この節の作者: Rebecca Vederhus, Sebastian Jentschke
From SPSS to jamovi: Analysis of Covariance (ANCOVA)¶
This comparison shows how to test the assumption of homogeneity of regression slopes in SPSS and jamovi. The SPSS test follows the description in chapter 13.7 in Field (2017), especially figure 13.9 and output 13.12. It uses the data set Puppy Love Dummy.sav which can be downloaded from the web page accompanying the book.
SPSS | jamovi |
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In SPSS, you can run this test using: Analyze → General Linear Model
→ Univariate . |
In jamovi you do this using: Analyses → ANOVA → ANCOVA . |
In SPSS, move Happiness to the Dependent Variable box, Dose to
the Fixed Factor(s) box, and Puppy_love to the Covariate(s) box. |
In jamovi, move the Happiness variable to Dependent Variable , the
Dose variable to Fixed Factors , and the Puppy_love variable to
Covariates . |
Access the Model window, and click Build terms . Then, mark the
variables Dose and Puppy_love , open the drop-down menu and choose
Interaction . |
Next, open the Model window. Mark both Dose and Puppy_love , then
click the arrow with the drop-down menu and click Interaction . |
Comparisons between the output in SPSS and jamovi shows that the results are the same. | |
In SPSS, the Tests of Between-Subjects Effects table shows the sum of
squares for the variables, as well as the interaction term (Dose *
Puppy_love). The tables also includes degrees of freedom, mean square,
F-values and significance values. |
In jamovi, these results are found in a similar ANCOVA table, which also
includes sum of squares, degrees of freedom, mean square, F-values and
significance values. These values are located in the same order as in the
SPSS table. |
The main difference between the results in SPSS and jamovi is that SPSS provides values for the following: If one compares the numerical values, they are the same: SS*<sub>Dose</sub> = 36.6, *p < .01; SS*<sub>Puppy_love</sub> = 17.2, *p < .05; SS*<sub>Dose * Puppy_love</sub> = 20.4, *p < .05. |
|
If you wish to replicate those analyses using syntax, you can use the commands below (in jamovi, just copy to code below to Rj). Alternatively, you can download the SPSS output files and the jamovi files with the analyses from below the syntax. | |
UNIANOVA Happiness BY Dose WITH Puppy_love
/METHOD=SSTYPE(3)
/INTERCEPT=INCLUDE
/CRITERIA=ALPHA(0.05)
/DESIGN=Dose\*Puppy_love Dose Puppy_love.
|
jmv::ancova(
formula = Happiness ~ Dose + Puppy_love + Dose:Puppy_love,
data = data)
|
SPSS output file containing the analyses | jamovi file containing the analyses |
References
Field, A. (2017). Discovering statistics using IBM SPSS statistics (5th ed.). SAGE Publications. https://edge.sagepub.com/field5e