Evaluating the long‐term impacts of promoting “green” agriculture in the Amazon

Frontier development in the Brazilian Amazon has created vast areas of largely deforested landscapes. Conservation efforts in these post‐frontier zones seek to protect the remaining forest fragments and promote sustainable agricultural practices that absorb labor, meet market demand, and generate ecosystem services. Assessments of these efforts often find that rates of sustained uptake are disappointingly low and that impacts are difficult to discern, but this could be due to the short‐time frames of both the efforts themselves and their evaluation. We investigate the impacts of participation in an internationally sponsored farmer association that for 15 years promoted sustainable agricultural practices in the heavily deforested state of Rondônia, Brazil. Using data from a georeferenced four‐period panel survey of farmers in combination with remote sensing data on land use spanning the life of the association, we apply matching methods to estimate the impacts of participation. We find that membership resulted in more diversified production systems, including more land allocated to agroforestry. Members also deforested less of their farms, but this difference is not statistically significant after we control for selection bias in membership.     

河南省新密煤田李岗井田煤层与煤质特征分析

通过对新密煤田李冈井田的调查,取样,研究,分析后发现,整个煤层区属于可以采掘区。煤层中灰含量比较低,硫含量低,含有磷,燃烧效率高且无烟。这种煤层符合工业用煤和家用煤炭的标准。     

Post-2010 FIFA Soccer World Cup: oversupply and location of luxury hotel rooms in Cape Town

An excess of hotel rooms in cities preparing to host a mega-event such as the FIFA Soccer World Cup is not a new occurrence. Between 2007 and 2010 the number of five-star hotel rooms in Cape Town increased by 50% and four-star hotel rooms by 20%. A spatial database of three-, four- and five-star hotels was compiled for the hotel sector of Cape Town. This paper reveals the global–local nexus of luxury hotel development in Cape Town (South Africa) and three different contexts in which the oversupply of hotel rooms must be understood. First is South Africa as a developing country engaged in hosting a hallmark event and engrossed in concomitant inflated tourism-related expectations. Second is the vulnerability of Cape Town's hotel sector with its overdependence on long-haul holiday tourists from a narrow northern-hemisphere market experiencing the worst economic recession since the 1930s. Third is the favourable economic trends in South Africa from 1999 to 2007 that have trapped hotel developers in a ‘fallacy of composition’.     

“3+1”培养模式下《金融数学》课程实践教学改革的研究与实践

分析了目前金融数学专业实践教学环节的现状,总结了传统授课形式的不足,结合学校的办学定位及教育理念,提出具有我校特色的"3+1"培养模式的实践教学改革新思路。     

VaR-implied tail-correlation matrices

Empirical evidence suggests that asset returns correlate more strongly in bear markets than conventional correlation estimates imply. We propose a method for determining complete tail-correlation matrices based on Value-at-Risk (VaR) estimates. We demonstrate how to obtain more efficient tail-correlation estimates by use of overidentification strategies and how to guarantee positive semidefiniteness, a property required for valid risk aggregation and Markowitz-type portfolio optimization. An empirical application to a 30-asset universe illustrates the practical applicability and relevance of the approach in portfolio management.     

Empirical likelihood-based inference for the generalized entropy class of inequality measures

We propose an empirical likelihood-based method of inference for comparing inequality between two populations. A series of Monte Carlo experiments are used to assess our method’s finite sample performance. We illustrate our approach using some Canadian household income data.     

Are choice experiments reliable? Evidence from the lab

This study investigates whether a popular stated preference method, the choice experiment (CE), reliably measures individuals’ values for a good. We address this question using an induced value experiment. Our results indicate that CEs fail to elicit payoff maximizing choices. We find little evidence that increasing the salience of the choices or adding monetary incentives increase the proportion of payoff maximizing choices. This questions the increasing use of CE to value non-market goods for policy making.     

青海省物流需求规模预测的实证分析

运用灰色GM（1,1）预测模型,选取货运量为指标,根据统计数据建立了青海省铁路和公路物流需求规模模型,并对青海省十二五期间的物流需求规模进行了预测,在一定程度上能够为青海省物流业发展提供定量依据。     

The transformation of the Indian agricultural input industry: has it increased agricultural R&D?

Indian agricultural input industries have gone through a major transformation in the last 40 years. State owned firms grew during the Green Revolution and then stagnated or declined. Indian corporations that were protected from foreign competition are now exporters of agricultural tractors and pesticides. Foreign multinational corporations are rapidly increasing their role in the seed, pesticide, and tractor industries. Entry by large Indian firms and multinationals has increased competition in the input industries. Private agribusiness R&D in India grew from $23 million in 1985 to $250 million in 2009 in 2005 US dollars. This is the same time period as a transformation in the agricultural input industry, rapid growth in demand for agricultural inputs, breakthroughs in information technology and biotechnology, and changes in intellectual property rights. An econometric model was used to test whether the transformation of agricultural input industry was a major factor in the growth of R&D expenditure or not. This article analyzes a unique, firm level sales and R&D data set from the seed, pesticide, tractor, and fertilizer industries in 2000–2009. The estimated model indicates that agribusiness firms' R&D expenditures from 2000 to 2009 were positively related to variables associated with industry transformation such as firm size, ownership by multinationals, and declining industry concentration. The model also indicates that strengthening patent policy as well as growth in the size of research‐intensive industries like the seed industry contributed to the growth of agribusiness R&D in India.     

Re‐examination of production,cost, and restricted profit functions using quantile regression approach

This article estimates quantile regressions of production, cost, and restricted profit functions using a Cobb‐Douglas functional form with non‐Hicks neutral technology change. In contrast to previous studies, quantile regression estimates reveal the relationship between the independent (production, cost, and restricted profit) and dependent (input quantities and prices) variables at each quantile of the distribution. An empirical application using data from 48 states in United States from 1960 to 2004 indicates the returns to scale and aggregate technology not only differ across production, cost, and restricted profit functions but across states in different quantiles of the distribution. This suggests the traditional measures of returns to scale and aggregate technology are under‐ and overestimated in states at upper and lower quantiles, respectively.