Results are presented of an analysis of several defect models using data collected from two large commercial projects. Traditional models typically use either program matrices (i.e. measurements from software products) or testing time or combinations of these as independent variables. The limitations of such models have been well-documented. The models considered use the number of defects detected in the earlier phases of the development process as the independent variable. This number can be used to predict the number of defects to be detected later, even in modified software products. A strong correlation between the number of earlier defects and that of later ones was found. Using this relationship, a mathematical model was derived which may be used to estimate the number of defects remaining in software. This defect model may also be used to guide software developers in evaluating the effectiveness of the software development and testing processes.>

The theory of software science was developed by the late M. H. Halstead of Purdue University during the early 1970's. It was first presented in unified form in the monograph Elements of Software Science published by Elsevier North-Holland in 1977. Since it claimed to apply scientific methods to the very complex and important problem of software production, and since experimental evidence supplied by Halstead and others seemed to support the theory, it drew widespread attention from the computer science community.

A Management Information System (MIS) performs transactional processing and sup plies information to organizational manage ment for planning and decision making. It is suggested that the MIS administrator should be concerned with the system's cost effectiveness, completeness, and degree of use. The amount of training of MIS users and the necessity for a dynamic system are discussed. When implementing a new MIS, the administrator should concentrate on using good organizational politics, should avoid computer jargon, and should encourage organizational personnel involvement in planning. The MIS should be built on existing data processing structures, and the MIS administrator should be very care ful about data accessibility and security.