Preferences stability: A measure of preferences changes over time

Traditionally, preferences have been considered stable although there are growing evidences that such stability is a mere theoretical assumption. Attending to this fact, it should be interesting to measure how much stability preferences provide in order to improve decision making processes. Surprisingly, no research has been found on measuring preferences stability. To overcome this drawback, this paper proposes a novel approach for measuring the stability of preferences and also for improving understanding of current and future decisions. In order to be faithful to reality, this research considers decisions like complete pre-orders on a set of alternatives. Following this reasoning, this paper provides the general concept of decision stability measure as well as two specific measures: the local and the global decision stability measure. Moreover, the main features of the novel approach are examined, including several mathematical results on the behaviour of the proposed measure. And eventually, this contribution develops two real cases of study, with in-depth analysis of preferences behaviour and their stability over time. Specifically, the first one explores into the characteristics of Spanish citizens' voting behaviour and the second one attempts to analyse European citizens' preferences about passenger car market. •A general procedure to measure decisions stability over time under the assumption of complete pre-orders has been defined.•Two particular decision stability measures, the local and the global decision stability measure have been provided.•The features of the novel approaches and several mathematical results on the proposed measures have been included.•Two real cases of study have been included, the Spanish voting behaviour and the European preferences about car market.