Constrained preference elicitation

A planner wants to elicit information about an agent's preference relation, but not the entire ordering. Specifically, preferences are grouped into “types,” and only type. We first assume that beliefs randomization subjective, show a space of types is elicitable if each type defined by what agent would choose from some list menus. If objective, then additional spaces can be elicited, though convexity condition must satisfied. These results remain unchanged when we consider setting with multiple agents.