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61.
Drought and high temperatures are major threats to sustainable food production and consequently the livelihoods of the majority of Africans who depend on fragile agricultural systems. As a response to these threats, climate-smart agricultural technologies, such as drought-tolerant maize (DTM) varieties, have been developed and promoted on the continent. It is well-known that the adoption of improved technologies generally impacts positively on the wellbeing of adopters. Nevertheless, the magnitude of the impact of any technology or intervention is always an empirical question. Therefore, this study sought to determine the factors that influence the adoption of DTM and subsequently estimate how yield, commercialization intensity, and farm income are affected by adoption. To establish causation, we relied on observations from 200 farm households in the Northern Region of Ghana and estimated an instrumental variable regression. Consistent with findings reported in the literature, we found that DTM adoption is primarily driven by access to seed, extension service, labor availability, and location of farm households. In addition, we found that DTM adoption positively impacts on yield and commercialization intensity. The magnitude of impact is not trivial. For example, the yield of farm households increased by more than 150% (936 kg/ha) following DTM adoption. These results imply that policy-makers and development practitioners must support research and promotion of climate-smart agriculture to improve adoption and welfare indicators, such as yield and commercialization.  相似文献   
62.
This article estimates agglomeration effects via calculating EG (Elilsion & Glaeser) and TFP growth (Total Factor Production) by considering the undesired output of the industrial enterprise database and the entropy weight method. Using panel data of 207 county-level cities in China and 28 two-digit manufacturing industries from 2003 to 2013 based on SIC codes, this paper analyzes the relationship between agglomeration and TFP growth through the smooth transition model under different regions and factor-intensity. The results are as follows. (1) A negative relationship appears in manufacturing productivity. The agglomeration effect changes to the crowded effect. Environmental pollution is also generated by transportation and inadequate pollution treatment technology. (2) The excessive agglomeration phenomenon of developed areas (eastern region) is less than the less developed areas (central and western regions). (3) Resource-intensity industries present two thresholds that indicate complex regional features. For various intensive industries in different regions, the relationship between GML and agglomeration is different. High agglomeration does not always promote TFP growth. (4) At different levels of urban industrial agglomeration, the influences of efficiency change and technical change on GML are different. Overall, moderate agglomeration in all regions helps promote economic development.  相似文献   
63.
Female labour force participation rates across the Middle East and North Africa (MENA) region have remained low for over four decades even though, in the same period, women's education rapidly increased and fertility rates substantially decreased. This study provides a better understanding of this surprising phenomenon by testing whether the number of children affects the mother's labour supply (using twins at first birth as an instrumental variable.) Despite a strong first stage, it does not find statistically significant effects in the second stage, even in the combined sample of over 100,000 observations. This non‐result, however, does not rule out that fertility affects women's employment in these countries. But it rejects impacts larger than 0.09. Similar twin‐studies in the United States found effects between 0.12 and 0.31. The paper discusses the implications of this result in understanding the puzzle of female participation in MENA and in designing policies to increase women's employment.  相似文献   
64.
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。  相似文献   
65.
This paper estimates the causal effect of fiscal rules on fiscal balances in a panel of 142 countries over the period 1985–2015. Our instrumental variable strategy exploits the geographical diffusion of fiscal rules across countries. The intuition is that reforms in neighboring countries may affect the adoption of domestic reforms through peer pressure and imitational effects. We find that the mere existence of fiscal rules correlates with lower deficits, but the positive link disappears when endogeneity is correctly addressed. However, when considering the strength of rules through a continuous index of fiscal rules’ design, we show that well-designed rules have a statistically significant impact on fiscal balances. We conduct several robustness tests and show that our results are generally robust and not affected by weak instrument problems.  相似文献   
66.
In this paper we compare conceptualising single factor technical and allocative efficiency as indicators of a single latent variable, or as separate observed variables. In the former case, the impacts on both efficiency types are analysed by means of structural equation modeling (SEM), in the latter by seemingly unrelated regression (SUR). We compare estimation results of the two approaches based on a dataset on single factor irrigation water use efficiency obtained from a survey of 360 farmers in the Guanzhong Plain, China. The main methodological findings are that SEM allows identification of the most important dimension of irrigation water efficiency (technical efficiency) via comparison of their factor scores and reliability. Moreover, it reduces multicollinearity and attenuation bias. It thus is preferable to SUR. The SEM estimates show that perception of water scarcity is the most important positive determinant of both types of efficiency, followed by irrigation infrastructure, income and water price. Furthermore, there is a strong negative reverse effect from efficiency on perception.  相似文献   
67.
王秋洋 《价值工程》2015,34(8):240-241
本文以现有财务管理、财务预警系统理论和实践研究为基础,从筹资风险、投资风险、经营风险和收益分配风险四个方面建立财务风险预警指标体系,最后通过使用层次分析法、综合功效系数法等技术,设计了一套初级的企业财务风险预警模型。本文以我国深市所有石油上市公司为研究样本,有一定的实际价值。  相似文献   
68.
Demand projections for civil aviation have forecast increases in operations in future decades. Increases in demand are beneficial to the growth and advancement of the aviation industry, but also come with the threat of significant increase in environmental impacts. In response, the industry is focusing on programs to develop technologies for reductions in fuel burn, NOx emissions, and noise. While aircraft-level impacts are an obvious metric of success, it is difficult to make informed robust technology investment decisions with respect to noise without understanding the fleet-level impacts. Fleet-level predictions of noise for technology explorations are especially complicated because it is computationally expensive, highly combinatorial, and airport-specific. Recently, rapid automated airport noise models have been developed, which can be simulated using Design of Experiments (DOE). The results of these simulations are used to generate surrogate models for airport noise contour area, which can be summed to yield a fleet-level impact. These models make use of simplifying assumptions to provide estimates of airport-level noise that are substantially cheaper to compute. They can be used to perform parametric trade-off analyses in conjunction with the equivalency assumption. Equivalency asserts that environmental impacts of a technology infused aircraft can be represented by scaled operations of the baseline aircraft in the same class. This simple assumption allows for the modeling of technology and market penetration factors under the same units: operations. This research uses surrogate models in conjunction with the equivalency assumption to examine two potential technology scenarios in a target forecast year, simulating technology and market performance factors to identify vehicle classes that could have the greatest impact in reducing contour area. Results show that technology and market performance of future notional Small Single Aisle and Large Single Aisle vehicle aircraft have the highest positive correlations with potential reductions in contour area.  相似文献   
69.
全面剖析了1953—2014年中国政府科技投入的规模和强度的变化态势,系统分析了政府科技投入与经济增长的弹性系数的变化情况。通过回归分析和协整检验,分析了1953—2014年中国政府的科技投入与经济增长的相关性。结果表明:1953—2014年中国政府科技投入的规模和强度不断加大,政府科技投入对经济增长的平均贡献率达到13.2%;政府科技投入与GDP增长之间存在较强的正相关关系和长期动态均衡关系。指出:为实施创新驱动发展战略、实现建设创新型国家的宏伟目标,应稳定增加政府科技投入、优化科技投入结构、完善和创新科技投入管理体制机制。  相似文献   
70.
This paper first sets up a firm heterogeneity trade model and shows that given capital stock and productivity, export firms will have higher rates of capacity utilization. In addition, given capital stock and fixed export costs, firms with higher productivity are more likely to export. I then use the 2012 Chinese enterprise survey from the World Bank to empirically investigate the impact of participation in export on Chinese firms’ capacity utilization rate. The results show that on average, export firms have capacity utilization rate 1.55–2.01 percent higher than non-export firms, which amounts to 14.6–18.9 percent of the standard deviation of capacity utilization rate in the sample. I also find that firms with a larger part of shares owned by the government have lower capacity utilization. Stronger market competition leads to over-investment and therefore lower capacity utilization rate. Faced with more rigorous labor market regulation, firms will substitute capital for the use of labor, resulting in higher capacity utilization rate.  相似文献   
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