Dear forum,
I am currently working on my thesis. A central part is a regression model with the following variables:
Dependent variable: support for nuclear energy (continuous/scale variable)
Independent variables:
- Positive (dummy variable which is equal to 1 if respondent has received a positive frame of nuclear energy in his survey);
- Negative (dummy variable which is equal to 1 if respondent has received a negative frame of nuclear energy in his survey);
- Dual (dummy variable which is equal to 1 if respondent has received both a positive and a negative frame of nuclear energy in his survey);
- Positive * level of value endorsement (the level of value endorsement is a continuous variable);
- Negative * level of value endorsement;
- Female (1 if respondent is female);
- Self-placement on political left-right scale (continuous variable).
The problem is that I have detected heteroscedasticity in my regression model. The ZRESID - ZPRED plot has the characteristic cone shape which indicates heteroscedasticity. I want to fix this by using heteroscedasticity robust standard errors.
How do I get SPSS to calculate these for me? I am unfamiliar with the GLM setting of SPSS, and when I do try to use the GLM, I still can't find the option to calculate parameters with robust standard errors. Please help me! Many thanks.
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Marnix van Thiel
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