Define the opposite of one of the two scalar functions that are maximized when running the E-M algorithm for CUBE models with covariates for feeling, uncertainty and overdispersion.
Qdue(param, esterno2, q, m)Vector of initial estimates of parameters for the feeling component and the overdispersion effect
Matrix binding together the column vector of the posterior probabilities that each observed rating has been generated by the distribution of the first component of the mixture, the column vector of ordinal responses, and the matrices W and Z of the selected covariates for feeling and overdispersion, respectively
Number of selected covariates for explaining the feeling component
Number of ordinal categories
It is iteratively called as an argument of "optim" within CUBE function (with covariates) as the function to minimize to compute the maximum likelihood estimates for the feeling and the overdispersion components.