Hello, i want to estimate the causal impact on a scale variable, using the difference-in-difference-method and the following 4 groups - control- and treatment group (counterfactual analysis) - two periods, measurement before and after treatment. After discovering and estimating the causal effect (of course, only if existing) i like to make deeper analysis, causal mediation analysis, and fixed effects analyisis. Does anyone know a package or packages, with which one can do this estimations, calculation and graphics? Thanks a lot for any information. iksmax [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.