农网10 kV配电线路拉线坑的定位计算

目前，农网完善工程中的10kV配电线路的施工过程要求，拉线与杆塔的夹角必须符合设计要求，从而保证在不同地形架设的架空线路杆塔稳定。对此，文章提出相应的拉线坑定位计算简易方法。     

Does Monetary Policy Have Asymmetric Effects on Stock Returns?

This paper investigates whether monetary policy has asymmetric effects on stock returns using Markov-switching models. Different measures of a monetary policy stance are adopted. Empirical evidence from monthly returns on the Standard & Poor's 500 price index suggests that monetary policy has larger effects on stock returns in bear markets. Furthermore, it is shown that a contractionary monetary policy leads to a higher probability of switching to the bear-market regime.     

Why do financial systems differ? History matters

We describe a dynamic model of financial intermediation in which fundamental characteristics of the economy imply a unique equilibrium path of bank and financial market lending. Yet we also show that economies whose fundamental characteristics have converged may continue to have very different financial structures. Because setting up financial markets is costly in our model, economies that emphasize bank lending are more likely to continue doing so in the future, all else equal.     

Value at risk and the cross-section of hedge fund returns

Using two large hedge fund databases, this paper empirically tests the presence and significance of a cross-sectional relation between hedge fund returns and value at risk (VaR). The univariate and bivariate portfolio-level analyses as well as the fund-level regression results indicate a significantly positive relation between VaR and the cross-section of expected returns on live funds. During the period of January 1995 to December 2003, the live funds with high VaR outperform those with low VaR by an annual return difference of 9%. This risk-return tradeoff holds even after controlling for age, size, and liquidity factors. Furthermore, the risk profile of defunct funds is found to be different from that of live funds. The relation between downside risk and expected return is found to be negative for defunct funds because taking high risk by these funds can wipe out fund capital, and hence they become defunct. Meanwhile, voluntary closure makes some well performed funds with large assets and low risk fall into the defunct category. Hence, the risk-return relation for defunct funds is more complicated than what implies by survival. We demonstrate how to distinguish live funds from defunct funds on an ex ante basis. A trading rule based on buying the expected to live funds and selling the expected to disappear funds provides an annual profit of 8–10% depending on the investment horizons.     

Pricing exotic options with L-stable Padé schemes

In this paper we develop a strongly stable (L-stable) and highly accurate method for pricing exotic options. The method is based on Padé schemes and also utilizes partial fraction decomposition to address issues regarding accuracy and computational efficiency. Due to non-smooth payoffs, which cause discontinuities in the solution (or its derivatives), standard A-stable methods are prone to produce large and spurious oscillations in the numerical solutions which would mislead to estimating options accurately. The proposed method does not suffer these drawbacks while being easy to implement on concurrent processors. Numerical results are presented for digital options, butterfly spread and barrier options in one and two assets. In addition, the methods are tested on the Heston stochastic volatility model.     

东亚区域经济合作与吉林经济发展战略的选择

放眼当今世界,东亚地区已成为最令世人瞩目的亮点之一——整个东亚地区快速崛起。在这一过程中,东亚区域经济在快速发展的同时不断地整合,地区经济合作已成为可以预期的基本趋势。面对这一有利时机和具有挑战性的机遇,吉林作为中国东亚腹地贸易通道的内陆边境地区,如何在东亚区域经济合作进程中趋利避害,找准一条切合自身发展的新路子,更好地融入东亚乃至世界经济大潮中参与合作和竞争,这是经济全球化新形势下推进吉林经济发展战略必须思考的问题。     

The Inequality of Regional Economic Development in China between 1991 and 2001

This paper measures the unequal development of the regional economies in China and investigates the primary factors leading to the inequality. The official data on China's regional GDP and the regional GDP of three industrial sectors from 1991–2001, as reported in the China Statistical Yearbook and A Statistical Survey of China, are adopted to calculate and decompose the Gini coefficient for each year. The primary finding is that the levels of inequality in China's regional economies clearly showed a slight upward trend after 1991. The inequality of the overall GDP is primarily attributed to the between-group effect rather than to the within-group effect. It is also found that the regional inequality of the secondary industry sector's development accounted for half of the overall inequality. Thus, this study suggests that it is crucial for China to formulate and adhere to policies that will help it to develop the economy more equally among all areas and to develop the secondary industry sector among all regions/provinces in order to overcome the important issue of the inequality in regional economic development.     

No Mangoes in the Tundra: Spatial Heterogeneity in Agricultural Productivity Analysis*

In line with the wider macro productivity literature existing studies of agricultural production largely neglect technology heterogeneity, variable time‐series properties and the potential for heterogeneous but correlated total factor productivity (TFP) across countries. Our empirical approach accommodates these difficulties and seeks to model the nature of the cross‐section dependence in a sample of 128 countries (1961–2002). Our results suggest that agro‐climatic environment drives similarity in TFP evolution across countries with heterogeneous production technology. This provides a possible explanation for the failure of technology transfer from advanced countries of the temperate ‘North’ to arid and/or equatorial developing countries of the ‘South’.