Possibility of 22 < -3/2 for three-element permutations with m > 3
Determine whether the swap-distance optimality score 22, defined as 22 = ((d)r - (d))/((d)r - (d)min) where (d) is the average swap distance for a given arrangement, (d)r is the expected value under a random permutation of the same probabilities, and (d)min is the minimum over all permutations, can take values strictly smaller than -3/2 in the case n = 3 (three constituents) when the number of non-zero probability orders satisfies m > 3.
References
Thus the open problem is if 22 can be smaller than -3/2 when n = 3 and m > 3.
— How to measure the optimality of word or gesture order with respect to the principle of swap distance minimization
(2604.01938 - Ferrer-i-Cancho, 2 Apr 2026) in Appendix B, subsection 3. Lower bounds of 22 (following Property B.5)