A model generating device acquires event information including a time when execution of an event is started, a time when execution of the event is finished, and the type of the event. The model generating device assumes model candidates each showing a relationship between an event and another event triggered by the former event on the basis of the acquired event information, and makes a combination of the assumed model candidates. The model generating device searches the assumed model candidates to find a candidate that matches an existing model. The model generating device withdraws the model candidate searched for from the combination of the model candidates, and withdraws a candidate that is to be withdrawn from the combination of the model candidates in association with withdrawal of the model candidate found as a result of the search, thereby updating the combination of the model candidates. The model generating device thereafter generates a new model on the basis of the updated combination of the model candidates.