High Quality Content by WIKIPEDIA articles! The constellation model is a probabilistic, generative model for category-level object recognition in computer vision. Like other part-based models, the constellation model attempts to represent an object class by a set of N parts under mutual geometric constraints. Because it considers the geometric relationship between different parts, the Constellation Model differs significantly from appearance-only, or "Bag_of_words_model" representation models, which explicitly disregard the location of image features.