Multiple viewpoints are often used in Requirements En-gineering to facilitate traceability to stakeholders, to struc-ture the requirements process, and to provide richer mod-elling by incorporating multiple conflicting descriptions. In the latter case, the need to reason with inconsistent models introduces considerable extra complexity. This paper de-scribes an empirical study of the utility of multiple world reasoning (using abduction) for domain modelling. In the study we used a range of different models (ranging from cor-rect to very incorrect), different fanouts, different amounts of data available from the domain, and different modelling primitives for representing time. In the experiments there was no significant change in the expressive power of mod-els that incorporate multiple conflicting viewpoints. Whilst this does not negate the advantages of viewpoints during requirements elicitation, it does suggest some limits to the utility of viewpoints during requirements modelling.
This paper is in Proceedings of 4th IEEE International Symposium on Requirements Engineering, Limerick,
Ireland, 7-11 June 1999.
It is also available over the Web: [pdf version]