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.     

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.     

Distance sampling methodology

We consider the method of distance sampling described by Buckland, Anderson, Burnham and Laake in 1993. We explore the properties of the methodology in simple cases chosen to allow direct and accessible comparisons of distance sampling in the design- and model-based frameworks. In particular, we obtain expressions for the bias and variance of the distance sampling estimator of object density and for the expected value of the recommended analytic variance estimator within each framework. These results enable us to clarify aspects of the performance of the methodology which may be of interest to users and potential users of distance sampling.     

Estimation of relaxation time distributions in magnetic resonance imaging

Magnetic resonance imaging techniques can be used to measure some biophysical properties of tissue. In this context, the T₂ relaxation time is an important parameter for soft‐tissue contrast. The authors develop a new technique to estimate the integral of the distribution of T₂ relaxation time without imposing any constraint other than the monotonicity of the underlying cumulative relaxation time distribution. They explore the properties of the estimation and its applications for the analysis of breast tissue data. As they show, an extension of linear discriminant analysis is found to distinguish well between two classes of breast tissue.     

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     

The Presentation of Avatars in Second Life: Self and Interaction in Social Virtual Spaces

What do interactions in virtual spaces suggest about everyday life in the digital age? How do interactions in virtual spaces shape everyday life in the digital age? Guided by hypermodern theory, I conduct participant observation in the social virtual world Second Life to provide tentative answers to those questions. I suggest that Second Life is both a social psychological playground where participants enjoy individualistic fantasies and a virtual community where they collaborate on collective projects. When people define the virtual as real, it is real in its consequences. Accordingly, social virtual spaces such as Second Life offer sociologists unique opportunities for research, education, intervention, and hence the development of a virtual imagination.     

The End of the World Designed with Men in Mind

According to Derrida, the European self-understanding marking the name “Man” is governed by eschatology and teleology. Man is that being on its way towards its proper end. The times of science seemed to Kant and others to be evidence of just such progress. For Freud, by contrast, the great scientific achievements of Copernicus, Darwin and Freud have cumulatively contributed a series of de-centring blows to our “self-love”. This paper explores the nature of great scientific achievements, and raises the possibility of a further devastating blow to Man, this time in the twentieth century, and connected to the name of Marx.