Assignment 2: Tests of Significance
Throughout this assignment you will review mock studies. You will needs to follow the directions outlined in the section using SPSS and decide whether there is significance between the variables. You will need to list the five steps of hypothesis testing (as covered in the lesson for Week 6) to see how
every
question should be formatted. You will complete all of the problems. Be sure to cut and past the appropriate test result boxes from SPSS under each problem and explain what you will do with your research hypotheses.
All calculations should be coming from your SPSS
. You will need to submit the SPSS output file to get credit for this assignment. This file will save as a .spv file and will need to be in a single file. In other words, you are not allowed to submit more than one output file for this assignment.
The five steps of hypothesis testing when using SPSS are as follows:
State your research hypothesis (H
1
) and null hypothesis (H
0
).
Identify your significance level (.05 or .01)
Conduct your analysis using SPSS.
Look for the valid score for comparison. This score is usually under ‘Sig 2-tail’ or ‘Sig. 2’. We will call this “p”.
Compare the two and apply the following rule:
If “p” is < or = significance level, than you reject the null.
Be sure to explain to the reader what this means in regards to your study. (Ex: will you recommend counseling services?)
* Be sure that your answers are clearly distinguishable. Perhaps you bold your font or use a different color.
This assignment is due no later than Sunday of Week 6 by 11:55 pm ET. Save the file in the following format: [your last name_SOCI332_A2]. The file must be a word file.
t Tests
t Test for a Single Sample (20 points)
Open SPSS
Enter the number of activities of daily living performed by the depressed clients studied in #1 in the Data View window.
In the Variable View window, change the variable name to “ADL” and set the decimals to zero.
Click Analyze
à
Compare Means
à
One-Sample T test
à
the arrow to move “ADL” to the Variable(s) window.
Enter the population mean (17) in the “Test Value” box.
Click OK.
1.
Researches are interested in whether depressed people undergoing group therapy will perform a different number of activities of daily living after group therapy. The researchers have randomly selected 12 depressed clients to undergo a 6-week group therapy program.
Use the five steps of hypothesis testing to determine whether the average number of activities of daily living (shown below) obtained after therapy is significantly different from a mean number of activities of 17 that is typical for depressed people. (Clearly indicate each step).
Test the difference at the .05 level of significance and at the .01 level (in SPSS this means you change the “confidence level” from 95% to 99%).
As part of Step 5, indicate whether the behavioral scientists should recommend group therapy for all depressed people based.
Assignment 2 Tests of SignificanceThroughout this assignmen.docx
1. Assignment 2: Tests of Significance
Throughout this assignment you will review mock studies. You
will needs to follow the directions outlined in the section using
SPSS and decide whether there is significance between the
variables. You will need to list the five steps of hypothesis
testing (as covered in the lesson for Week 6) to see how
every
question should be formatted. You will complete all of the
problems. Be sure to cut and past the appropriate test result
boxes from SPSS under each problem and explain what you will
do with your research hypotheses.
All calculations should be coming from your SPSS
. You will need to submit the SPSS output file to get credit for
this assignment. This file will save as a .spv file and will need
to be in a single file. In other words, you are not allowed to
submit more than one output file for this assignment.
The five steps of hypothesis testing when using SPSS are as
follows:
State your research hypothesis (H
1
) and null hypothesis (H
0
).
Identify your significance level (.05 or .01)
Conduct your analysis using SPSS.
Look for the valid score for comparison. This score is usually
under ‘Sig 2-tail’ or ‘Sig. 2’. We will call this “p”.
Compare the two and apply the following rule:
If “p” is < or = significance level, than you reject the null.
Be sure to explain to the reader what this means in regards to
your study. (Ex: will you recommend counseling services?)
2. * Be sure that your answers are clearly distinguishable. Perhaps
you bold your font or use a different color.
This assignment is due no later than Sunday of Week 6 by 11:55
pm ET. Save the file in the following format: [your last
name_SOCI332_A2]. The file must be a word file.
t Tests
t Test for a Single Sample (20 points)
Open SPSS
Enter the number of activities of daily living performed by the
depressed clients studied in #1 in the Data View window.
In the Variable View window, change the variable name to
“ADL” and set the decimals to zero.
Click Analyze
à
Compare Means
à
One-Sample T test
à
the arrow to move “ADL” to the Variable(s) window.
Enter the population mean (17) in the “Test Value” box.
Click OK.
1.
Researches are interested in whether depressed people
undergoing group therapy will perform a different number of
activities of daily living after group therapy. The researchers
have randomly selected 12 depressed clients to undergo a 6-
week group therapy program.
Use the five steps of hypothesis testing to determine whether
3. the average number of activities of daily living (shown below)
obtained after therapy is significantly different from a mean
number of activities of 17 that is typical for depressed people.
(Clearly indicate each step).
Test the difference at the .05 level of significance and at the .01
level (in SPSS this means you change the “confidence level”
from 95% to 99%).
As part of Step 5, indicate whether the behavioral scientists
should recommend group therapy for all depressed people based
on evaluation of the null hypothesis at both levels of
significance.
CLIENT
AFTER THERAPY
A
18
B
14
C
11
D
25
E
24
F
17
G
14
H
10
I
23
J
11
4. K
22
L
19
t Test for Dependent Means (20 points)
Open SPSS
Enter the number of activities of daily living performed by the
depressed clients studied in Problem 2 in the Data View
window. Be sure to enter the “before therapy” scores in the first
column and the “after therapy” scores in the second column.
In the Variable View window, change the variable name for the
first variable to “ADLPRE” and the variable name for the
second variable to “ADLPOST”. Set the decimals for both
variables to zero.
Click Analyze
à
Compare Means
à
Paired-Samples T Test
à
the arrow to move “ADLPRE” to the Paired Variable(s) window
à
“ADLPOST” and then click the arrow to move the variable to
the Paired Variable(s) window.
Click OK.
2.
Researchers are interested in whether depressed people
undergoing group therapy will perform a different number of
activities of daily living before and after group therapy. The
researchers have randomly selected 8 depressed clients in a 6-
week group therapy program.
5. Use the five steps of hypothesis testing to determine whether
the observed differences in numbers of activities of daily living
(shown below) obtained before and after therapy are
statistically significant at the .05 level of. (Clearly indicate
each step).
As part of Step 5, indicate whether the researchers should
recommend group therapy for all depressed people based on
evaluation of the null hypothesis at the .05 level of significance
and calculate the measure of association.
CLIENT
BEFORE THERAPY
AFTER THERAPY
A
11
17
B
7
12
C
10
12
D
13
21
E
9
16
F
8
17
G
13
17
H
6. 12
8
The t Test for Independent Samples (20 points)
Once you have entered the data, click on
Analyze
, then on
Compare Means
, and then click on
Independent-Samples T Test
…
A dialog box will appear, with your variables (student,
condition, score) on the left. Your options are (a) move one or
more variables into the “Test Variable(s)” box to select your
dependent variables(s) and (b) move one of your variables into
the “Grouping Variable” box to select the independent variables
(or identify the groups to be compared).
Make “?” the dependent variable by moving it to the “Test
Variable(s)” box. Then make “?” your independent variable by
moving it to the “Grouping Variable” box. Now, the “Define
Groups” button is functioning, click on
Define Groups
and another dialog box appears. Here you must specify the two
values of the condition variable that represent the two groups
you are comparing.
Click
in the box next to Group 1 and type the number 1, then
click
in the box next to Group 2 and type the number 2. Now you
can click
Continue
to return to the “Independent-Samples T Test” dialog box, and
7. click on
OK
to run the analysis.
3.
Six months after an industrial accident, a researcher has been
asked to compare the job satisfaction of employees who
participated in counseling sessions with the satisfaction of
employees who chose not to participate.
The scores on a job satisfaction inventory for both groups are
listed in the table below.
Use the five steps of hypothesis testing
to determine whether the job satisfaction scores of the group
that participated in counseling are statistically higher than the
scores of employees who did not participate in counseling at the
.01 level of significance.
As part of Step 5, indicate whether the researcher should
recommend counseling as a method to improve job satisfaction
following industrial accidents based on evaluation of the null
hypothesis and calculate the measure of association.
NOTE: Do not forget to give a numeric value for those who
participated in counseling (e.g. 0) and those who did not
participate in counseling (e.g. 1).
PARTICIPATED IN COUNSELING
DID NOT PARTICIPATE IN COUNSELING
36
38
39
36
41
8. 36
36
32
37
30
35
39
37
41
39
35
42
33
ANOVA (20 points)
Open SPSS
Analyze the data for #1. Remember that SPSS assumes that all
the scores in a row are from the same participant. In this study,
there are 15 participants divided into three groups of five.
Therefore, each of the 15 participants will be described by two
variables, type of therapy and the number of activities of daily
living performed.
If “1” represents the group receiving individual therapy for 1
hour every 2 weeks, “2” represents the group receiving 1 hour
of individual therapy each week, and “3” indicates the group
receiving 2 hours of individual therapy each week, the first
participant will be described by entering “1” in the top cell of
the first column in the Data View window and “16” in the top
cell of the second column to indicate that the participant
underwent 1 hour of therapy every 2 weeks and performed 16
activities of daily living. The second participant will be
described by “1” and “15”, and the third by “1” and “18”.
9. When the two variables have been entered for the five
participants in this group, repeat the process for participants
who underwent 1 hour of individual therapy each week, using
“2” to describe their therapy group. When the two variables for
the five participants in this group have been entered, repeat the
process for Group 3, entering “3” in the first column. In the
Variable View window, change the first variable name to
“THERAPY” and the second to “ADL” and set the decimals for
both to zero.
Click Analyze
à
Compare Means
à
One-Way ANOVA
à
Since “THERAPY” is already selected, you can click the arrow
to move the variable to the Factor window. Select “ADL” and
click the arrow to move the variable to the Dependent List
window, which instruct SPSS to conduct the analysis of
variance on the number of activities performed.
Click “Options” and click the box labeled “Descriptive” to
obtain descriptive statistics.
Click Continue.
Click OK.
4.
Keep in mind that the clients in Group 1 will receive 1 hour of
therapy every 2 weeks, the clients in Group 2 will receive 1
hour of therapy every week, and the clients in Group 3 will
receive 2 hours of therapy every week.
Use the five steps of hypothesis testing to determine whether
the observed differences in the number of activities in the
10. following table performed by the three groups are statistically
significant at the .05 level of significance.
Clearly indicate each of the five steps.
CLIENT
GROUP 1
GROUP 2
GROUP 3
1
16
21
24
2
15
20
21
3
18
17
25
4
21
23
20
5
19
19
22
5.
11. Describe the circumstances under which you should use
ANOVA instead of t tests, and explain why t tests are
inappropriate in these circumstances.
Chi-Square (20 points)
Chi-Square
SPSS instructions:
Chi-Square Test for Goodness of Fit:
Open SPSS
Remember that SPSS assumes that all the scores in a row are
from the same participant. In the study presented in #1, there
are 20 students, some of whom have been suspended for
misbehavior. The primary conflict-resolution style used by each
student is also entered. [Ignore the first variable in this
analysis.]
When you have entered the data for all 20 students, move to the
Variable View window and change the first variable name to
“SUSPEND” and the second to “STYLE”. Set the number of
decimals for both variables to zero.
Click Analyze
à
Non-Parametric Tests
à
Chi-Square
Click the variable “STYLE” and then the arrow next to the box
labeled “Test Variable List” to indicate that the chi-square for
goodness of fit should be conducted on the conflict-resolution
style variable.
Note that “All categories equal” is the default selection in the
“Expected Values” box, which means that SPSS will conduct
12. the goodness of fit test using equal expected frequencies for
each of the four styles, in other words, SPSS will assume that
the proportions of students each style are equal.
Click OK.
Chi-Square Test for Independence:
Open SPSS
For #2, you need to add the variable “SUSPEND” to the
analysis. Remember that in this problem, we are interested in
whether there was an association between conflict-resolution
style and having been suspended from school for misbehavior.
Since the analysis will involve two nominal variables, the
appropriate test is a chi-square test for independence.
Click Analyze
à
Descriptive Statistics
à
Crosstabs
Since “SUSPEND” is already selected, click the arrow next to
the box labeled “Rows.”
Click the variable “STYLE” and click the arrow next to the box
labeled “Columns.”
Click “Statistics” and click the box labeled “Chi-Square.”
Click Continue.
Click “Cells” and click the box labeled “Expected.”
Click Continue.
Click OK.
6.
The following table includes the primary method of conflict
resolution used by 20 students.
Method
13. Aggressive
Manipulative
Passive
Assertive
N
of Students
8
2
2
8
a.
Following the five steps of hypothesis testing, conduct the
appropriate chi-square test to determine whether the observed
frequencies are significantly different from the frequencies
expected by change at the .05 level of significance. Clearly
identify each of the five steps.
7.
Next, researchers categorized the students based on the primary
method of conflict resolution used and whether the student had
been suspended from school for misbehavior. These data are
presented below.
Method
Suspended
Aggressive
Manipulative
Passive
Assertive
Total
Yes
7
14. 1
1
1
10
No
1
1
1
7
10
Total
8
2
2
8
20
a.
Following the five steps of hypothesis testing, conduct the
appropriate chi-square test to determine whether the observed
frequencies are significantly different from the frequencies
expected by change at the .05 level of significance. Clearly
identify each of the five steps.
b.
Calculate the measure of association.
8.
Believing that assertiveness is the most effective method of
conflict resolution, the researchers categorized students so that
the aggressive, manipulative, and passive categories were
15. combined. These data are presented in the table below.
Conflict Resolution
Suspension from School
Assertive
Other
Total
Yes
1
9
10
No
6
4
10
Total
7
13
20
a.
Following the five steps of hypothesis testing, conduct the
appropriate chi-square test to determine whether the observed
frequencies are significantly different from the frequencies
expected by change at the .05 level of significance. Clearly
identify each of the five steps.
b.
Explain your results.