Can I include an explanatory variable that stratified the population in model?
I have 400 randomly selected urban households. I have 400 rural households selected from 15 villages census style. Food insecurity (dichotomous) is my outcome variable. I want to find determinants of household food insecurity. I know urban/rural is likely a factor.
Can I create ONE regression model with urban/rural as one of several explanatory variables or do I need TWO separate models? I believe the argument for one model is that sampling methods are not as important for identifying potential determinants and putting the samples together increases my sample size. I have chosen to use TWO models but am not 100% confident on the rationale. I believe that it is not appropriate to enter explanatory variables that were used in defining sample selection (the sample was stratified on urban/rural). But I do not know why one cannot enter a variable on which the sample was stratified. Can anyone help explain?
Thank you!
I have 400 randomly selected urban households. I have 400 rural households selected from 15 villages census style. Food insecurity (dichotomous) is my outcome variable. I want to find determinants of household food insecurity. I know urban/rural is likely a factor.
Can I create ONE regression model with urban/rural as one of several explanatory variables or do I need TWO separate models? I believe the argument for one model is that sampling methods are not as important for identifying potential determinants and putting the samples together increases my sample size. I have chosen to use TWO models but am not 100% confident on the rationale. I believe that it is not appropriate to enter explanatory variables that were used in defining sample selection (the sample was stratified on urban/rural). But I do not know why one cannot enter a variable on which the sample was stratified. Can anyone help explain?
Thank you!
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