Asymmetric payoffs in simultaneous and sequential prisoner’s dilemma games

We investigate the role of payoff asymmetry in laboratory prisoner’s dilemma games. Symmetric and asymmetric games are examined in simultaneous and sequential settings. In the asymmetric sequential games, we study the impact of having payoff advantaged players moving either first or second. Asymmetry reduces the rates of cooperation in simultaneous games. In sequential games, asymmetry interacts with order of play such that the rate of cooperation is highest when payoff disadvantaged players move first.     

Brain Politics: Aspects of Administration in the Comparative Issue Definition of Autism-Related Policy

The construction of public problems has a lasting influence on implementation in a given policy subsystem. National and sociopolitical contexts influence issue definition differently across nations. However, the degree to which nation-specific issue definition takes place has been insufficiently explored. In recent years, the growing incidence of autism has led to a quest for causal factors. One hypothesis posits that the use of mercury in vaccines may be a culprit. This paper examines the definition of the mercury and autism issue in Australia, Canada, the United Kingdom, and the United States. Insights into the comparative elements of issue definition are suggested by the case. These insights are of particular importance to administrators, as agencies are deeply involved as objects and actors in the process of issue definition and are often responsible for implementing new and redefined policies.     

On the optimal retaliation against terrorists: The paid-rider option

We examine whether nations, faced with the threat of terrorism, will be motivated to engage in the efficient amount of retaliation against terrorists. We demonstrate that the problem confronting the efforts of nations to achieve an optimal retaliation against terrorists is understated by the traditional free-rider analysis. In particular, nations have the option of actually selling or reducing the public good of retaliation, provided through the efforts of others, by offering safe havens to terrorists in return for the terrorists' pledge to attack elsewhere. This paid-rider behavior is also shown to apply to other public good scenarios.The authors gratefully acknowledge the helpful comments of Gordon Tullock on an earlier draft. Sole responsibility for the paper's content rests with the authors. Todd Sandler's research was supported by a Science and Humanities Research Institute Summer Grant at Iowa State University.     

Chinese migrant women and families in Britain

This article examines the mode of understanding and experiences of family relationships of Chinese migrant women in Britain. In contrast to much existing research work on the patterns and experiences of postwar settlement of unskilled Chinese male labourers in Britain, the focus here is on the life stories of 41 Chinese women with different migration trajectories and varying economic and cultural capital. Their oral testimonies reveal Chinese women's diverse expectations and experiences of migrant family relationships and their different strategies to achieve self-fulfillment both within and outside the confines of the migrant family. For some women, migration brings opportunities for a fulfilling and independent lifestyle. They are successful in negotiating their way around and sometimes out of their initial familial and social position. For others, they bear the disproportionate cost and labour of familial strategies of advancement and remain vulnerable to the most constraining aspects of diasporic existence.     

Enantiomeric separation of methamphetamine and related analogs by capillary zone electrophoresis: intelligence study in routine methamphetamine seizures

A method for simultaneous enantiomeric separation of ephedrine, pseudoephedrine, and methamphetamine (MA) in a single run by simple capillary zone electrophoresis (CZE) with beta-cyclodextrin as a chiral selector is described. The effects of the buffer pH, phosphate concentration, beta-cyclodextrin concentration, voltage and temperature on the peak resolution were examined. Good enantiomeric resolution was attained for each analyte under our optimized conditions: 15 mM beta-cyclodextrin, 300 mM NaH2PO4 at pH 2.5 with an uncoated capillary (64.5 cm x 50 microm), applied potential at 20 kV and temperature at 30 degrees C. Ultraviolet (UV) detection at a fixed wavelength (200 nm) was employed using a diode array detector. Using phentermine as an internal standard, migration times for all analytes are reproducible within 0.16% for intra-day and 0.6% for inter-day runs. Application of this method to the analysis of confiscated drugs is discussed.     

浅议环境对汉语学习的影响

环境对学习语言非常重要,充分利用社会大环境,创造良好的课堂小环境,发挥学生自然习得的作用,建立课堂教学与自然习得相结合的新教学体系,这是提高教学效果的重要途径。