which statement best defines the purpose of a t-error regression? which of the following models is not used for robustness purposes? why is the t-errors function not useful in regression why is the t-error used why is the gaussian model useful what is the difference between the gaussian and multivariate regression models what is t error mean in a standard regression why is the multivariate t model useful why are student t errors useful? what model is used for heavy tail analysis which gaussian model is the most useful? why does a regression have student error why is the multivariate t model useful which of the following is the most common method for performing a regression? why was t errors useful for gaussian regressions why do t error regressions is multivariate t regression valid is the t model useful in regression why is multivariate t model useful why is the t error in regression useful