When launched in QucsStudio 3.3.2, MonteCarlo example “filter” does not work properly. Components with value defined by equation (capacitors in this example) are not simulated in Monte Carlo analysis. Only components that are directly given tol() value (the inductor in this example) are included in MC analysis. Please disable (replace with short circuit) the inductor and see by yourself. I attach sch file. It comes from Example provided on qucstudio.de webpage.