The cognitive activities performed by systems designers during systems development include problem understanding, problem decomposition and solution speci"cation. One aspect of object-oriented (OO) approaches to system design that appeals to many adopting organizations is the purported naturalness, i.e. the consistency of OO approaches with these cognitive activities of problem solving. Essentially, OO aims to abstract components of the problem of system development to a high level that parallels problem solving in the world the system represents. In other words, knowing how a problem is solved in the real world informs one about how the OO system solves the problem. Thus, the OO development process and the resulting OO model are believed to be consistent with innate cognitive activities and consistent with the problem/real world, respectively. A cognitive mapping method was used to ask graduate students experienced with OO techniques about their perceptions of what is complex (di$cult to understand) about OO systems. Their responses include a set of concepts, categories of similar concepts and cognitive maps that reveal what they believe is di$cult about using OO techniques. Evaluating these perceptions in terms of the cognitive activities of system design reveals problem decomposition was perceived as the activity that caused the most di$culties related to learning OO techniques. Problem understanding was the goal of the participants, while the solution activity ranked lower in importance but contained many issues essential to systems development and in#uenced problem understanding.
2001 Academic Press