1. A system comprising: one or more computing devices; and a computer-readable medium coupled to the one or more computing devices having instructions stored thereon which, when executed by the one or more computing devices, cause the one or more computing devices to perform operations comprising: receiving a baseline resource and one or more candidate change resources, the baseline resource and the one or more candidate resources being displayable on a display; rendering the baseline resource as an image to provide an image file including corresponding image data; rendering the one or more candidate change resources as respective images to provide one or more image files each including corresponding image data; generating, for each image of the images, a salience map based on the image; generating, for each resource of the resources, a simulated eye trace based on the salience map corresponding to the resource, the generating including, for each salience map: determining a starting fixation point, determining a subsequent fixation point based on statistical distribution data, and generating a respective simulated eye trace defined between the starting fixation point and the subsequent fixation point; and generating additional maps based on the simulated eye traces to determine one or more statistics of interest, the one or more statistics of interest reflecting a user behavior in interacting with a resource.