An event matrix may comprise labels and indicators corresponding to objects and links of an ontology. The objects and links may be determined from a plurality of data sources by a data integration system. Some of the labels may correspond to event objects, and may be arranged in a first spatial dimension at least in part on the basis of dates associated with said event objects. Other labels may correspond to non-event objects, and may be arranged in a second spatial dimension. Indicators may correspond to links between the event and non-event objects. An indicator for a particular link may be positioned with respect to the first and second spatial dimensions in accordance with the locations of the labels that correspond to the objects connected by the link.