We investigate what it means for one act to be more ambiguous than another. The question is evidently analogous to asking what makes one prospect riskier than another, but beliefs are neither objective nor representable by a unique probability. Our starting point is an abstract class of...

The potential of geoengineering as an alternative or complementary option to mitigation and adaptation has received increased interest in recent years. The scientific assessment of geoengineering is driven to a large extent by assumptions about its effectiveness, costs, and impacts, all of which...

This paper assessed the quantitative impact of ambiguity on historically observed financial asset returns and growth rates. The single agent, in a dynamic exchange economy, treats the conditional uncertainty about the consumption and dividends next period as ambiguous. We calibrate the agent's...

We model the learning process of market traders during the unprecedented COVID-19 event. We introduce a behavioral heterogeneous agents' model with bounded rationality by including a correction mechanism through representativeness (Gennaioli et al., 2015). To inspect the market crash induced by...

The paper shows that financial market equilibria need not exist if agents possess cumulative prospect theory preferences with piecewise-power value functions. The reason is an infiniteshort-selling problem. But even when a short-sell constraint is added, non-existence can occur due to...

Most decisions concerning (self-)insurance and self-protection have to be taken in situations in which a) the effort exerted precedes the moment uncertainty realises, and b) the probabilities of future states of the world are not perfectly known. By integrating these two characteristics in a...

Optimal portfolio rules are derived under uncertainty aversion by formulating the portfolio choice problem as a robust control problem. The robust portfolio rule indicates that the total holdings of risky assets as a proportion of the investor's wealth could increase as compared to the holdings...

This paper presents an application of a multi-attribute aggregation methodology to the construction of a sustainability index. Sustainability is a multi-faceted issue, in which synergies or conflicts may arise among the different components, thus making it a complex concept to which multi...

Composite indicators are becoming increasingly infuential tools of environmental assessment and advocacy. Nonetheless, their use is controversial as they often rely on ad-hoc and theoretically problematic assumptions regarding normalization, aggregation, and weighting. Nonparametric data...

This paper presents an application of a multi-attribute aggregation methodology to the construction of a sustainability index. Sustainability is a multi-faceted issue, in which synergies or conflicts may arise among the different components, thus making it a complex concept to which multi...