u04a1– Related-Samples t Tests, ANOVA, and the Tukey HSD Test
Complete the following problems within this Word
document (do not submit other files). Show your work for problem sets that
require calculations. Ensure that your answer to each problem is clearly
visible. (You may want to highlight your answer or use a different type of color
to set it apart.)
· Criterion: Differentiate between independent samples,
repeated measures, and matched samples.
Independent samples test is used when we have to compare two independent samples, whether
their means of a metric are equal or not.
Repeated measures test is used when we have to perform a within-subjects test. We compare
the same metric across multiple time periods to check whether they have changed
over the time periods
Matched samples test is used when individuals
are paired from two independent groups to test the effect of an intervention.
·
Data:
o
Scenario A: A researcher wants to know whether men
or women spend more money at the movie concession stand. He asks the concession
clerk to identify the customer as male or female based on each saved receipt.
o
Scenario B: A CPR instructor wants to know if her
students are learning anything during her 90-minute training. She decides to
quiz her students at the beginning of class and again at the end of class.
·
Instruction: For each of the two
scenarios, identify whether independent samples, repeated measures, or matched
samples would be used. Explain how you can make the determination.
Scenario
A:
We use the independent samples test as we have two independent groups, men
and women and we are comparing the mean of amount spent at the concession stand
for the two groups
Scenario
B:
We use the repeated measures test, as we are comparing the quiz scores of a
sample of individual at two different times, i.e. beginning & end of class
· Criterion: Calculate a paired samples t
test in SPSS.
·
Data: Dr
Statistics wanted to test how her learners scored on a problem set when she
presented the problems sequentially versus when she presented the problems
randomly. She had 10 learners who scored the following:
Learner |
Sequential |
Random |
1 |
92 |
90 |
2 |
85 |
89 |
3 |
77 |
85 |
4 |
86 |
80 |
5 |
93 |
96 |
6 |
72 |
75 |
7 |
99 |
91 |
8 |
84 |
80 |
9 |
63 |
71 |
10 |
94 |
95 |
(Assessment
continues on next page.)
a.
Open SPSS and create a New DataSet.
b.
Click the Variable
View tab.
c.
Enter Sequential in row 1 and Random in row 2.
d.
Click the Data
View tab. Enter the data for each learner.
e.
In the Toolbar, click Analyze, select Compare
Means, and then select Paired-Samples
T Test.
f.
Click Sequential
and then click Arrow to send it over
to the Variable 1 box.
g.
Click Random
and then click Arrow to send it over
to the Variable 2 box.
h. Click OK and copy and paste the output into the
Word document below.
Paired Samples Statistics |
|||||
|
Mean |
N |
Std. Deviation |
Std. Error Mean |
|
Pair 1 |
Sequential |
84.50 |
10 |
11.088 |
3.506 |
Random |
85.20 |
10 |
8.456 |
2.674 |
Paired Samples
Correlations |
||||
|
N |
Correlation |
Sig. |
|
Pair 1 |
Sequential
& Random |
10 |
.872 |
.001 |
Paired Samples Test |
|||||||||
|
Paired Differences |
t |
df |
Sig. (2-tailed) |
|||||
Mean |
Std. Deviation |
Std. Error Mean |
95% CI of the Difference |
||||||
Lower |
Upper |
||||||||
Pair 1 |
Sequential
- Random |
-.700 |
5.559 |
1.758 |
-4.677 |
3.277 |
-.398 |
9 |
.700 |
· Criterion: Analyze a paired samples t test to
make a decision about the null hypothesis.
· Data: Use
the data from Problem Set 4.2.
Value of t = -0.398; critical t at the .01 α level = 2.821
No, the learners received sequenced problem sets score didn’t
significantly higher, as the t-statistic is less than one-tailed critical value
of t at the .01 α level.
We fail to reject the null hypothesis
· Criterion: Calculate a confidence interval based on the results of a independent
samples t test.
· Data: Use
the data from Problem Set 4.2.
· Instruction: Answer this: Based on that output, what is
the 95 percent confidence interval of the difference?
Independent Samples Test |
||||||||||
Related Questions in statistics category
Get Higher Grades Now
Tutors Online
Get Free Quote! 337 Experts Online |