1. A method, comprising: obtaining a global version of a statistical model and a user-specific version of the statistical model for a user; applying, by one or more computer systems, the global version to member features of the user and job features of a set of jobs to generate a first ranking of the jobs for the user; applying, by the one or more computer systems, the user-specific version to the member features and the job features for a highest-ranked subset of jobs in the first ranking to generate a second ranking of the jobs for the user; and outputting, to the user, at least a portion of the second ranking as a set of job recommendations; wherein applying the global version to the member features and the job features to generate the first ranking of the jobs for the user comprises: using a job feature key in an inverted index to retrieve the job features for a subset of the jobs that matches the job feature key; and applying the global version to the member features and the retrieved job features to calculate a global score for each job in the subset of jobs.