Representing Composites in Conceptual Modeling
Using an object or entity class to represent a composite provides straightforward answers, making this approach superior to the use of relationship classes or associations.
Ron Weber
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-sing Ontology to Validate Conceptual Models
Theories of ontology lead to improved conceptual models and help ensure they are indeed faithful representations of their focal domains.
Computer technology and jobs: an impact assessment model
A model is proposed that associates the impact of computer technology on a job, with the set of underlying characteristics that describe the activities performed on the job. An empirical test of the model has been undertaken. One thousand and thirty-five experts assessed the impact of computer technology that they believed would occur on 306 jobs over a three-year period. Job characteristics data was obtained from prior analyses of the jobs, using the Position Analysis Questionnaire (PAQ). Six job dimensions derived from analysis PAQ data were significant predictors of the technological impact ratings provided by the experts: engaging in physical activities; being aware of the work environment; performing clerical-related functions; working in an unpleasant or hazardous environment; performing service-related activities; and performing supervising, directing, and estimating functions.
Structured tools and conditional logic: an empirical investigation
Prior research has identified two psychological processes that appear to be used by programmers when they perform design and coding tasks: (a) taxonomizing—identifying the conditions that evoke particular actions; and (b) sequencing—converting the taxa into a linear sequence of program code. Three structured tools—structured English, decision tables, and decision trees—were investigated in a laboratory experiment to determine how they facilitated these two processes. When taxonomizing had to be undertaken, structured English outperformed decision tables, and decision trees outperformed structured English. When sequencing had to be undertaken, decision trees and structured English outperformed decision tables, but decision trees and structured English evoked the same level of performance.
The economics of designing generalized software
The choice of the attributes to be incorporated in a generalized software package is a complex design task, much like the choice of the characteristics of the basic model and the options to be offered when a new automobile is being designed. Some empirical evidence available suggests that the choices made by generalized software designers are not always well founded; for example, some functions included in the software are hardly, if ever, used, while functions that would be used extensively are not available. To assist the designer, we formulate a market model showing the interactions between the producers (designers) of generalized software and the consumers (users) of generalized software. The model provides insight into those factors that affect the demand for a package and the variables to be considered in a profit-maximizing decision.
Some factors affecting program repair maintenance: an empirical study
An empirical study of 447 operational commercial and clerical Cobol programs in one Australian organization and two U.S. organizations was carried out to determine whether program complexity, programming style, programmer quality, and the number of times a program was released affected program repair maintenance. In the Australian organization only program complexity and programming style were statistically significant. In the two U.S. organizations only the number of times a program was released was statistically significant. For all organizations repair maintenance constituted a minor problem: over 90 percent of the programs studied had undergone less than three repair maintenance activities during their lifetime.
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