非农就业对种植决策的影响*——基于土地地势的研究视角

［目的］农村劳动力非农转移影响农户农业生产方式变迁，土地质量差异造成的生产差异会随着农村劳动力非农转移造成的人力投入减少而更加显现。针对农户的市场经济行为，文章从理论及实证角度探讨农户农业劳动投入减少时农户生产决策的变化，并根据实证结果进一步探讨我国农业种植结构的变化趋势，为相关政策的制定提供决策参考。［方法］该文运用多元回归模型，从土地资源异质性的视角分析了劳动力非农就业后在不同地势耕地的农业生产决策变化。［结果］劳动力非农就业明显影响了农户种植决策，在质量较高的平地上，农户的生产决策是种植机械化生产使用高的粮食作物来减少劳动力投入下降，在质量较差的山坡地上，农户的生产决策是降低对山坡地的使用强度来解决劳动力投入不足问题，具体表现方式是降低粮食种植面积以及抛荒方式来分配家庭农业劳动投入。［结论］不同地势耕地利用强度将会出现不同变化，平原以及交通便利地区，可以通过机械来替代人力投入，交通较为不发达的山区丘陵地区，需要通过加大农业基础设施建设等来解决山区丘陵地区的抛荒问题。政策支持方面，鼓励中低产田提高产品产量与提升降本技术，保障与维护国家粮食安全。     

Inference for large financial systems

We treat the parameter estimation problem for mean‐field models of large interacting financial systems such as the banking system and a pool of assets held by an institution or backing a security. We develop an asymptotic inference approach that addresses the scale and complexity of such systems. Harnessing the weak convergence results developed for mean‐field financial systems in the literature, we construct an approximate likelihood for large systems. The approximate likelihood has a conditionally Gaussian structure, enabling us to design an efficient numerical method for its evaluation. We provide a representation of the corresponding approximate estimator in terms of a weighted least‐squares estimator, and use it to analyze the large‐system and large‐sample behavior of the estimator. Numerical results for a mean‐field model of systemic financial risk highlight the efficiency and accuracy of our estimator.     

审计质量、产权性质对上市公司投资效率的影响研究

审计质量作为第三方会计师事务所为公司提供的服务,可以独立于公司之外对上市公司投资活动进行监督。根据产权理论,产权性质不同的经济组织从事的经济活动不同,审计质量对不同产权性质的上市公司投资效率的影响也不相同。本文以2014—2018年沪深两市上市公司作为样本,实证检验了审计质量、产权性质与公司投资效率间的关系。研究发现,审计质量与上市公司投资过度显著负相关,与投资不足负相关但作用并不明显;在国有上市公司中审计质量对投资过度行为的抑制作用更明显,在非国有上市公司中审计质量可以在一定程度上防止投资不足行为的发生但作用并不显著。研究结论有利于启示各不同产权性质公司的利益相关方,客观认识审计师的作用功能及其局限性,有针对性、有效率地利用好审计服务,改善公司投资效率。     

京津冀城市群能源代谢时空特征及优化调控研究

随着中国经济的快速发展,能源消费也快速增长。随着节能减排的压力越来越大,能源的代谢需要根据需求进行更替。论文就京津冀城市群能源代谢时空特征分析并对能量代谢进行优化和调控提出建议。     

A quantitative study of financing efficiency of low‐carbon companies: A three‐stage data envelopment analysis

This study set out to evaluate the financing efficiency of low‐carbon companies. Applying a three‐stage data envelopment analysis with the data from 85 listed companies in China's low‐carbon industries over the period 2011 to 2017, this study has found that the overall financing efficiency of low‐carbon companies was relatively high, and the pure technical efficiency was quite steady over the period. The overall financing efficiency of these low‐carbon companies on average tended to change with the scale efficiency. This study has also shown that the scale efficiency was the main constraint influencing the financing efficiency of low‐carbon companies in China over the period. Our results are robust and have significant implications for policy makers and corporate managers.     

水足迹视角下三江平原地区农业水土资源配置效率研究

[目的]三江平原地区是我国重要的商品粮基地,其农业水土资源相对丰富但水土资源配置效率不佳,亟待改善。[方法]运用投入导向型数据包络分析(DEA)方法,对水足迹视角下的三江平原地区农业水土资源配置效率进行评价。[结果]2015年,三江平原地区农业水土资源配置综合有效的地区仅占5%,总体来看,农业水土资源配置的技术效率略好于规模效率;水土资源投入冗余状况分析表明,友谊县、虎林市、宝清县、汤原县、富锦市、同江市等8个县、市辖区的农业水土资源投入合理,其他地区都存在不同程度的冗余现象;分作物来看,水稻生产的水土资源配置技术效率高于其他三大旱作。[结论]完善农业基础设施配套工程,提高水土资源配置的技术效率,是提高其规模效率,进而实现综合有效的关键。     

What determines the efficiency of Australian mining companies?

We examine the firm‐specific determinants of technical efficiency in Australian mining companies using data envelopment analysis (DEA). To do so, we employ panel data sourced from individual mining companies listed on the Australian Securities Exchange (ASX) over the period 2010–2014. To ensure valid statistical inference in the presence of serial correlation between DEA efficiency scores, we apply Simar and Wilson's two‐stage bootstrap method. We find that ownership concentration, firm size, firm age, product portfolio, product diversification and growth status significantly contribute to efficiency gains. However, other firm‐specific factors, such as capacity utilisation, financial risk and overseas operations appear to have limited impact on the technical efficiency of mining firms.     

SHIRKING,STANDARDS AND THE PROBABILITY OF DETECTION

By relaxing the common efficiency wage assumption of exogenous shirking detection probabilities, we demonstrate how standards and efficiency wages are related. In a more general setting where the probability of detection depends upon the equilibrium effort level of non‐shirkers, we show that the uniformly positive (negative) supply‐side relationship between wages (unemployment insurance) and effort is no longer guaranteed. Profit maximization on the part of the firm, however, ensures that effort will depend positively (negatively) on wages (unemployment insurance) in equilibrium.     

敦煌种业财务绩效评价研究

选择以农业上市公司敦煌种业为研究对象,以企业2014—2019年的报表数据为基础,采用功效系数法并以国务院国资委所编写的《企业绩效评价标准值》中国有企业绩效评价体系作为参考,构建对农业企业的财务指标评价体系,对敦煌种业2014-2019年企业财务指标的表现进行纵向分析,选择同行业中营业收入水平较高的北大荒进行横向对比,通过对比发现敦煌种业的问题主要体现在盈利能力和资产质量方面,对此提出了改进措施及建议。     

The rebound effect on energy efficiency improvements in China’s transportation sector: A CGE analysis

Energy use is becoming more efficient due to technological innovations. We focused on the transportation sector in China to develop a national multisector computable general equilibrium (CGE) model for analyzing the rebound effect from an improvement of 10% in the energy efficiency. We compared the size of the energy rebound effect at both the macroeconomic and sectoral levels in different transportation modal subsectors, namely rail, road, water, and air travel. The findings showed that the magnitude of the rebound effect varies across the transportation modes. This is particularly true for the air transportation sector, which has an economy-wide rebound effect of 30.1% and an own-sector rebound effect of 74.6% because of a sharp increase in the export demand for air transport services. We also quantitatively evaluated the contribution of energy efficiency improvement in the transportation sector to China’s economic growth and carbon reductions and found a positive dividend effect on the economy as well as the environment. The modeling results suggest that improving overall transportation energy efficiency by 10% generates an economy-wide welfare gain of approximately 29 billion yuan, while 19 billion yuan are attributable to a more efficient road transportation subsector. Furthermore, to offset the effects of these mode-specific rebound effects, we simulated the effectiveness of different policies and solutions. These included economic instruments in the form of energy, environmental, and carbon taxes, household transport consumption structure adjustments, and energy structure adjustments. This study revealed that combining these sustainable development policies offers opportunities for economy-wide multisectoral improvements in energy savings, emissions reduction, and economic benefits.