessary assumptions for the validity of the test in context. 5. Find the differences in improvement for each subject (scented – unscented) and use Excel to draw a boxplot of this difference data to assist you to decide if the results of the test are valid. 6. If the mean of the difference data xD = 8.95 with a standard deviation SD = 23.88, find a 99% confidence interval for the mean difference (scented – unscented) in improvement in completion times. Provide an interpretation of this interval in the context of possible extra improvement with floral scent
Continuation for more questions - 1-3 answers (but included for reference)
Can pleasant aromas help a student learn better? Hirsch and Johnston, of the Smell & Taste Treatment and Research Foundation, Chicago, asked subjects to work through a set of two pencil and paper mazes six times; three times while wearing a floral-scented mask and three times with an unscented mask. Testers measured the length of time it took subjects to complete each of the six trials. The improvement in completion times, expressed as the percentage change in speed of completion from the first trial to the third trial for each maze, was recorded. (Negative values indicate no improvement with completion times longer for the third trial.). The researchers wanted to determine whether there was more of an improvement in completion times, on average, when wearing a floral-scented mask.
Data:
| % Unscented | % Scented |
| 33.07 | 43.13 |
| 9.31 | -3.66 |
| 28.41 | 42.86 |
| 15.26 | 30.65 |
| 21.86 | 16.42 |
| 7.37 | 16.37 |
| 20.44 | 3.17 |
| -23.43 | 27.06 |
| -3.35 | 27.25 |
| 32.78 | -0.17 |
| 22.77 | 37.3 |
| -6.77 | 35.89 |
| 19.64 | 22.14 |
| 28.69 | 7.85 |
| 9.05 | -19.08 |
| 11.06 | 43.12 |
| 17.48 | 29.16 |
| -10.23 | -26.72 |
| 15.43 | 38.52 |
| -22.51 | 12.44 |
| -4.62 | 26.04 |
1. Clearly indicate why a paired t-test should be used in this analysis. Then produce the appropriate t-test output using Excel (with α = 0.05). ALREADY ANSWERED, INCLUDED FOR REFERENCE.
2. What would be the appropriate hypotheses for this test? Explain any symbols used. ALREADY ANSWERED, INCLUDED FOR REFERENCE.
3. The statistical report said, “The test provided weak evidence for more improvement with the floral scent.” Do you agree with the report’s conclusion? Provide details of your decision rule and conclusion. ALREADY ANSWERED, INCLUDED FOR REFERENCE.
4. Outline the necessary assumptions for the validity of the test in context.
5. Find the differences in improvement for each subject (scented – unscented) and use Excel to draw a boxplot of this difference data to assist you to decide if the results of the test are valid.
6. If the mean of the difference data xD = 8.95 with a standard deviation SD = 23.88, find a 99% confidence interval for the mean difference (scented – unscented) in improvement in completion times. Provide an interpretation of this interval in the context of possible extra improvement with floral scent.
Step by step
Solved in 5 steps with 3 images
