I am trying to replicate the confidence interval calculation that Mplus produces with the CINTERVAL statement so that I can calculate others by hand using the variance covariance matrix when including X and X^2 terms in the model.
Can you please explain how the 95% CI is calculated for the parameter estimates?
I tried B +- 1.96*se, but the CI is slightly off. Am I missing something?
I am running an analysis with all continuous variables. I am running the model with a stratification, cluster and weight variable, but this should only effect the SE, not the calculation for the CI, correct?