1. A non-transitory computer-readable medium having instructions executable by a processor, the instructions comprising: a composite map generator programmed to: receive a plurality of data sets including values computed for each of a plurality of points for a given spatial region of tissue, each of the plurality of datasets characterizes electrical information for each of the plurality of points for a different time interval; combine the values computed for each of a plurality of points over at least two different time intervals; and normalize the combined values relative to a common scale; and an output generator programmed to generate a composite map for the given spatial region based on the combined values that are normalized.