Preferences in Constraint Satisfaction and Optimization

We review constraint-based ap - proaches to handle preferences. We start by defining the main notions of constraint programming and then give various concepts of soft constraints and show how they can be used to model quantitative preferences. We then consider how soft constraints can be adapted to handle other forms of preferences, such as bipolar, qualitative, and temporal preferences. Finally, we describe how AI techniques such as abstraction, explanation generation, machine learning, and preference elicitation can be useful in modeling and solving soft constraints. Intuitively, constraints are restrictions on the possible scenarios.