1. A computer-implemented method for automatically selecting one or more advertisements to include in a web page, comprising: conducting one or more experiments using a computer simulation simulating a specified future time period; wherein each of the one or more experiments involves: hypothetically presenting at least one advertisement, from a plurality of available advertisements, in the web page, and predicting, based, at least in part, on historical data, user interaction of a hypothetical user with the at least one advertisement; based on the predicted user interaction, automatically selecting the one or more advertisements to present in the web page; and in response to selecting the one or more advertisements to present in the web page, presenting the one or more advertisements in the web page; wherein the method is performed by one or more computing devices.