This paper focuses on the comparison of individual and group decision-making, in a stochastic inter-temporal problem in two decision environments, namely risk and ambiguity. Using a consumption/saving laboratory experiment, we investigate behaviour in four treatments: individual choice under risk; group choice under risk; individual choice under ambiguity and group choice under ambiguity. Comparing decisions within and between decision environments, we find an anti-symmetric pattern. While individuals are choosing on average closer to the theoretical optimal predictions, compared to groups in the (...) risk treatments, groups tend to deviate less under ambiguity. Within decision environments, individuals deviate more when they choose under ambiguity, while groups are better planners under ambiguity rather than under risk. Our results extend the often observed pattern of individuals behaving more optimally under risk, to its dynamic dimension. (shrink)

We analyze the results from three different risk attitude elicitation methods. First, the broadly used test by Holt and Laury, HL, second, the lottery-panel task by Sabater-Grande and Georgantzis, SG, and third, responses to a survey question on self-assessment of general attitude towards risk. The first and the second task are implemented with real monetary incentives, while the third concerns all domains in life in general. Like in previous studies, the correlation of decisions across tasks is low and usually statistically (...) non-significant. However, when we consider only subjects whose behavior across the panels of the SG task is compatible with constant relative risk aversion, the correlation between HL and self-assessed risk attitude becomes significant. Furthermore, the correlation between HL and SG also increases for CRRA-compatible subjects, although it remains statistically non-significant. (shrink)

We use a controlled laboratory experiment to study firm’s protection against potential technological damages. The probability of a catastrophic event is known, and the firm’s costly investment in safety reduces it. The firm can also buy an insurance with full or partial refund against the consequences of the catastrophic event, which ultimately reduces the variance of the firm’s investment-in-safety lottery. The firm makes these two choices simultaneously, after observing the insurance contract proposed by an insurer who chooses this contract within (...) a set of premium–deductible combinations. We parametrize the insurer–firm game such that a risk-neutral insurer maximizes his expected profit by offering an actuarially fair contract with full insurance; a risk-neutral firm is indifferent between investing in safety and accepting a fair insurance contract. We aim at understanding whether investment in safety and insurance are substitutes or complements in the firm’s risk management of catastrophic events. In line with our predictions, the experimental results suggest that they are substitutes rather than complements: the firm’s investment in safety measures is affected by the insurer’s proposed contract, the latter usually involving only partial insurance. (shrink)

The objective of this study is to design a laboratory experiment to explore the effect of ambiguity on a subject’s search behavior in a finite-horizon sequential search model. In so doing, we employ a strategy to observe the potential trend of reservation points that is usually unobserved. We observe that subjects behaving consistently across treatments reduce their reservation points in the face of ambiguity over point distribution. Our result is consistent with the theoretical implication obtained by Nishimura and Ozaki.