Effects of Structural Complexity and Team Task Strategy on Object-Oriented Software Maintenance: An Experimental Test

This study develops and empirically tests the idea that the impact of structural complexity on perfective maintenance of object-oriented software is significantly determined by the task strategy of programming teams (independent or collaborative). Two key dimensions of software structure, coupling and cohesion, were analyzed with respect to both the maintenance effort and the perceived ease-of-use by pairs of programmers. Hypotheses based on the distributed cognition and task interdependence theoretical frameworks were tested using data collected from a controlled lab experiment employing professional programmers. The results show a significant interaction effect between coupling, cohesion, and task strategy on both maintenance effort and perceived ease-of-use. Maintenance of the highly cohesive programs required 47% lower effort than the low cohesive programs, and was 80% lower for programs with low coupling than for the highly coupled programs. Further, our results would predict that managers who allocate maintenance tasks to independent or collaborative programming teams depending on the structural complexity of software could lower their team's maintenance effort by as much as 70% over managers who use simple uniform resource allocation policies. These results highlight the importance of achieving congruence between task strategies employed by collaborating team members and the structural complexity of software. (199 words)