An integrated group decision-making approach to quality function deployment

Quality Function Deployment (QFD) is a multi-disciplinary team process in which team member preferences are often in conflict with respect to varied individual objectives. Successful applications of QFD, thus, rely on: (1) effective communication among team members to reach a consensus; (2) assigning importance levels that reflect each individual member's preferences; and (3) mutual interaction of these two factors. No previous paper in the QFD literature has attempted to aggregate team members' opinions in the case where each individual has his or her own criteria. In this study, we consider both agreed criteria, if any, and individual criteria, simultaneously; whereas AHP, MAUT, and others are based only on an agreed set of criteria. Specifically, we modify the nominal group technique to obtain customer requirements, and integrate agreed and individual criteria methods to assign customer's importance levels in general situations where some members in a team have an agreed criteria set while others prefer individual criteria sets. By using voting and linear programming techniques, the proposed approaches consolidate individual preferences into a group consensus in situations starting with or without (partial) agreed criteria sets. This integrated group decision-making system minimizes inconsistency over group and individual preferences and provides preference ordering for alternatives through iterative communication and the resolution of any inconsistencies that exist between the group and individuals, and amongst the individuals themselves.