THEORIES OF CHOICE UNDER IGNORANCE AND UNCERTAINTY

Abstract. In this paper, Knight's distinction between risk and uncertainty, and its significance for economic analysis are examined. The paper consists of a survey of some recent developments on the theory of choice under uncertainty and some applications of these theories to problems for which Bayesian Decision Theory has not proved entirely satisfactory. Two problems are examined in detail. The first is that of finance and insurance and the second is that of risktaking behaviour with special emphasis on lotteries.     

Completing the State Space with Subjective States

We define an opportunity act as a mapping from an exogenously given objective state space to a set of lotteries over prizes, and consider preferences over opportunity acts. We allow the preferences to be possibly uncertainty averse. Our main theorem provides an axiomatization of the maxmin expected utility model. In the theorem we construct subjective states to complete the objective state space. As in E. Dekel et al. (Econometrica, in press), we obtain a unique subjective state space. We also allow for preference for flexibility in some of the subjective states and commitment in others. Journal of Economic Literature Classification Number: D81.     

Decision-making in incomplete markets with ambiguity—a case study of a gas field acquisition

We apply utility indifference pricing to solve a contingent claim problem, valuing a connected pair of gas fields where the underlying process is not standard Geometric Brownian Motion and the assumption of complete markets is not fulfilled. First, empirical data are often characterized by time-varying volatility and fat tails; therefore, we use Gaussian generalized autoregressive score (GAS) and GARCH models, extending them to Student’s t-GARCH and t-GAS. Second, an important risk (reservoir size) is not hedgeable. As a result, markets are incomplete which makes preference free pricing impossible and thus standard option pricing methodology inapplicable. Therefore, we parametrize the investor’s risk preference and use utility indifference pricing techniques. We use Least Squares Monte Carlo simulations as a dimension reduction technique in solving the resulting stochastic dynamic programming problems. Moreover, an investor often only has an approximate idea of the true probabilistic model underlying variables, making model ambiguity a relevant problem. We show empirically how model ambiguity affects project values, and importantly, how option values change as model ambiguity gets resolved in later phases of the projects. We show that traditional valuation approaches will consistently underestimate the value of project flexibility and in general lead to overly conservative investment decisions in the presence of time-dependent stochastic structures.     

Causal Ambiguity in Lean Production Implementation in Malaysia

The success of the lean production system in Japan has led other companies to attempt to adopt it. Yet lean production system initiatives have seen a low success rate. This study draws on the theory of causal ambiguity and its role in the transfer of knowledge to argue that causal ambiguity can impede interfirm transfer of knowledge during lean production system implementation. The authors argue that causal ambiguity undermines motivation during lean production system implementation. Several variables are proposed as moderating the relationship. The findings of a survey are presented here.     

汉语成语中数字模糊性的理解及其行文翻译

汉语成语中的数字所表达的数量概念具有模糊性.在数词构成的汉语成语的行文翻译时,既要考虑结构的形式,更要注重数字所蕴含的模糊表意功能,处理好"形"与"意"之间的关系.     

The influence of risk preferences,knowledge, land consolidation,and landscape diversification on pesticide use

Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.     

Migration decisions under ambiguity: Migration distance effects revisited

There is ample evidence that distance has a strong negative effect on migration. Despite its significance in migration decisions, scholars rarely explore the migration distance effect deeper than the first level of interpretation derived from the simple neoclassical theory of migration. This study revisits the migration distance effect in the spirit of Knightian distinction between risk and uncertainty. To this end, this study attempts to construct estimates of the risk premium migrants are willing to pay to avoid the risk associated with migration distance. The results show that the magnitude of the distance effect is not rationalized by risk aversion in the Arrow–Pratt sense (Arrow, 1965, The theory of risk aversion, Yrjo Jahnssonin Saatio, Helsinki, Finland, 90; Pratt, 1964, Econometrica, 32, 122). In particular, the risk premium demanded by distant rural residents is unjustifiably higher compared with that of those living closer to urban areas in their migration decisions. The results suggest that the migration distance effect is analogous to the equity home bias puzzle and the Ellsberg paradox in that the assumption of subjective expected utility can lead to seemingly irrational human behaviors. Some of the findings in this study shed light on the role of subjective aspects such as perception, confidence, and pessimism in migration decisions, which have been neglected in the literature.     

The influence of service orientation discrepancy between managers and employees on employees’ affective outcomes

This study attempted to relate service orientation discrepancy (SOD) between employees and managers to employees’ affective reactions [role conflict (RC), role ambiguity (RA), job satisfaction (JS), and organizational commitment (OC)] in the restaurant industry. The findings of the study indicate that there is a SOD between managers and employees; employees saw themselves as more enthusiastic and less bureaucratic than managers. When this SOD was correlated with employee outcomes such as RC, RA, JS, and OC, the results indicated that SOD had a direct effect on RC, JS and OC. SOD also had indirect effects on JS, and OC through RC and RA. RC had a direct effect on JS and an indirect effect on OC. RA had a direct effect on JS. Finally, JS had a direct effect on OC.     

The Valuation of Insurance under Uncertainty: Does Information about Probability Matter?

In a laboratory experiment we test the hypothesis that consumers' valuation of insurance is sensitive to the amount of information available on the probability of a potential loss. In order to test this hypothesis we simulate a market in which we elicit individuals' willingness to pay to insure against a loss characterised either by known or else vague probabilities. We use two distinct treatments by providing subjects with different information over the vague probabilities of loss. In general we find that uncertainty about probabilities has a weak impact on consumers' valuation of insurance. However, additional information about probabilities tends to marginally increase the price individuals are willing to pay to insure themselves. Implications for the insurance market are derived.     

Brand equity in the professional service context: Analyzing the impact of employee role behavior and customer-employee rapport

The study examines whether factors related to customers' perception of employees' behavior in terms of customer perceived role ambiguity, role overload and customer-employee rapport influence the development of brand equity in the professional service context. 632 customers of one of the Big Four auditing companies participated in the study. The results of structural equation modeling show negative effects of role ambiguity and role overload on brand associations, perceived quality and brand loyalty, which constitute brand equity. The findings indicate a positive effect of customer-employee rapport on the enhancement of B2B brand equity. However, the negative influences of role ambiguity and role overload on customer-employee rapport transfer detrimental indirect effects on brand equity. The study contributes to an understanding of how the real interaction between service providers and customers can influence brand equity in the professional service setting.