Regier DA, Sicsic J, Watson V. Choice certainty and deliberative thinking in discrete choice experiments. A theoretical and empirical investigation. J Econ Behav Organ. 2019 Aug;164:235-55. doi: 10.1016/j.jebo.2019.05.031
Cropper ML, Haile M, Lampietti J, Poulos C, Whittington D. The demand for a malaria vaccine: evidence from Ethiopia. J Dev Econ. 2004 Oct 1;75(1):303-18.