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.     

层次分析法在沼气厂址选择中的应用

本文运用层次分析法对影响沼气厂址选择的因素进行综合分析,通过量化,将复杂的选址问题统筹简化为各种因素之间的成对比较和排序计算,建立数学参数模型,使得厂址选择达到最优。     

A dimensionally consistent aggregation framework for biophysical metrics

We develop a formal representation of the economy-ecosystem interaction problem by distinguishing between stock-flow, and fund-flux spaces (Georgescu-Roegen, 1971). We then define dimensionless quantities in both the cardinal stock-flow space and the ordinal fund-flux space. This leads to analytic definitions of natural capital and natural income in the fund-flux space. We show that a stock-fund representation of the economy-ecosystem interaction problem helps investigate aggregation properties of biophysical metrics. In particular, we show how a metric that is dimensionally consistent in the stock-flow space can have dimensional problems in the fund-flux space. Ecological footprint is used as an illustrative example. Finally, we argue that dimensionally consistent metrics are keys to further the development of biophysical assessments as a tool for practical environmental policy.     

How would Swiss consumers decide if they had freedom of choice? Evidence from a field study with organic,conventional and GM corn bread

In 2005, the Swiss expressed their negative attitude towards genetic engineering in agriculture by voting in favor of a ban to use genetically modified (GM) crops in domestic agriculture. At the same time, certain GM food products remain approved but are not on offer since retailers assume that consumers would shun labeled GM food. In our study we tested this claim by conducting a large-scale field study with Swiss consumers. In our experimental design, three clearly labeled types of corn bread were offered at five different market stands across the French and German-speaking part of Switzerland: one made with organic, one made with conventional, and one made with genetically modified (GM) corn. In addition, we tested the consistency between purchasing decision at the market stand and the previous voting decision on GMOs in 2005 by means of an ex-post questionnaire. The results of our discrete choice analysis show that Swiss consumers treat GM foods just like any other type of novel food. We conclude from our findings that consumers tend to appreciate transparency and freedom of choice even if one of the offered product types is labeled as containing a genetically modified ingredient. Retailers should allow consumers to make their own choice and accept the fact that not all people appear to be afraid of GM food.     

Buying cooperation in an asymmetric environmental differential game

We consider a two-player asymmetric differential game of pollution control. One player is non-vulnerable to pollution, or unwilling to consider damages when choosing her production policy in a non-cooperative game. We characterize the feedback-Nash equilibrium and the cooperative solution. We establish conditions under which the vulnerable player can buy the cooperation of the non-vulnerable player to control her emissions. We further use the Nash bargaining solution to allocate the total cooperative dividend between the two players and propose a time-consistent decomposition overtime of the total payoff.     

Rethinking Internal Consistency in Cronbach's Alpha

Stress is one byproduct of hectic and busy lives. Therefore, examining active living and leisure in relation to stress and coping offers an important area of study. This paper presents key findings from a multi-year qualitative study of stress and coping. A series of focus groups were conducted with diverse residents of a western Canadian city including: (a) Aboriginal individuals with diabetes, (b) individuals with disabilities, and (c) people who identified as gay or lesbian. The findings emphasized that active leisure is more than physical activity, and that less physical forms of leisure should not be undervalued in the conceptualization of active living and leisure. Coping with stress using active leisure encompassed a wide range of meanings (e.g., spiritual, social, cultural, altruistic, empowerment).     

A Test for Natural Monopoly with Application to Norwegian Electricity Distribution

Review of Industrial Organization - Reorganization of public utilities is on the currentpolitical agenda in many European countries. However,in many cases the most fundamental question in termsof...     

Finite sample properties for the semiparametric estimation of the intercept of a censored regression model

Financial support for this paper was provided by a C.A. Anderson Fellowship of the Cowles Foundation. I wish to thank Donald Andrews, Moshe Buchinsky, Oliver Linton, and Peter Robinson for helpful discussions. I also wish to thank three anonymous referees for their comments and suggestions. I am, of course, responsible for any remaining errors. A popular two-step estimator of the intercept of a censored regression model is compared with consistent asymptotically normal semiparametric alternatives. Using a root mean squared error criterion, the semiparametric estimators perform better for a range of bandwidth parameter choices for a variety of distributions of the errors and regressors. For error distributions that are close to the normal, however, the two-step parametric estimator performs better.     

On the estimation of the parameters for the Littlewood model in software reliability

A very well-known model in software reliability theory is that of Littlewood (1980). The (three) parameters in this model are usually estimated by means of the maximum likelihood method. The system of likelihood equations can have more than one solution. Only one of them will be consistent, however. In this paper we present a different, more analytical approach, exploiting the mathematical properties of the log-likelihood function itself. Our belief is that the ideas and methods developed in this paper could also be of interest for statisticians working on the estimation of the parameters of the generalised Pareto distribution. For those more generally interested in maximum likelihood the paper provides a 'practical case', indicating how complex matters may become when only three parameters are involved. Moreover, readers not familiar with counting process theory and software reliability are given a first introduction.     

Generalizations of the KPSS-test for stationarity

We propose automatic generalizations of the KPSS-test for the null hypothesis of stationarity of a univariate time series. We can use these tests for the null hypotheses of trend stationarity, level stationarity and zero mean stationarity. We introduce the asymptotic null distributions and we determine consistency against relevant nonstationary alternatives. We compare the properties of the tests with those of other proposed tests for stationarity. Monte Carlo simulations support the relevance of the tests when an autoregressive process with large positive autocorrelations is likely under the null hypothesis.