https://ir.unisa.ac.za/handle/10500/23885 2026-06-19T21:55:18Z https://ir.unisa.ac.za/handle/10500/24405 Some current practices in evaluating IT benefits in South African organisations Sutherland, F IT has a dynamic impact on organisations and little research has been done especially on the extent to which senior executives take the different system types into account when they appraise an IT investment. The aim of this paper is to identify current IT investment evaluation practices using the framework of system portfolios identified by McFarlan. Twenty four respondents were drawn from business organisations. Wherever possible, Chief Information Officers (CIOs) and Senior Business Executives (SBEs) were interviewed from the same organisation. Content analysis was used to identify fourteen major concepts from the interview transcripts. The results of this study indicate that payback continues to be the most popular technique/or appraising IT investments. CIOs tend to adopt rigorous cost benefit analyst techniques regardless of system type, whilst SBEs take cognisance of the system type and are comfortable with the informality of intangible benefits arising from strategic systems. Neither group regularly conducted post-implementation audits. The SBEs felt that customer response was a sufficient ex-post measure of the benefits from IT, CIOs gave lack of time as their commonest reason for omitting post-implementation auditing and felt that formalised post-implementation auditing would enhance the image of IT within the organisation. 1994-01-01T00:00:00Z https://ir.unisa.ac.za/handle/10500/24154 Specialization by exclusion Theron, H; Cloete, I This paper presents a theoretical analysis of the search schemes employed by AQ, CN2 and the recently introduced BEXA algorithm. These covering algorithms induce disjunctive concept descriptions, and employ a general-to-specific search when constructing the conjunctions in these expressions. BEXA specializes a conjunction by excluding values from it, while CN2 and AQ specialize a conjunction by appending atoms to it. It is shown that the latter two algorithms' search process can also be viewed as one of excluding values. This makes it possible to show that the three algorithms' search schemes differ only with respect to the number of values excluded at each specialization step, and the number of different specializations that are constructed. We show that the search for accurate and simple conjunctions can be restricted to find elements of the set CM of most general and consistent conjunctions. CM is characterized precisely. BEXA exploits this characterization to induce simple and accurate concept descriptions efficiently. 1994-01-01T00:00:00Z https://ir.unisa.ac.za/handle/10500/24153 The innovative management of information in the mid-1990s Remenyi, D This paper reviews recent literature on the subject of the operational and financial difficulties facing business and manage­ment in the mid 1990's. It identifies how, due to generally poor results, business is under more pressure to perform than ever before. The paper proceeds to indicate how currently accepted business paradigms are no longer working as well as they used to and how, in order.to return to appropriate levels of profitability, new paradigms for corporate structure and individual motivation are needed which emphasise renewal and innovation. This theoretical review of the literature finds that business process reengineering is an important way forward towards innovation which also allows organisations to cope with increasingly difficult business conditions. From a research point of view the paper goes on to suggest a theoretical conjecture concerning the creation of business or management paradigms which might be helpful in improving business performance in the twenty first century. 1994-01-01T00:00:00Z https://ir.unisa.ac.za/handle/10500/24152 A linear time algorithm for the longest (s-t)-path problem restricted to partial k-trees Mata-Montero, M; Ellis, JA The Longest (s-t)-path Problem, a known NP-complete set, is shown to admit a linear time solution when the instances of the problem are restricted to partial k-trees. This class of graphs is defined and some of the properties of partial k-trees, those needed for our algorithm are proved. 1994-01-01T00:00:00Z