clustered data

I am currently conducting mediation analyses using the mediation package in R. I usually use SAS but this approach seemed more straightforward. I am using a Poisson model (link= log). The mediation runs fine, the issue is that participants in my study contributed more than one sample (for the...

I'm unsure how to interpret the output of a fixed effects (in the econometric sense) logistic regression model using cross-sectional data. I'm struggling with the 'cluster-specific' interpretation these models have. I sort of understand how this works with panel data, but I'm not sure whether...

How to insert an already-clustered data set in SPSS? I have a data set where there are repeated laboratory measurements for each patient, that is the patient is the cluster. How to inform SPSS that the patient ID variable is the "clustering" variable? Or is that not possible in SPSS ?