This document discusses probabilistic relational models for link prediction. It introduces probabilistic relational networks, including relational Bayesian networks (RBNs) and relational Markov networks (RMNs). RBNs define a joint probability distribution over attributes and relations. RMNs focus on symmetric interactions using clique templates. Both approaches can be used for link prediction by modeling factors that affect relations between entities, such as attributes, structural properties, and complex patterns.