摘要:

Many software measures have been forwarded on the simple basis of a high linear correlation coefficient with some measurable quantities. The linear correlation coefficient is an unreliable statistic for deciding whether an observed correlation indicates significant association. Several published software measure experiments collected more than 20 different measurements, or have 14 or fewer observations. With considerable data from small samples, the probability of ‘discovering’ a ‘significant’ correlation is high. We present a computer simulation experiment where the correlation between sets of randomly generated numbers is calculated. We also look at randomly generated numbers in the ranges that would be expected in Halstead's Software Science [1] measures. Our results show that the average maximum linear correlation for randomly generated numbers is 0.70 or higher if the sample size is low compared to the number of variables. Alternative statistical approaches to obtaining meaningful significant results are presented.

DOI:10.1049/sej.1993.0002

出版商:IEE    

年代:1993

数据来源: IET

摘要:

The task structure diagramming technique can be used to graphically denote process specifications. In task structure diagrams, sequential execution, iteration, choice and parallelism can be expressed. In this paper, task structure diagrams are extended with a synchronisation mechanism and a formal semantics is given by means of a translation to process algebra. By using known techniques for proving equivalence of process specifications in process algebra, the translation provides a basis for proving equivalence of task structures.

DOI:10.1049/sej.1993.0003

出版商:IEE    

年代:1993

数据来源: IET

摘要:

Criteria for test data adequacy are rules for deciding when enough testing has been performed. Development of these criteria is an important objective of research in software testing. In this paper, the abstract properties of adequacy criteria are investigated in a formal axiomatic style. Starting from work by Weyuker [1, 2] and Parrish and Zweben [3], we define an adequacy criterion as a function from specifications, programs and subsets of data to a degree of the adequacy of the test set. In this paper, we address the general properties of adequacy criteria, independent of the syntax and semantics of specifications and programs. In subsequent work, we will address properties related to specifications and programs. The dependencies between the axioms, as well as the relationship between them and those in Weyuker's and Parrish and Zweben's system, are also investigated.

DOI:10.1049/sej.1993.0004

出版商:IEE    

年代:1993

数据来源: IET

摘要:

Hardware and software engineers are called upon to collaborate in building complex high-quality computer-based systems. This paper seeks to facilitate this collaboration by laying foundations for a ‘common engineering culture’; a coherent, powerful structure of ideas central to system designers and procurers, with particular relevance to IT systems, hardware and software. We define and formalise the notions of ‘system’ and ‘model’, and explore the nature of models of systems in terms of their (quantitatively or qualitatively) measurable properties. We show how the property models of system components combine in the structural model of the system to form the property model of the system as a whole. We also offer illustrative examples from hardware and software to explain the use of models in system specification and design.

DOI:10.1049/sej.1993.0005

出版商:IEE    

年代:1993

数据来源: IET

摘要:

In this paper we describe an abstract model for the development of object-oriented software in a context where several programmers work together as a team. We introduce the different levels that compose our model, mapping its concepts and tools to existing systems whenever possible. The goal of this work is to design an environment for co-operative programming that deals specifically with the needs of developers using object-oriented technology. Our model is based on existing software engineering tools for the development of medium and large software projects, and also on a survey of user requirements for object-oriented programming. We explain the reasons why existing software engineering tools for team programming are not suited to object-oriented technology. We also briefly describe our prototype and the tools necessary to support our co-operative object-oriented programming model.

DOI:10.1049/sej.1993.0007

出版商:IEE    

年代:1993

数据来源: IET