Greetings! I have a syntax file that I run to generate a Spearman partial correlation.
NONPAR CORR covar1 covar2 var1 var2 var3
/MISSING = LISTWISE
/MATRIX OUT(*) .
RECODE rowtype_('RHO'='CORR') .
PARTIAL CORR var1 var2 var3 BY covar1 covar2
/SIGNIFICANCE = TWOTAIL
/MISSING = LISTWISE
/MATRIX IN(*) .
(full credit to Steven Bradburn: How To Perform A Non-Parametric Partial Correlation In SPSS)
After pasting the output into Excel, it looks something like this (minus var3 for simplicity, values made up):
Correlations |
Control Variables |
var1 |
var2 |
var3 |
covar1 covar2 covar3 |
var1 |
Correlation |
1.000 |
0.2 |
0.3 |
Significance (2-tailed) |
|
.01 |
0.05 |
df |
0 |
0 |
1 |
var2 |
Correlation |
0.2 |
1.000 |
-0.4 |
Significance (2-tailed) |
.01 |
|
0.02 |
df |
1 |
0 |
1 |
This normally works very well and only requires minor cleanup for self-comparisons. However, I've run into an issue where adding another covariable (covar4) with no other changes results in an output like this:
Correlations |
Control Variables |
var1 |
var2 |
var3 |
covar1 covar2 covar3 covar4 |
var1 |
Correlation |
1.000 |
|
|
Significance (2-tailed) |
|
|
|
df |
0 |
0 |
0 |
var2 |
Correlation |
|
1.000 |
|
Significance (2-tailed) |
|
|
|
df |
0 |
0 |
0 |
I am stuck trying to figure out why this is happening. If it helps, all variables involved are numeric. Covar1 and 4 are scales, while covar2 and 3 are nominal.
Any help figuring this out would be greatly appreciated.
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Andrew Pucka
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