1. A method for refining a process model, comprising: mining a process model from a set of execution traces; determining whether the process model is too dense or too sparse; learning a predictive model from the execution traces to predict an outcome; modifying the predictive model with a processor, comprising: making the predictive model more specific if it is determined that the process model is too dense; and making the predictive model more general if it is determined that the process model is too sparse; and mining a refined process model from updated traces based on attributes present in the modified predictive model.