1. A computer-implemented method for wide area surveillance of a geographic region comprising: identifying by one or more computer processors a search space associated with a geographic region having a plurality of sub-regions; dividing by the one or more computer processors the search space into a plurality of search cells; collecting by the one or more computer processors observation data for each of the plurality of search cells based on a scan of the geographic region; calculating by the one or more computer processors an event generation rate for each of the search cells based on the collected observation data; identifying by the one or more computer processors one or more of the sub-regions as one or more regions of interest based on the calculated event generation rates; estimating by the one or more computer processors a coverage pattern for each of the one or more regions of interest; calculating by the one or more computer processors a desired revisit rate for each of the one or more regions of interest based on the estimated coverage pattern; and outputting by the one or more computer processors the desired revisit rate for scanning the corresponding region of interest.