“…Similar observations have been seen in the optimal product selection in software product line [16], [45], [52], [66], [77], [113], [119], [120], [132] where the correctness of configurations is regarded as one objective and equally rated as other objectives (e.g., richness of features and cost). This may lead to an invalid product to be evaluated better than a valid product if the former performs better in other objectives, which is apparently of no value to the DM.…”