Does Uncertainty of Firing Costs Reduce Hirings?

This paper examines hiring decision under uncertainty of firing costs. We extend the labor demand problem of the firm to account for a random shock that hits the firing cost function. We also consider recursive preferences for the employer in order to separate risk aversion from intertemporal substitution. We find that a rise of the variance of the shock decreases hiring investment if and only if the intertemporal elasticity of substitution is greater than one. The risk aversion parameter does not determine the sign of the uncertainty effect but only its magnitude.     

A bayesian estimator for the dependence function of a bivariate extreme‐value distribution

Any continuous bivariate distribution can be expressed in terms of its margins and a unique copula. In the case of extreme‐value distributions, the copula is characterized by a dependence function while each margin depends on three parameters. The authors propose a Bayesian approach for the simultaneous estimation of the dependence function and the parameters defining the margins. They describe a nonparametric model for the dependence function and a reversible jump Markov chain Monte Carlo algorithm for the computation of the Bayesian estimator. They show through simulations that their estimator has a smaller mean integrated squared error than classical nonparametric estimators, especially in small samples. They illustrate their approach on a hydrological data set.     

On diagnostic checking of the autoregressive conditional intensity model

The autoregressive conditional intensity model proposed by Russell (1998) is a promising option for fitting multivariate high frequency irregularly spaced data. The authors acknowledge the validity of this model by showing the independence of its generalized residuals, a crucial assumption of the model formulation not readily recognized by researchers. The authors derive the large‐sample distribution of the autocorrelations of the generalized residual series and use it to construct a goodness‐of‐fit test for the model. Empirical results compare the performance of their test with other off‐the‐shelf tests such as the Ljung–Box test. They illustrate the use of their test with transaction records of the HSBC stock.     

Analysis of breeding bird communities along an urban-rural gradient in Berlin,Germany, by Hasse Diagram Technique

Breeding bird communities in Berlin were investigated at five study sites, which represent an structural urban-rural gradient, from densely built-up areas with sealed ground to green areas such as large parks. In this paper, we tested the Hasse Diagram Technique (HDT), an approach belonging to partial order theory, for its appropriateness to extract information about changes in species composition from our data set. As expected, the overall number of bird species was positively correlated with the urban-rural gradient, increasing from 12 found in the city center to 28 in an urban park. By HDT analysis, four different sub-groups of birds could be identified, contributing differentially to the increase in species number: (1) ubiquists, i.e., species found at each study site, (2) a sub-group, the species’ number of which was positively correlated with the urban-rural gradient, increasing with increasingly green areas, (3) a sub-group, the species’ number of which was negatively correlated with the urban-rural gradient, decreasing with a declining density of buildings, and (4) species, the distribution of which did not show any correlation with the urban-rural gradient. The results show that HDT is a suitable tool for formalized analysis of the pattern of species’ communities along an environmental gradient.     

Community Reactions to Young People Who Have Sexually Abused and Their Families: A Shotgun Blast,Not a Rifle Shot

Data on 117 young sexual abusers were examined to investigate the nature of community responses to young people's abusive behaviour. A wide range of community responses were found, with stigmatisation, social isolation and collateral damage being common. A contagion effect was noted, with community responses extending over time and across contexts. Some young offenders and their families were attacked and forced out of their homes. In some cases, community responses heightened risk factors. The policy and practice implications of the findings are discussed, including the need for caution about the inclusion of children in policies on community notification of sex offenders.     

Examining reports and policies on cognitive enhancement: approaches, rationale, and recommendations

The phenomenon of cognitive enhancement is attracting attention in bioethics literature and beyond, in public policy. In response, three bodies--the British Medical Association (BMA); the Commission de l'éthique de la Science et de la technologie (CEST) du Québec; the American Academy of Neurology (AAN)--have produced reports and guidance on this topic. To gain insights into different public policy approaches, rationales, and recommendations on the topic, we analyzed these reports in depth. We found convergence on the definition (with the exception of the CEST) of cognitive enhancement. However, we noted a lack of critical reflection with respect to the underlying rationale for developing these reports, i.e., that cognitive enhancement practices are rampant and represent major social changes. As it currently stands, cognitive enhancement is constituted in a way that challenges the creation of coherent and effective policy recommendations. However, policy makers should not simply wait for definitional consensus and hope that on balance the benefits turn out to be greater than the risks. Some components of cognitive enhancement could be reduced down to clearly identified policy targets to be further examined. Then, if appropriate, policy should be created that is, amongst other criteria, beneficial to the majority of the population.     

你与全球气候变化——全球二十余位顶尖级专家学者谈人类活动与全球气候变化的关系

性别与气候变化政策妇女是最容易受到气候变化影响的人群之一,这一点已为人们普遍接受。但多年来,人们却一直在忽视性别问题,一直在讨论制度问题而不是人的问题。现在,性别问题又逐渐提上日程。造成性别不平等的一个主要因素是劳动的性别分工。不管在发展中国家或