  In this paper, we consider classes of decision tables with many-valued
decisions closed under operations of removal of columns, changing of decisions,
permutation of columns, and duplication of columns. We study relationships
among three parameters of these tables: the complexity of a decision table (if
we consider the depth of decision trees, then the complexity of a decision
table is the number of columns in it), the minimum complexity of a
deterministic decision tree, and the minimum complexity of a nondeterministic
decision tree. We consider rough classification of functions characterizing
relationships and enumerate all possible seven types of the relationships.
