In the framework of models generated by compositional expressions, we solve two topical marginalization problems (namely, the \emph{single-marginal problem} and the \emph{marginal-representation problem}) that were solved only for the special class of the so-called ``canonical expressions". We also show that the two problems can be solved ``from scratch" with preliminary symbolic computation.
marginalization, compositional expression, compositional model, syntax tree
05C65, 05C85, 65C50, 60E99, 68T37