Understanding the impacts of ‘Grain for Green’ land management practice on land greening dynamics over the Loess Plateau of China

Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO₂ and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO₂ concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO₂ concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning.     

A Note on the Joint Distribution of α, β-Percentiles and Its Application to the Option Pricing

In this paper, using Laplace transform, we will calculate the joint density of twopercentiles of stock prices in the Black–Sholes model and make the price of exchange options of such twopercentiles.     

Estimating the term structures of corporate debt

This paper investigates the corporate bond market by estimating monthly interest rate term structures for investment grade credit classes using both S&P's and Moody's ratings. Term structures are modeled by a piecewise constant forward rate curve and estimated on noncallable coupon paying bonds issued by industrial firms. The iterative estimation algorithm minimizes the sum of squared errors between market prices and model prices while identifying and removing outliers from the sample. Although the forward rate model is successful at pricing corporate debt, additional factors are found to be significant at explaining the residual price error that remains after the forward rate model is fit to market prices. Six necessary no-arbitrage conditions are derived for the term structures of risky and risk-free debt. Occasionally, some of these no-arbitrage conditions are violated and a few violations are asymptotically statistically significant. Finally, trading strategies that capture mispricing in the corporate debt market and violations of no-arbitrage bounds are discussed.This paper was adapted from my dissertation, completed at Cornell University. An earlier version of this paper was titled The Term Structures of Corporate Debt. Thanks to participants at the Cornell University finance workshop, Warren Bailey, Peter Carr, Antoine Giannetti, and especially Robert Jarrow for their helpful comments.     

会计信息真实性的法律保证

会计信息是经济信息中的重要组成部分，它的真实性决定着宏观和微观经济决策的正确性和准确性，直接影响到国家的经济发展和在国际经济交往中的形象。但长期以来，一些地方政府和企业的领导受利益驱动，提供虚假会计信息，导致会计造假现象十分严重。假数字、假报表充斥着我们经济生活的方方面面，会计打假势在必行。新《会计法》的颁布实施为规范会计行为，净化经济环境，保证会计信息的真实性提供了有力的法律保证。     

MULTIDIMENSIONAL DYNAMIC RISK MEASURE VIA CONDITIONAL g‐EXPECTATION

This paper deals with multidimensional dynamic risk measures induced by conditional g‐expectations. A notion of multidimensional g‐expectation is proposed to provide a multidimensional version of nonlinear expectations. By a technical result on explicit expressions for the comparison theorem, uniqueness theorem, and viability on a rectangle of solutions to multidimensional backward stochastic differential equations, some necessary and sufficient conditions are given for the constancy, monotonicity, positivity, and translatability properties of multidimensional conditional g‐expectations and multidimensional dynamic risk measures; we prove that a multidimensional dynamic g‐risk measure is nonincreasingly convex if and only if the generator g satisfies a quasi‐monotone increasingly convex condition. A general dual representation is given for the multidimensional dynamic convex g‐risk measure in which the penalty term is expressed more precisely. It is shown that model uncertainty leads to the convexity of risk measures. As to applications, we show how this multidimensional approach can be applied to measure the insolvency risk of a firm with interacting subsidiaries; optimal risk sharing for ‐tolerant g‐risk measures, and risk contribution for coherent g‐risk measures are investigated. Insurance g‐risk measure and other ways to induce g‐risk measures are also studied at the end of the paper.     

发展无线局域网技术

无线局域网(Wireless Local Area Networks；WLAN)技术是当今无线通信领域最有发展前景的技术之一。WLAN中最新的IEEE802．1lg协议在2003年6月发布，由于它向后兼容IEEE802．11b协议，提供了一种兼容多种操作速率的模式，因而会有良好的发展前景，将成为无线网络的主流标准。     

On the pricing of forward starting options in Heston’s model on stochastic volatility

We consider the problem of pricing European forward starting options in the presence of stochastic volatility. By performing a change of measure using the asset price at the time of strike determination as a numeraire, we derive a closed-form solution within Hestons stochastic volatility framework applying distribution properties of the volatility process. In this paper we develop a new and more suitable formula for pricing forward starting options. This formula allows to cover the smile effects observed in a Black-Scholes environment, in which the extreme exposure of forward starting options to volatility changes is ignored.Received: July 2004, Mathematics Subject Classification (2000): 91B28, 60G44, 60H30, 60E10JEL Classification: G13It is a pleasure to thank the anonymous referee for his valuable comments and suggestions on this paper. Furthermore, we would like to thank Holger Kraft, University of Kaiserslautern, and Alexander Giese, HypoVereinsbank AG Munich, for fruitful discussions and suggestions.     

从“中国原材料出口限制案”看我国应当如何援用GATT1994第20条(g)款

在"原材料出口限制案"中,中国援用GATT1994第20条(g)款抗辩失败。原因有二:一是未能证明贸易限制措施与保护可用尽的自然资源有关;二是未能证明贸易限制措施与限制国内生产或消费一同实施。本文以该案为背景,通过对GATT时期和WTO时期涉及第20条(g)款案件的比较研究,系统梳理了第20条(g)款各项要件的发展脉络,并且透过专家组和上诉机构的审查过程,对每一项要件的举证论证策略加以总结,最终构建出GATT1994第20条(g)款援用方案。     

GATT第20条争端案例下的碳关税征收合法性分析

文章援引GATT第20条豁免条款经典案例,将碳关税合法性纳入WTO争端解决机制"两步走"审核程序。通过剖析争端解决机制对案例的裁决,认为碳关税满足GATT第20条(g)款,同时通过与多边国家协商制定多方认可的碳关税征收的无歧视标准,可通过GATT第20条前言的要求,从而认为碳关税征收满足GATT第20条豁免条款,案例折射出WTO争端解决机制对可耗竭自然资源保护措施的态度由承认其重要性、到肯定再到鼓励,都增加了碳关税征收的可能性。     

明代地方官府赋役核算体系的早期发展

明洪武到弘治年间,州县官府的赋役管理从基本不依赖核算向需要且能够进行核算的状态转变。洪武、永乐时期,在官府体系内部,只有田赋被部分地纳入核算管理,其他赋役征发则完全或绝大部分无法计量,也没有计划性。宣德以降,地方官员吸收民间粮里阶层分担赋役负担的经验,在此基础上进行旨在“均平”的改革,以确保赋役的可持续征发。在探索均平之道的过程中,不同地方官员多采取量化赋役负担、预定征收计划、将派征对象标准化并进行摊派核算的方式。其中,田赋额等开始扮演摊派对象的角色。这开启了州县层面赋役征收核算体系的发展之路,也导致府、州、县与户、工等部及布政使司之间产生了赋役核算信息不对称,出现了二重会计结构。