Decision Research on Time, Risk, and Ambiguity

This dissertation consists of three essays. The first essay explores how to counteract the uncertainty effect bias by appropriately manipulating either the anchoring process or the adjustment process involved in the bias. First, I examine how providing an anchor prior to judging the value of the lottery affects individuals' judgments, and find that anchoring on the worst outcome counteracts the uncertainty effect. Then I investigate if omitting information about the probability of the outcomes to create an ambiguous lottery affects individuals' judgments, and find that this is not sufficient to counteract the uncertainty effect. Finally, I explore if introducing additional cognitive load dampens over-adjustment and thus affect individuals' judgments, and find that additional cognitive load is able to counteract the uncertainty effect bias.;In an intertemporal choice context, the second essay investigates decision makers' subjective perception of the temporal duration between now and the time they would receive future payments. I show that participants' subjective perceptions of temporal duration are not independent of the outcome magnitudes, where larger monetary outcomes are associated with shorter subjective time perception (experiments 1&2). Furthermore, this difference in temporal perception can help us explain the magnitude effect. My results replicate the magnitude effect when taking only objective time into account but show a constant discount rate when taking subjective time perception into account (experiment 3).;The third essay investigates the impacts of an ambiguous time on decision making over time. In the first experiment, employing hypothetical scenarios and a between-subjects design, I found that in some situations, decision makers may discount more when facing an ambiguous time delay than facing the end of the ambiguous span. Furthermore, a reversed magnitude effect, the gain/loss asymmetry, and the short term/long term asymmetry phenomenon were observed in experiment 1. In experiment 2, I tested the effects we found in experiment 1 with real payoffs. First, the observed effect that people over-discount an outcome with an ambiguous realizing time was found only in individual level data analyses. Second, I found that the short term/long term asymmetry appeared in all cases across different conditions and experiment design.