Violations of monotonicity in choices between gambles and certain cash

Recent studies found that judgments of the values of gambles violated monotonicity (a form of dominance). There are gambles for which an increase in the value of one outcome; holding everything else constant, causes a decrease in the judged value of the gamble. This paper replicates and extends recent work with choices between gambles and a fixed set of amounts of money that would be received for certain. A set of relations is defined on choice proportions as follows: A curly greater than B-c (Gamble A is preferred to B on relation c) if and only if the proportion of choices favoring amount c over Gamble A is less than the proportion choosing cover B. Results replicate previous findings in which these choice-based certainty equivalents violate monotonicity. The new relation also reveals systematic violations of monotonicity when c is greater than the minimum outcome of the superior gamble, but not when c is less than this value. this result helps clarify the conditions under which monotonicity is violated.