What are the minimum numbers of cross sectional units in Long Panel Datat Analysis, as it is difficult to collect data from too many companies in developing contries?.
Also, what is the model uesed, in this case? Thank you
There are many types of longitudinal statistical models, including autoregressive/crosslagged models, change score models, growth curve models, and latent state-trait models. The type of model to use depends on your research questions, the nature of the variables, and what you want to find out.
Likewise, the required sample size depends on many factors (e.g., the type of statistical model, the number of variables, the number of time points, effect sizes). It is therefore difficult if not impossible to give general recommendations. I tend to think that the best way to make an informed guess about the necessary sample size is by running a simulation that should ideally be as realistic as possible in terms of the expected parameter estimates. This also allows you to study which aspects of the variables and model are most sensitive to a small sample.