Notes on separable preferences
Examples are constructed to show that Gorman's important basic theorem for overlapping strictly separable sectors does not hold if the sectors are only nonstrictly separable. This is done with the help of a new definition for the notion of nonstrict separability of utility preferences. The new definition is equivalent to that of Bliss, but it clarifies the relationship between the geometry and representation of preferences with separable sectors. The geometric insight gained leads to the conjecture that if all sectors are strictly essential, then Gorman's basic theorem would hold.
scientific article; zbMATH DE number 3945820