村级尺度耕地产能空间分异及其影响因子分析

[目的]通过探究耕地产能空间分异规律与影响因子,识别地区粮食生产关键制约因素,提升高标准基本农田建设的针对性和建设效果。[方法]采用空间自相关模型刻画了村级尺度耕地产能空间分异规律,对比分析了线性回归模型和地理加权回归模型在耕地产能影响因子识别的效果,并依此划分产能提升类型区。[结果](1)海伦市耕地产能呈现中西部高北部偏低的态势,且具有较强的空间自相关特征。(2)海伦市耕地产能与黑土层厚度、出现障碍层深度、耕作距离、田块状况和质地等变量显著相关,且均呈正相关,但在空间上表现出不同程度的异质性。(3)基于地理加权回归模型的耕地产能影响因子,提出了产能保持区、耕作条件改良区、质地改良区、障碍层改良区和保护性耕作区5类耕地产能提升类型区。[结论]文章所采用的基于村级尺度耕地产能及其空间分异因素模型相关研究,能够较好揭示村级耕地产能空间分布特点、空间自相关性特征及影响因子分布特征,基于此所划分的耕地产能提升类型区较已有研究对耕地分类管理具有更精准的支撑作用。     

State dependence in access to credit

This paper investigates whether firms’ access to credit is characterized by state dependence. We introduce a first-order Markov model of credit restriction with sample selection that makes it possible to identify state dependence in presence of unobserved heterogeneity. The results, based on a representative sample of Italian firms, show that state dependence in access to credit is a statistically and economically significant phenomenon and that this is more prominent among medium-large firms.     

Does corporate governance still affect firm performance after controlling the distress factor?

We explore the impact of corporate governance on firm performance. We first identify whether corporate governance can still be an influential factor or has been largely captured by the traditional Fama-French three-factor model. More importantly, our study adds a financial distress factor to the Fama-French three-factor model to form a four-factor pricing model (labelled as the ‘financial distress four-factor model’). We find that for the US Russell 1000 firms, the financial distress four-factor model is the better model of the two models considered. We further find that the financial distress four-factor model has a higher explanatory power in capturing the return variation. We find that the differences between the return of firms with good (weak) corporate governance and the expected return are insignificantly different from zero for most portfolios in all the two models. The financial distress four-factor model, however, has the fewer portfolios with return difference being significantly different from zero, implying that corporate governance has been better priced in the financial distress factor.     

Linking sustainable business models and supply chains — Toward an integrated value creation framework

Extant literature on sustainable business models highlights that value creation stems from resources exchanged in relationships between a focal firm and its stakeholders. In this context, the literature has, so far, focused on direct relationships. However, despite the acknowledged relevance of sustainability issues in supply chains, this relational view of the focal company and its direct stakeholders has not been extended toward value creation for and with indirect stakeholders, such as stakeholders of suppliers. Addressing this gap, this conceptual article integrates a relational view of sustainable supply chain management into the management of sustainable business models. It extends the scope of sustainable business models from relationships between the focal firm and its direct stakeholders to indirect relationships with stakeholders of suppliers. A framework is developed that supports analysis and management of value-creating relationships between the focal firm, suppliers, and stakeholders of suppliers. By extending the conceptualization of sustainable business models to consider relationship chains beyond direct relationships, this article proposes that a focal firm has to actively manage interactions both with suppliers and with suppliers' stakeholders.     

Guarantees,transparency and the interdependency between sovereign and bank default risk

Bank debt guarantees have traditionally been viewed as costless measures to prevent bank runs. However, as recent experiences in some European countries have demonstrated, guarantees may link the coordination problems of bank and sovereign creditors and induce a functional interdependence between the likelihoods of a government default and bank illiquidity. Employing a global-game approach, we model this link, showing the existence and uniqueness of the joint equilibrium and derive its comparative statics properties. In equilibrium, the guarantee reduces the probability of a bank run, while it increases the probability of a sovereign default. The latter erodes the guarantee’s credibility and thus its effectiveness ex ante. By setting the guarantee optimally, the government balances these two effects in order to minimize expected costs of crises. Our results show that the optimal guarantee has clear-cut welfare gains which are enhanced through policies that promote greater balance sheet transparency.     

现代图书馆人本管理的运行机制

本文结合在现代图书馆的管理过程中出现的一些问题,阐述了"物本"管理模式的主要形式和存在的弊端和引进"人本"管理模式的优势,分析了引进人本管理的必要性和紧迫性,探讨了"人本"管理模式的整体运行机制。     

Living on the edge: Household vulnerability to food-insecurity in the Punjab,Pakistan

This study investigates the prevalence, sources and distribution of household vulnerability to food-insecurity in the Punjab, Pakistan. Applying a multilevel model on a large dataset of about 90,000 households, we find that the share of households at risk of becoming food-insecure (vulnerability) is higher than the share that is current food-insecure. Households in rural areas are least vulnerable. In contrast, residents of cities and urban areas experience high level of vulnerability that exceeds the average in the Punjab. The risk-induced vulnerability is higher than the structural-induced vulnerability and vulnerability to idiosyncratic shock is higher than vulnerability to covariate shocks. Findings imply that households in the Punjab are vulnerable not as a result of poor resource endowments but because of risk. The Pakistani government should go beyond mere observed food-insecurity to address the needs of the relatively larger population that is at risk of being food-insecure in the future.     

Oil commodity returns and macroeconomic factors: A time-varying approach

This paper analyses the dynamic influence of macroeconomic factors on oil commodity returns (crude oil and heating oil) shown in monthly data over the period of 1990–2013. Using a time-varying parameter model via the Kalman filter, we find that macroeconomic factors are relevant for explaining oil commodity returns. We find that multilateral exchange rates have a negative effect on commodity returns. We confirm the existence of a strong linkage between energy and non-energy commodities. More importantly, we find shifts in global demand and SP500 effects that are not identified through the constant parameter model. These variables have had a progressively positive effect on oil commodity returns, especially since 2008.     

基于DEA-Tobit模型的马铃薯生产效率分析——以甘肃省定西市为例

随着社会的进步和农村经济的发展,农业生产效率已成为制约农民收入、造成农村落后的关键因素。中国是马铃薯的生产大国,其生产效率的提高对我国马铃薯产业的持续发展和保障我国的粮食安全有着很重要的意义。研究基于2014年对甘肃省定西市样本农户马铃薯种植的调查数据,采用DEA模型测算农户种植马铃薯的生产效率,并利用Tobit模型对影响马铃薯生产效率的因素进行分析。研究表明:农户生产马铃薯的综合技术效率较低,规模效率成为制约其生产效率提升的瓶颈;家庭纯收入、马铃薯的种植比例和引进新品种3个变量在0.01水平下对生产效率的影响达到显著;户主的年纪在0.05水平下对生产效率的影响达到显著;马铃薯的收购价格、农户是否参加合作社和种植培训、离农贸市场距离与马铃薯的生产效率间存在不显著的正相关关系。基于以上调研提出了鼓励土地流转、提高生产技术水平、加大农民生产技能培训力度、多方面增加农民收入和合理布局农产品贸易市场等政策性建议。     

Is there a virtuous circle relationship between innovation activities and exports? A comparison of food and agricultural firms

This study examines the existence of an interrelationship between innovation decisions and exports for food and agricultural firms as such a relationship could be the source of competitive advantages. Thus, taking as a theoretical basis the focus provided by the Resource-Based-View, the innovation and export decisions taken from 2006 to 2011 by 165 agricultural firms and 783 food companies operating in Spain (Europe) are examined here. The results of the bivariate probit and matching models used indicate a bi-directional nature of these decisions in the case of food companies and a positive though not bidirectional one in the case of the agricultural firms. Furthermore, a certain persistence is seen in the use of these decisions in both types of firms. For food companies, capital intensity and size are also determinants of innovation and exports. From the viewpoint of the decisions taken by individual firms, the bidirectional relationship could involve significant pressure in terms of the larger volume of both technological and human resources required. Agricultural and food policy decisions should incentivize these decisions given that in order to operate successfully in the global market it is necessary to acquire these competitive advantages, which also favor the growth of the agriculture and food trades.