A direct relationship extraction unit generates a direct relationship list indicating a set of a direct dependence source, a direct dependence destination, and a direct dependence type. A storage unit stores an indirect relationship rule including a plurality of direct dependence types, an element relationship, a dependence source element, and a dependence destination element. An indirect relationship extraction unit extracts, from a direct relationship list, a plurality of pieces of direct relationship information corresponding to the plurality of direct dependence types and the element relationship included in the indirect relationship rule, extracts an indirect dependence source which is an element corresponding to a dependence source element in the indirect relationship rule from the extracted plurality of pieces of direct relationship information, and extracts an indirect dependence destination corresponding to a dependence destination element in the indirect relationship rule from the extracted plurality of pieces of direct relationship information.