Voters’ preference diversity, concepts of agreement and Condorcet’s paradox

International audienceGehrlein et al. (Math Soc Sci 66:352–365, 2013) have shown that an increase of the voters’ preference diversity, as measured by the number kkk of preference types in a voting situation, implies a decrease in the probability of having a Condorcet Winner. The results offered in this paper indicate that this relationship is far from being so clear when we consider instead the proximity of voting situations to having kk distinct preference types. This measure of agreement is compared to other measures of group mutual coherence previously analyzed in Gehrlein (Condorcet’s paradox, Springer Publishing, Berlin, 2006). It turns out that our results are completely consistent with the theory introduced by List (Good Soc 11:72–79, 2002) that is based on an important distinction between two different concepts of agreement