Evaluate the expectation and variance of a law.
Use the function by typing:
moments\(j\)(x,par1,par2,\(etc.\))
where \(j\) is the index of the law and par1, par2, \(etc.\) are the
parameters of law \(j\).
Pierre Lafaye de Micheaux, Viet Anh Tran (2016). PoweR: A Reproducible Research Tool to Ease Monte Carlo Power Simulation Studies for Studies for Goodness-of-fit Tests in R. Journal of Statistical Software, 69(3), 1--42. doi:10.18637/jss.v069.i03