PORTFOLIO CHOICE VIA QUANTILES

A portfolio choice model in continuous time is formulated for both complete and incomplete markets, where the quantile function of the terminal cash flow, instead of the cash flow itself, is taken as the decision variable. This formulation covers a wide body of existing and new models with law‐invariant preference measures, including expected utility maximization, mean–variance, goal reaching, Yaari's dual model, Lopes' SP/A model, behavioral model under prospect theory, as well as those explicitly involving VaR and CVaR in objectives and/or constraints. A solution scheme to this quantile model is proposed, and then demonstrated by solving analytically the goal‐reaching model and Yaari's dual model. A general property derived for the quantile model is that the optimal terminal payment is anticomonotonic with the pricing kernel (or with the minimal pricing kernel in the case of an incomplete market if the investment opportunity set is deterministic). As a consequence, the mutual fund theorem still holds in a market where rational and irrational agents co‐exist.     

A NOTE ON THE QUANTILE FORMULATION

Many investment models in discrete or continuous‐time settings boil down to maximizing an objective of the quantile function of the decision variable. This quantile optimization problem is known as the quantile formulation of the original investment problem. Under certain monotonicity assumptions, several schemes to solve such quantile optimization problems have been proposed in the literature. In this paper, we propose a change‐of‐variable and relaxation method to solve the quantile optimization problems without using the calculus of variations or making any monotonicity assumptions. The method is demonstrated through a portfolio choice problem under rank‐dependent utility theory (RDUT). We show that this problem is equivalent to a classical Merton's portfolio choice problem under expected utility theory with the same utility function but a different pricing kernel explicitly determined by the given pricing kernel and probability weighting function. With this result, the feasibility, well‐posedness, attainability, and uniqueness issues for the portfolio choice problem under RDUT are solved. It is also shown that solving functional optimization problems may reduce to solving probabilistic optimization problems. The method is applicable to general models with law‐invariant preference measures including portfolio choice models under cumulative prospect theory (CPT) or RDUT, Yaari's dual model, Lopes' SP/A model, and optimal stopping models under CPT or RDUT.     

Eliciting Consumer Preferences for Certified Animal‐Friendly Foods: Can Elements of the Theory of Planned Behavior Improve Choice Experiment Analysis?

Models used in neoclassical economics assume human behavior to be purely rational. On the other hand, models adopted in social and behavioral psychology are founded on the “black box” of human cognition. In view of these observations, this paper aims at bridging this gap by introducing psychological constructs in the well‐established microeconomic framework of choice behavior based on random utility theory. In particular, it combines constructs developed employing Ajzen's theory of planned behavior with Lancaster's theory of consumer demand for product characteristics to explain stated preferences over certified animal‐friendly foods (AFF). To reach this objective, a Web survey was administered in the largest five EU‐25 countries: France, Germany, Italy, Spain, and the United Kingdom. Findings identify some salient cross‐cultural differences between northern and southern Europe and suggest that psychological constructs developed using the Ajzen model are useful in explaining heterogeneity of preferences. Implications for policymakers and marketers involved with certified AFF are discussed.     

Why do European consumers smoke? Responses from the rational addiction model

In this paper, we test whether European consumers are addictive smokers and, if this is the case, then whether such addictions can be explained by the rational addiction theory. To this end, we start from a non‐separable intertemporal utility function, which allows us to derive a demand function that is estimated using tobacco time‐series. The results are in accordance with the model of rational addiction for all European smokers. Thus, we observe the addictive character of tobacco consumption and, secondly, we note that the addiction is not the result of myopic consumer behaviour, but rather of the maximization of total utility, implying that consumers consider the future effects of their current decisions.     

Rational Addiction and Alcohol Consumption: Evidence from the Nordic countries

The purpose of this paper is to test Becker and Murphy's (1988) rational addiction model on 35 years of time series data on alcohol consumption in each of the four Nordic countries: Denmark, Finland, Norway, and Sweden. The empirical relevance of rational addiction theory is assessed by examining the influence of past and future consumption and contemporaneous prices on current consumption. More precisely, the rational addiction model maintains that past and future consumption should have a positive effect and that current price should have the conventional negative effect on consumption. In addition, some parameter restrictions (regarding past and future prices and consumption) implied by rational addiction are tested. Finally, the own-price elasticities from rational addiction specifications are compared to those obtained from more conventional demand specifications which ignore addiction. Ignoring addiction may provide misleading estimates of the price sensitivity of alcohol consumption and this may, in turn, lead to underestimation of the effects of major changes in price policy such as those currently taking place in the Nordic countries.     

The convenience of shopping via voice AI: Introducing AIDM

The purpose of this paper is to propose an updated view of consumer choice based on AI and inherent convenience addiction to smart speakers. Following the MacInnis framework for developing conceptual contributions of summarization, integration, and delineation, we review the current consumer decision-making literature and theory to demonstrate consumers' increasing tendency to outsource decisions to AI. Today's customers value convenience: the less time and effort they spend on a purchase, the better they perceive the transaction. AI is taking convenience to higher levels for consumers as they outsource their decisions to bots and inherent algorithms. This is particularly accurate for low-involvement everyday purchases. Our study's contribution is fourfold. First, we introduce a new model of AI-influenced decision-making (AIDM) processes. Second, our conceptual model suggests that managers need to change their interpretation of their customers' decision-making-processes in the new, AI-influenced marketplace. The shift in consumers' behavior toward reliance on home voice bots for purchase has significant implications for the retail sector. Third, our model differentiates between high and low involvement AI-influenced decision-making processes. Fourth, our study highlights how branding as we know it is challenged in an AI-dominated environment.     

Women's self-employment: An act of institutional (dis)integration? A multilevel,cross-country study

In this paper we investigate the extent to which gender equality disintegrates women's self-employment choice (compared to that for men) and whether this is contingent upon a country's development stage and industries. We rely on symbolic interactionism to argue that employment choices emerge from an interactive conversation between individual and social institutional processes. Using data from 61 countries, we find that overall gender equality is associated with the gender gap in men's and women's self-employment choices and that this association depends upon the country's development stage and industries. Contributions are made to women's entrepreneurship and institutional theory.     

SHACKLE AND MODERN DECISION THEORY

The paper discusses the role of George L.S. Shackle in fostering an unconventional approach to individual decision making. Up until the early 1970s Shackle was the single critic of the probabilistic approach to decision making who proposed an alternative formal corpus for dealing with uncertainty. The main aim of the paper is to analyse Shackle's non‐probabilistic conceptualization of individual decisions under uncertainty from a specific viewpoint, namely that of a possible connection between his theory and one of the most interesting recent approaches to decision under uncertainty, the so‐called non‐additive probability approach of Gilboa and Schmeidler. The paper shows that these developments in modern decision theory take Shackle's issue seriously and confirm that the reliance of strict Bayesian theory on probabilistic judgements based on point‐probability estimates, a reliance that Shackle intended to oppose, is untenable. Non‐additive decision theory also provides a usage of non‐additive probability distributions in choice that is an alternative to Shackle's approach of using a qualitative notion of probability, such as potential surprise.     

Competitive Features in the Provision of Consumer Credit

The sub-prime crisis has rejuvenated a public dialogue about the regulation of financial systems. This paper examines the impact of culture on the regulation of bank entry. Based on data from 53 countries, the paper's empirical estimations are inconsistent with the prediction of ‘public choice theory’, while supporting the ‘social choice view’ that cultural value has significant influence on regulatory policy and bank performance. The estimated structural model also suggests that social context can affect the formulation of cultural values across countries.     

Welfare Costs of Business Cycles in Turkey

How large are welfare costs related to economic aggregate fluctuations is a topic of great concern among economists at least since Lucas's (1987) model. Our analysis assesses the magnitude of such costs for Turkey by means of two approaches: aggregate and disaggregate. The former approach uses aggregate data employing three alternative trend‐cycle decomposition methods which are Lucas' classical set‐up with deterministic linear trend for consumption, Hodrick and Prescott filter and one in which consumption trend is stochastic and whose implementation is performed using Beveridge–Nelson decomposition. The results of both approaches suggest that Turkey has high welfare costs associated with business cycles.     

Reconciling Alternative Theories for the Safety of Owner–Operators

Motor carrier safety is an important concern of shippers, carriers, policy makers, consignees, insurance providers, and the motoring public. One aspect of carrier safety that has garnered substantial attention is whether carriers making greater use of owner–operators are more or less safe vis‐à‐vis carriers making greater use of employee drivers. Currently, conflicting theoretical predictions exist regarding the direction of this relationship. In this article, we offer a reconciliation of the alternative theoretical predictions by developing a coherent theory that merges sociological rational choice theory and theory regarding motor carrier safety. We subject our theory to empirical testing by fitting a series of seemingly unrelated regression models to a vector of safety measures tracked as part of the Federal Motor Carrier Safety Administration's Compliance, Safety, and Accountability program. Our results are consistent with our proposed theory of owner—operator safety and provide meaningful theoretical and managerial implications and directions for future research.     

New product decision making: How chance and size of loss influence what marketing managers see and do

This article empirically examines, in a new‐product decision context, the relationships among risk propensity, perceived risk, and risky choice decisions, when risk is operationalized as the chance of loss and the size of loss. The results indicate that perceptions of chance of loss directly influence choice among alternatives possessing different chances of loss and gain, whereas risk propensity directly influences choice among alternatives that differ in their size of loss and gain. The findings extend previous research by identifying dimension‐specific effects (a) between who the decision maker is and the size of an investment's potential loss, and (b) between what the decision maker sees and the chance that an investment will experience a loss. These results not only contribute to theory, but also provide marketing managers with guidance for their risky choice decisions. The composition of a new product's risk has implications for the decisions marketing managers make, for the placement of managers in risk‐sensitive positions, and for the presentation of information to individuals with oversight responsibility for the firm's product strategy decisions. © 2002 Wiley Periodicals, Inc.     

Economic science and ethical neutrality II: The intransigence of evaluative concepts

This paper returns to a perennial controversy I examined in a previous paper in the Journal of Business Ethics (Vol. 2, 1983). Is economic theory an ethically neutral discipline or do its statements presuppose a commitment to moral values? Once again this issue is addressed via a case study of the neo-classical theory of rational choice. In the present paper I focus on behaviourist forms of “operationalist” attempts to short-circuit any argument that would seek to infer moral presuppositions from the use of evaluative discourse. In particular, I examine strategies that have sought to excise from economic theory the “mentalistic” vocabulary required to describe valuations per se. And I argue that such tactics are deficient since they i) impoverish the explanatory power of economic theory, (ii) fail to recover the normative usefulness of the theory of choice, and (iii) camouflage the continued presupposition of moral commitments within neo-classical theory.     

人工智能经济学的思想端倪及建构路径

人工智能技术的广泛运用正在悄然改变人类物质文明和精神文明。文章认为人工智能对社会经济、政治、文化乃至对意识形态的影响,已经展露出可建构人工智能经济学的思想端倪。基于数字经济的发展,需要解释人工智能会在哪些方面通过市场机制对厂商投资经营发生作用;厂商运用人工智能技术究竟能在多大程度上提供有效供给和预测需求,厂商在未来普遍采用大数据分析和人工智能技术进行投资经营选择时,社会经济实践会在多大范围内要求经济学家修正微观经济学基础的理性选择理论、厂商理论和产业组织理论;假若大数据分析和人工智能技术在未来果真会引发经济学革命,经济学家如何探寻人工智能经济学的建构路径等。文章拟依据微观经济学原理对以上诸问题作出分析性描述,对有可能在理论上站得住脚的人工智能经济学的建构路径展开研究,以期达到相对前卫的理论认知。     

Distributing Start‐Up Equity: A Theoretical Foundation for an Emerging Practice

We use agency theory to model equity division in venture capital financing with three complementary value‐creation factors—the entrepreneur's effort, the venture capitalist's advising/monitoring service, and the investment amount. While considering that investors often base their funding decisions on gut feeling, even as they employ rational decision‐making processes, we derive closed‐form expressions for optimal ownership sharing. Our findings provide theoretical explanation to support the recent call for practitioners to allocate ownership equity based on the relative potential contributions of the entrepreneur and the venture capitalist to generate value for the new investment prospect.     

Measuring Effects of Trade Policy Distortions: How Far Have We Come?

After a brief review of the literature to the early 1970s, this paper assesses the contributions by economists during the past three decades to measuring the distortionary effects of trade policies. It does not pretend to be a comprehensive survey, but draws on selections from the literature that give a sense of the distance the profession has travelled from a trade policy practitioner's viewpoint since Corden's first paper on the subject in 1957. Phenomenal though that progress has been, there is ample room for further improvement in computing the economic (and other) effects of trade‐related policies and their reform. The paper concludes with suggestions of where the priorities should be in global modelling of trade policy reform, as the world moves into the next round of multilateral trade negotiations.     

De-marketing Tobacco Through Price Changes and Consumer Attempts Quit Smoking

Using panel data from three Canadian provinces, this article examines the relationship between the de-marketing of tobacco products through provincial-level price increases and consumers’ attempts to quit smoking as measured by the uptake of tobacco replacement therapies. We ground our hypotheses in the rational addiction model and the theory of planned behavior. Our analyses suggest a positive, one-month lagged effect of a price increase of tobacco products on the uptake of tobacco replacement therapies. This effect dissipates 3 months later, suggesting that there is a critical period for aggressive de-marketing of tobacco products. We discuss the implications of these results for theory and future research into de-marketing harmful consumer products.     

Cover's universal portfolio,stochastic portfolio theory,and the numéraire portfolio

Cover's celebrated theorem states that the long‐run yield of a properly chosen “universal” portfolio is almost as good as that of the best retrospectively chosen constant rebalanced portfolio. The “universality” refers to the fact that this result is model‐free, that is, not dependent on an underlying stochastic process. We extend Cover's theorem to the setting of stochastic portfolio theory: the market portfolio is taken as the numéraire, and the rebalancing rule need not be constant anymore but may depend on the current state of the stock market. By fixing a stochastic model of the stock market this model‐free result is complemented by a comparison with the numéraire portfolio. Roughly speaking, under appropriate assumptions the asymptotic growth rate coincides for the three approaches mentioned in the title of this paper. We present results in both discrete and continuous time.