钻石理论模型述评

在对波特钻石理论模型概述后，主要从卡特赖特（Cartwright）的多因素钻石模型，邓宁（Dunning）的国际化钻石模型，鲁格曼和克鲁兹（Rugman，Cruz）的双钻石模型，穆恩、鲁格曼和沃伯克（Moon，Rugman，Verbeke）的一般化的双重钻石模型，乔东逊（Cho．D．Sung）的九要素模型等方面对波特钻石理论模型的拓展进行了综述，对波特钻石理论模型作了评论，并对模型进行了修正。     

Critical representations of Southern African inequality: Transcending outmoded exhibition and museum politics

ABSTRACT

Illustrating inequality to a more general public – beyond those concerned purely with public policy and research – presents various challenges. Museums have often served a function of memorialising both the impressive steps forward and major barriers to social progress, as a form of remembrance and understanding, although the twentieth century format in South Africa was generally embedded within colonial and racist self-glorification. The potential to transcend outmoded exhibition and museum politics with a new approach based on dialogical not didactic presentation, arises with inequality. In this exploration of how such an approach might unfold in the world's most unequal major city (as judged by the Palma Ratio), Johannesburg, the concept of threshold is introduced. Physical and conceptual access through overcoming thresholds is explored through a specific site, the Old Post Office, and through two artifacts that reveal structural power that generates inequality: Durban's sanitation system and Eastern Zimbabwe's diamond fields.     

Diamonds and precious metals for reduction of portfolio tail risk

ABSTRACT

We study the performance of diamonds compared to gold and other precious metals in mitigating the tail risk of a diversified equity market portfolio over the period June 2007 to October 2018. Our results display a diversification benefit of some diamond indices, which also improve the portfolio reward-to-risk ratio. To corroborate this evidence, we study the dependence structure and tail dependence of diamonds and a broad equity market portfolio and compare it to the dependence obtained with gold and other precious metals. Results from fitting a bivariate copula show that the average left tail dependence reaches its minimum when diamonds are used. We also show that using shares of diamond-mining companies does not provide the same benefits.