A Hybrid Set of Complexity Metrics for Large-scale Object-oriented

systems have recently been found to share global network characteristics such as small world and scale free, which go beyond the scope of traditional soft-ware measurement and assessment methodologies. To measure the complexity at various levels of granu-larity, namely graph, class (and object) and source code, we proposed a hierarchical metrics set in terms of coupling and cohesion—the most important characteristics of software, and analyzed a sample of 13 open-source OO software systems to empirically validate the set. Experimental results of the correlations between cross-level metrics indicated that the graph measures of our set complement traditional software metrics well from the viewpoint of network thinking, and would provide more effective information about fault-prone classes in practice