Techniques are described for generating a statistical model from observed click chains. The model can be used to compute a probability that a document is relevant to a given search query. With the model, a probability of a user examining a given document in a given search result conditionally depends on: a probability that a preceding document in the given search result is examined by a user viewing the given search result; a probability that the preceding document is clicked on by a user viewing the given search result, which conditionally depends directly on the probability that the preceding document is examined and on a probability of relevance of the preceding document.