Ambiguity 1 Artificial intelligence 1 Bayesian networks 1 Click-through rate 1 Consumer behavior 1 Hierarchical Bayesian model 1 Hierarchical Bayesian modeling Hierarchical bayesian 1 Learning systems 1 Machine learning 1 Multiple products 1 Probabilistic topic models 1 Search engines 1 Semantics 1 Sponsored search advertising 1 Sponsored searches 1 Statistics 1 Topic model 1 Topic models 1