A framework for supporting discourse in the design decision-making process

Decision-making involves complex negotiations and discourse among stakeholders. The opinions of these stakeholders are expressed in terms of various levels of uncertainty due to the imperfection of available information. These uncertain assessments should be handled in a formalism which can help reasoning about the dependability of decisions and build consensus among stakeholders. An adaptation of Soft Systems Methodology has been applied in an attempt to improve decision-making, especially in engineering design processes. A processbased approach has been used for gaining and maintaining a systemic view of the activities. The enactment of each process may require one or more issues to be addressed, which could be the subject of debate and discussion. That discourse is represented in an Issue-Based Information System (IBIS) model. The uncertain positions taken by the participants are combined using the generalized natural combination rule which has been derived from a generic method of aggregation of uncertain evidence developed for evidential reasoning. This enables the decision-maker to assess the strength of arguments with respect to objectives/criteria. The system enhances decision-making by enabling an efficient mechanism for reasoning with uncertain premises. Communicating design intents between stakeholders is another advantage of this system.