A researcher wishes to learn if a certain drug affects the reaction time of pilots to air traffic control
Question 1.
A researcher wishes to learn if a certain drug affects the reaction time of pilots to air traffic
control instructions. She obtained a sample of pilots and randomly divided them into two groups.
She then had one pilot group take the drug and used the second group as a control. Pilots were
given headsets and given commands from an air traffic controller. The reactions times for each
group of pilots is below.
The researcher is interested in learning if the drug reduces the reaction time. Her hypothesis is:
The mean reaction time in group A will be less than the mean in group B.
| Grp A | Grp B |
| Treated | Not Treated |
| 0.72 | 0.71 |
| 0.68 | 0.83 |
| 0.69 | 0.89 |
| 0.66 | 0.57 |
| 0.57 | 0.68 |
| 0.66 | 0.74 |
| 0.7 | 0.75 |
| 0.63 | 0.67 |
| 0.71 | 0.8 |
| 0.73 | 0.78 |
A t-test can be used to test the probability that the two means do not differ. The alternative is that
the reaction times from the group treated with the drug will not be less than that from the control
group.
This is a one-tailed test because the researcher is interested in if the drug decreased reaction
time. She is not interested in if the drug changed reaction time.
Assignment
Method
- (justify type of t-Test used)
- (justify type of test) [directional/non-directional]
- (identify alpha level used to test the null hypothesis)
Results
- Report descriptive statistics
<insert descriptive statistics table>
(discuss high points of statistical outcomes)
- Assess normality assumption
<insert histogram figure>
(discuss distributional symmetry)
- Assess equal variance assumption
(report and interpret results of Levene’s test)
(state null hypothesis)
<insert t-Test table>
(interpret results using the p-value)
(decision) [reject/retain null hypothesis]
Conclusion
(explain whether the drug decreased reaction time)
Question 2.
A researcher wishes to learn whether the GPA of incoming flight students may be a factor in the
number of flight hours the student completes in the first semester of college. The researcher has
collected the flight hours of a random sample of students in a group of high GPA students and
low GPA students.
| GPA | GPA |
| Low | High |
| 42 | 43 |
| 45 | 51 |
| 40 | 56 |
| 37 | 40 |
| 41 | 32 |
| 41 | 54 |
| 48 | 51 |
| 50 | 55 |
| 45 | 50 |
| 46 | 48 |
The researcher is testing whether GPA may be a factor in differences in flight time accumulated
in the first semester at college.
Their hypothesis is: The mean flight time of students with a low GPA is different than those
incoming students with a high GPA.
A t-test can be used to test the probability that the two means do not differ. The alternative is that
the means differ; one of them is greater than the other.
This is a two-tailed test because the researcher is interested in if GPA changes flight time.
Assignment
Method
- justify type of t-Test used
- justify type of test (directional/non-directional)
- identify alpha level used to test the null hypothesis
Results
- Report descriptive statistics
<insert descriptive statistics table>
<discuss high points of statistical outcomes>
- Assess normality assumption
<insert histogram figure>
<discuss distributional symmetry>
- Assess equal variance assumption
<report and interpret results of Levene’s test>
<state null hypothesis>
<insert t-Test table>
<interpret results using the p-value>
decision: (reject/retain null hypothesis]
Conclusion
(explain whether the number of flight hours differed between low and high GPA students)
Deliverable: Word Document
