UCP-Networks: A Directed Graphical Representation of Conditional Utilities

TL;DR

UCP-networks provide a new directed graphical model for utility functions that combines additive and conditional preference structures, enabling efficient decision-making and interactive utility elicitation.

Contribution

This paper introduces UCP-networks, a novel graphical representation of utility functions that integrates generalized additive models and CP-networks, improving computational efficiency and decision support.

Findings

Efficient computation of optimization and dominance queries.

Effective interactive elicitation procedure for utility refinement.

Demonstrated applicability in decision-making scenarios.

Abstract

We propose a new directed graphical representation of utility functions, called UCP-networks, that combines aspects of two existing graphical models: generalized additive models and CP-networks. The network decomposes a utility function into a number of additive factors, with the directionality of the arcs reflecting conditional dependence of preference statements - in the underlying (qualitative) preference ordering - under a {em ceteris paribus} (all else being equal) interpretation. This representation is arguably natural in many settings. Furthermore, the strong CP-semantics ensures that computation of optimization and dominance queries is very efficient. We also demonstrate the value of this representation in decision making. Finally, we describe an interactive elicitation procedure that takes advantage of the linear nature of the constraints on "`tradeoff weights" imposed by a UCP-network. This procedure allows the network to be refined until the regret of the decision with minimax regret (with respect to the incompletely specified utility function) falls below a specified threshold (e.g., the cost of further questioning.