Refined metric for a-posteriori novelty assessments

The concept of novelty in terms of 'uncommonness' of ideas is one of the most considered in design studies. Accordingly, the metric developed by Shah, Vargas-Hernandez and Smith in 2003 (SNM) is still one of the most largely used. Nonetheless, it presents non-negligible and still unsolved problems when applied to realistic sets of ideas implementing heterogeneous numbers of attributes. This paper aims at identifying the roots of these problems and at proposing a refined assessment approach, capable to extend the applicability of SNM to any set of ideas. Generic boundary cases have been used to demonstrate the validity of the proposal, while its potential impact on the final novelty values has been estimated by assessing a real set of 100 ideas.