1. A method comprising, by one or more computing devices: receiving, from one or more sensors, biomechanical data of a first user performing a plurality of actions of a first action-type and outcome data of a plurality of outcomes corresponding to the respective plurality of actions; determining, based on the received biomechanical data, a plurality of sets of action-parameter values corresponding to the respective plurality of actions; and generating an athletic-performance model of the first user based on the plurality of sets of action-parameter values, wherein the athletic-performance model is a statistical model comprising probabilities computed with respect to the sets of action-parameter values and the outcome data.