URL des Documents de travail : https://centredeconomiesorbonne.univ-paris1.fr/documents-de-travail-du-ces/Documents de travail du Centre d'Economie de la Sorbonne 2019.07 - ISSN : 1955-611XUsing discrete choices to elicit preferences is a major tool to help guide public policy. Although Discrete Choice Experiment (DCE) remains by far the most popular mechanism used to elicit preferences, its reliability still is questionable. Using an induced value experimental design, we show that standard benchmarks achieve no more than 56% (hypothetical answers with no monetary incentives) to 60% (real monetary incentives) of payoff maximizing choices. Herein we demonstrate that having respondents sign a the truth-telling oath reduces non-payoff maximizi...