Design methodology for concurrent software systems employing modelling and simulation
William E. Riddle · ACM SIGSIM Simulation Digest · 1977
There is no single attribute or characteristic which distinguishes a software system as complex - rather, software system complexity may be assessed only in terms of a complicated combination of a variety of quantitative and qualitative measurements. Typical quantitative measures are size, number of components and length of the construction period - generally these can be artificially increased by inexperienced or inept designers or programmers. Measures of a more qualitative nature are ones such as under-standability and modifiability - these are generally dependent upon the experience and ability of those trying to measure the system's complexity.