THE J CURVE: CHINA VERSUS HER TRADING PARTNERS

The short‐run effects of currency depreciation are said to be different from its long‐run effects. In the short run, the trade balance deteriorates and improvement comes after some time; hence, the J‐curve phenomenon. Previous studies that tested the response of the trade balance to exchange rate changes in China employed aggregate trade data and provided mixed results. Indeed, most of them concluded that real depreciation has no long‐run impact on the Chinese trade balance. In this paper, we disaggregate the data by country and using recent advances in time series modelling estimate a trade balance model between China and her 13 major trading partners. We show that real depreciation of the Chinese currency has a favourable impact on her trade balance with a few partners, especially the USA. Not much support is found for the J‐curve hypothesis.     

丁家屋子地区孔店组高凝油增产措施选层技术

文章通过对丁家屋子地区孔店组高凝油测试资料进行分析,将储层分为四类,并对每类储层的试油工艺及效果进行了分析,找到了增产措施选层原则。     

Problems Existed in Applications of Cointegration Theory in China

Although the Cointegration Theory was founded by the C.W.J Granger and other economists in the 1980s, it was not widely used in China until C.W.J Granger was awarded with Nobel Prize in 2003. Since then, a lot of economic papers introducing or applying Cointegration Theory have emerged, but the phenomenon of misuse of this theory possibly arose at the same time. Based on some of these papers obtained from web site （www.cnki.net）, this paper explores the applications of Cointegration Theory in China and draws some initial conclusions. Most of these applications are reasonable, but some of them are a bit blindfold or even contradictory in conclusions, which indicates that the overall application quality has a large room to get improved and should be paid more attention by academe.     

Minimax character of the two-sample χ2-test

Abstract  We consider the problem of testing equality of the mean vectors of two multivariate normal populations when covariates are present and the covariance matrix is known. As an application of the H unt -S tein theorem it is shown that the χ²-^-test of level a maximizes, among all level a tests, the minimum power on each of the contours where the χ²-^-test has constant power. A corollary is that the χ²-^-test is most stringent level a .     

The residual market factor,the APT,and mean-variance efficiency

The rapidly increasing volume of both published and unpublished work on the arbitrage pricing theory (APT) of Ross (1976) has given rise to a number of misunderstandings at the interface of theoretical and econometric work. In this article we extend the theoretical structure of our previous work (McElroy and Burmeister, 1985, 1988; Burmeister and McElroy, 1987, 1988) to provide a broad yet rigorous framework both for econometric estimation and for better economic interpretation of new empirical results. We begin with the case where allK factors are observed, and then present the second case ofK−1≡J observed APT factors and one unobserved factor, theresidual market factor introduced in McElroy and Burmeister (1985). The economic interpretations for equivalent specifications of this model are discussed, and we enumerate several immediate payoffs to these specifications. The main new results are concerned with the sometimes intricate relationships among APT models withK factors and APT models withK factors that are constrained to satisfy mean-variance efficiency restrictions. These results are not only of theoretical interest, but more importantly they provide the basis for econometric estimation and testing of nested hypotheses. These econometric issues are discussed in detail.     

压力测试与反向压力测试在银行风险管理中的运用

压力测试作为一般风险计量工具的重要补充,越来越受到金融监管部门和银行业的重视。文章从压力测试和反向压力测试的原理与方法出发,比较分析压力测试与在险价值(VaR)的特征性与互补性,通过示例阐明压力情景的设置方法和压力测试的操作过程,并探讨压力测试和反向压力测试在银行风险管理中的实务问题。     

关于压裂支撑剂评价实验的若干思考

水力压裂是油气井增产、水井增注的有效措施,压裂支撑剂性能的好坏直接影响人工裂缝的导流能力。在从事支撑剂性能评价试验中,发现若干对支撑剂性能评价试验的影响因素。研究结果对压裂支撑剂的评价标准以及下一步有效地改进具有重要的指导意义。     

HPKL液流转向剂安全性能测试

为了更好地控制高含水油田注采无效循环,油田迫切需要开展深部液流转向与调驱技术研究,通过注入化学剂迫使液流转向,降低油水界面张力达到驱油效果。目前常用化学剂有上百种,且大多数都是聚合物合成的高分子材料,其对环境伤害的程度各不相同。分析了HPKL转向剂急性中毒性测试、生物累积性测试实验的过程和结果,测得了HPKL的EC50值;确定了HPKL转向剂生物毒性为低毒、无生物累积,对环境损害程度小。     

浅层出砂井地层测试工艺探讨与应用

为解决海上油井浅层出砂井中封隔器密封性和座封、出砂控制、排液方式等问题,根据浅层出砂井的地质特征,通过增加管柱重量、优选测试工具及管柱设计、排液方式等测试工艺措施,探讨了螺杆泵排液＋钻铤＋测试阀测试管柱结构的可行性,通过现场应用,该测试工艺在浅层出砂井中具有极强相容性及优越性。     

The search for asterisks: Compromised statistical tests and flawed theories

This paper discusses repeated tests and the resultant reporting of statistical significance when it is actually not present. These errors interact with professional norms such as biases against both replication studies and ‘non‐results’ to undermine the efficacy of our base of empirically tested theory. This raises serious issues for the future of strategic management research. Suggestions are made for dealing with these issues substantively and in terms of professional norms. Copyright © 2011 John Wiley & Sons, Ltd.