Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
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University of Phoenix Course Material
Problem of Practice Mock Study Development Template: Week Five
Instructions:
Run a one-way independent ANOVA in SPSS® using your mock study data. Complete each of the
associated tasks below. Refer to Section 12.6, “Comparing Several Means Using SPSS Statistics,” in Ch.
12, “GLM 1: Comparing Several Independent Means,” of Discovering Statistics Using IBM SPSS
Statistics.
1) Create a series of tables that depict your results. Do not simply paste your output from SPSS®; rather,
prepare each table to demonstrate your ability to format according to APA guidelines.
Table 1
Descriptives
dimensions
95% Confidence Interval for
Mean
N
Maine
Behavioral Clinic
Mercy Clinic
Spring Harbor
Clinic
Total
Mean
Std. Deviation Std. Error
Lower Bound
Upper Bound Minimum Maximum
50
37.7050
6.84778
.96842
35.7589
39.6511
20.75
55.38
50
50
49.0075
40.0075
6.03616
7.56277
.85364
1.06954
47.2920
37.8582
50.7230
42.1568
34.88
21.63
66.00
55.38
150
42.2400
8.37585
.68389
40.8886
43.5914
20.75
66.00
Table 2
Test of Homogeneity of Variances
Levene
Statistic
dimensions Based on Mean
df1
df2
Sig.
1.098
2
147
.336
Based on
Median
1.085
2
147
.340
Based on
Median and with
adjusted df
1.085
2
142.203
.341
Based on
trimmed mean
1.096
2
147
.337
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Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
Table 3
ANOVA
dimensions
Between Groups
Within Groups
Total
Sum of
Squares
df
3567.467
6885.612
10453.079
2
147
149
Mean Square
1783.733
46.841
F
38.081
Sig.
.000
Table 4
Robust Tests of Equality of Means
dimensions
Statistica
Welch
Brown-Forsythe
df1
43.328
38.081
df2
2
2
97.162
142.340
Sig.
.000
.000
a. Asymptotically F distributed.
2) Discuss the significance of the results.
Table 1 shows the Descriptives of the one-way ANOVA, which indicates that there are
significant differences among the groups with Maine Behavioral Clinic with a mean score of
37.7 compared with the other two clinics which had mean scores of 40.0 and 49.0. Table 2 is
summary of the Test of Homogeneity of Variances (Levene’s Test) which confirms the
differences in Table 2 (Field, 2013). Levene’s test yielded a p-value of 0.34 which when
compared with the standard criterion, i.e., an alpha (α) of 0.05 we see that 𝒑 > 𝟎. 𝟎𝟓, therefore,
because we have a greater p-value we would fail to reject or we would maintain the null
hypothesis (H0:) regarding the variances across the groups which signals that our assumption is
met (Field, 2013).
𝑭(𝒅𝒇𝟏 , 𝒅𝒇𝟐 = 𝒗𝒂𝒍𝒖𝒆, 𝒑 = 𝒑 − 𝒗𝒂𝒍𝒖𝒆)
Levene’s Test to identify whether population’s differences are equivalent (Field, 2018. p.
193-195).
MacCAT-T Dimensions (Group’s Knowledge) All Groups.
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Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
𝐹(2,147) = 1.098, 𝑝 = 0.336 (Significant difference in variance)
What we are testing is the null hypothesis that the population mean for the three groups are
all equal (Field, 2013). The alternative or the research hypothesis is that the population means
are unequal. Therefore, when we look at Table 3 the ANOVA summary, and our F-value, and pvalue we see a p-value that is less than 0.05. Therefore, with a statistically significant value that
is less than 𝟎. 𝟎𝟓, we would reject the null hypothesis (H0:) and infer there are significant
population mean differences in regarding the groups knowledge of MacCAT-T dimensions
(Field, 2013).
Table 4 is a summarizes the Robust Tests of Equality of Means, and shows the Welch and
Brown–Forsythe Fs, which is of no significance at this point due to the data already obtained
from the Levene’s test (Field, 2013). However, we will use the Robust Test of Equality of Means
can be used if needed as a reference guide to better understand the absolute differences within
each group if we use the group median (Field, 2013).
3) If your study includes more than three independent variables, run post hoc tests in SPSS®. Generate
an APA formatted table to depict your post hoc results and discuss your findings.
Table 5
Multiple Comparisons
Dependent Variable: dimensions
Tukey HSD
(I) Clinic
(J) Clinic
Maine
Behavioral
Clinic
Mercy Clinic
Mercy Clinic
Maine
Behavioral
Clinic
Spring Harbor
Clinic
Mean
Difference (IJ)
Std. Error
95% Confidence Interval
Sig.
Lower Bound Upper Bound
*
1.36881
.000
-14.5434
-8.0616
-2.30250
1.36881
.215
-5.5434
.9384
11.30250*
1.36881
.000
8.0616
14.5434
-11.30250
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Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
Spring Harbor
Clinic
Spring Harbor
Clinic
Maine
Behavioral
Clinic
Mercy Clinic
9.00000*
1.36881
.000
5.7591
12.2409
2.30250
1.36881
.215
-.9384
5.5434
-9.00000*
1.36881
.000
-12.2409
-5.7591
*. The mean difference is significant at the 0.05 level.
Table 6
dimensions
Tukey HSDa
Subset for alpha = 0.05
Clinic
Maine
Behavioral
Clinic
Spring Harbor
Clinic
Mercy Clinic
Sig.
N
1
2
50
37.7050
50
40.0075
50
.215
49.0075
1.000
Means for groups in homogeneous subsets are
displayed.
a. Uses Harmonic Mean Sample Size = 50.000.
Table 5 lists post-hoc test data (Tukey’s Test) and summary of Multiple Comparisons.
Because our assumption of Homogeneity of Variances appears to be met, I will interpret Tukey’s
Test instead of running and relying on other statistical tests at this point (Field, 2013). The posthoc test is a way of exploring possible mean differences, so without specific a priori hypotheses
in mind we will examine pairwise differences between the groups. For this dataset (MacCATT.sav) we have three groups and four dimensions transformed into one variable but nested. So,
we have Maine Behavioral Clinic, vs Mercy Clinic, vs Spring Harbor Clinic therefore, the mean
difference is computed by taking the mean from Clinic 1, subtracting the mean from Clinic 2, or
Clinic 3 etc. Looking at mean difference in Table 5 and the level of significance we can see that
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Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
we have a p-value (0.00) that indicates statistical significance. Therefore, we will interpret this
difference to mean that there are significant population differences between the three groups
(clinics) (Field, 2013).
Table 6 displays the means for groups in homogeneous subsets (MacCAT-T dimensions) and
shows the sample size 𝑵 = 𝟓𝟎 per each group, and the subset for alpha = to 0.05, the criterion pvalue which confirms the post-hoc assumption of Table 5 (Field, 2013).
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Problem of Practice Mock Study Development Template: Week Five
RES/720 Version 2
References
Field, A. (2013). Discovering Statistics Using IBM SPSS Statistics. Thousand Oaks, CA: SAGE.
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