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101.
This paper proposes a new framework based on the combination of the dynamic DEA, meta-frontier analysis theory, and truncated regression model, and then focuses on the efficiency evaluation of regional high-tech industries in China. For all of the overall technical efficiency, technical efficiency, and scale efficiency scores, the east area is always in the lead, with the central and west areas obviously lagging behind. The eastern area has the highest technology level, whereas the west and central areas fall behind in turn. However, the meta-technology ratio of the west area has rapidly increased and presents a trend of catching up with the east. The variables of GRP per capital, total exports and imports, highway mileage per capita, and ratio of tertiary industry to GRP have positive relationships with technical efficiency, and the time trend exhibits a negative coefficient.  相似文献   
102.
Over the past centuries, land systems in Italy experienced fundamental shifts, owing to the availability of new energy forms, population surges, and technological progress. The 20th century was characterized by massive productivity increases, accompanied by gradual land abandonment and the return of forest land. We here analyze 120 years of land system change in Italy, applying the human appropriation of net primary production (HANPP) framework, a metric for socio-economic pressures on terrestrial ecosystems. HANPP allows integrating ecological with societal perspectives, by systematically quantifying (a) biomass harvest and (b) the difference between potential productivity of ecosystems and current productivity induced by land use processes, such as land conversion, or land degradation. Besides assessing national trends we calculated HANPP separately for the Italian North and South between 1934 and 2007, in order to scrutinize if high regional discrepancies in terms of natural and socio-economic preconditions translate into diverging land system trajectories. Our results show that national HANPP has been declining from 78% of natural productivity before WWII to 56% in 2007, indicating a declining land -use induced pressure on biomass flows over time. Simultaneously, biomass harvest increased by around 26% due to agricultural intensification, despite shrinking croplands. Although we found a significant difference between the Northern and Southern region in the absolute levels of several land use indicators related to biomass appropriation, the overarching trends of land system change were remarkably similar in both regions. This suggests that underlying drivers of land system change, such as policies aimed at land-use intensification and structural change were equally dominating land system trajectories in the North and South of Italy, not withstanding their socio-ecological divergences.  相似文献   
103.
Recognizing the socio-economic and biophysical causes of land degradation at the national level is important for cause-targeted strategies when designing policies for combating land degradation. This study aims to identify the biophysical and socio-economic factors that significantly affect land degradation across Vietnam and to interpret the causalities underlying the effects. The dependent variables considered in the study are spatial, the extent and intensity of degradation in three land-use zones (agriculture, forest and severely degraded abandonment). The hypothesized explanatory variables are common economic and demographic drivers and bio-physical factors such as soil, terrain constraints, and neighborhood land-use structures that are often neglected in many large-scale land degradation assessments. Instead of using a single inferential statistic technique, we used multi-linear regression and binary logistic regression in a complementary manner to increase the detectability and credibility of the degradation cause analyses. The results showed agricultural production growth had strong and consistent effects on land degradation extent and intensity. Population growth, especially in rural areas, had a strong effect on the extent of overall land degradation. The importance of a neighboring forest was revealed for its ability to reduce land degradation intensity in abandoned, unproductive lands. The concrete faceting of the causal analysis for each land-use zone as social–ecological stratum allowed us to combine the defined social–ecological contexts, contemporary theories, and hypotheses in the field to clarify the causal factors of a complex phenomenon like land degradation. The study demonstrates these contemporary inferential statistics can be complementarily used to sufficiently detect and understand land degradation causes at the national level. The results suggest implications for national land management policy: internalizing land degradation costs in the farming system evaluation for payment for ecosystem services policy, restricting forest conversion, and improving extension services and education in agrarian communities.  相似文献   
104.
死亡率免疫理论及其在长寿风险对冲中的应用   总被引:1,自引:0,他引:1  
基于死亡率免疫理论探讨保险公司长寿风险的自然对冲问题,研究年龄、性别与保险期限等因素与保单久期和凸性之间的关系,发现保险公司欲达到长寿风险的完全对冲,其寿险业务和年金业务必须达到的最小ρ比例应该等于年金和寿险保单的久期之比,表明保险公司可以通过选择调整寿险和年金业务的比例来对冲长寿风险的影响。  相似文献   
105.
Corporate sectors in emerging markets have noticeably increased their reliance on foreign financing, presumably reflecting low global interest rates. The evidence also shows a rebalancing from bank loans towards bonds. To study these developments, we develop a dynamic open economy model where these modes of finance are determined endogenously. The model replicates the stylized facts following a drop in world interest rates; in particular, rebalancing towards bonds occurs because bank credit becomes relatively more expensive, reflecting the scarcity of bank equity. More generally, the model is suitable for studying interactions between modes of finance and the macroeconomy.  相似文献   
106.
Scholars believe that higher social expenditures are usually linked with higher government debts, whereas higher debts reduce social expenditures. However, it is reasonable to speculate that higher government debt may contribute to higher social spending, while fiscal deficits occur during a recession, which commonly creates greater demand for social expenditure. For a deeper investigation, this paper revisits the dynamic relationship between social spending and public debts in the time-frequency domain, using the novel wavelet-coherency analysis as well as the phase-difference technique to derive the co-moved and causal relationships between social spending and public debts in 13 OECD countries. The evidence identifies a dynamic relationship between variables. While higher social expenditures increase government debts, the shocks from government debts to social expenditures are conversely uncertain. We discover that higher government debt does reduce social expenditures, but it may be linked to higher social spending. The robustness of partial coherency and phase-difference discovers the role of a political party in the decision over social welfare programmes in the sample countries.  相似文献   
107.
This study analyses the impact of corruption on government effectiveness for a sample of 130 countries. The findings suggest that less-corrupt countries have better quality of public service, better quality in the formulation and adoption of policies and greater credibility and government's commitment to such policies. The findings also suggest that the effect of corruption on government effectiveness is higher in developed countries. Moreover, the estimates also reveal that countries with the most indebted governments and with higher inflation rates have less-efficient governments, and an increase in rule of law represents a good strategy to improve government effectiveness. In turn, regarding developing countries, the findings show that countries with more democratic regimes have a higher degree of government effectiveness.  相似文献   
108.
中国玉米芯资源量估算及其开发利用   总被引:2,自引:0,他引:2  
文章首先采用文献考证法,确定玉米芯产量与玉米产量之比值;在此基础上,采用副产品比重法,结合玉米产量统计数据,对全国及各省(市、自治区)的玉米芯产量进行估算,并分析其区域分布;通过实地调查,结合文献综述,从原料化、饲料化、基料化、能源化的角度,系统阐述我国玉米芯资源综合利用途径。结果表明:玉米芯产量与玉米产量之比为0.21;2013年全国玉米芯资源总产量为4 590万t,相当于全国秸秆总产量的4.90%或玉米秸秆总产量的19.10%。主要分布于东北地区与黄淮海地区,产量分别为1 586.61万t与1 185.41万t,两地区合计占全国玉米芯产量的60.42%。玉米芯是我国各类秸秆资源中高值化利用率较高的种类,其原料化、基料化、饲料化及能源化利用总量达到800万t左右。食用菌基料化、新型能源化利用是提高我国玉米芯综合利用水平的基本途径。多产品联产可有效地促进我国玉米芯工业原料化利用水平的不断提升。积极开展玉米芯发酵饲料技术推广与应用可为我国玉米芯资源高值化利用开辟新途径。  相似文献   
109.
In 2007, countries in the euro zone periphery were enjoying stable growth, low deficits, and low spreads. Then the financial crisis erupted and pushed them into deep recessions, raising their deficits and debt levels. By 2010, they were facing severe debt problems. Spreads increased and, surprisingly, so did the share of the debt held by domestic creditors. Credit was reallocated from the private sector to the public sector, reducing investment and deepening the recessions even further. To account for these facts, we propose a simple model of sovereign risk in which debt can be traded in secondary markets. The model has two key ingredients: creditor discrimination and crowding-out effects. Creditor discrimination arises because, in turbulent times, sovereign debt offers a higher expected return to domestic creditors than to foreign ones. This provides incentives for domestic purchases of debt. Crowding-out effects arise because private borrowing is limited by financial frictions. This implies that domestic debt purchases displace productive investment. The model shows that these purchases reduce growth and welfare, and may lead to self-fulfilling crises. It also shows how crowding-out effects can be transmitted to other countries in the euro zone, and how they may be addressed by policies at the European level.  相似文献   
110.
We investigate how the level of household indebtedness affects the monetary transmission mechanism in the U.S. economy. Using state‐dependent local projection methods, we find that the effects of monetary policy are less powerful during periods of high household debt. In particular, the impact of monetary policy shocks is smaller on GDP, consumption, residential investment, house prices, and household debt during a high‐debt state. We then build a partial equilibrium model of borrower households with financial constraints to rationalize these facts. The model points to the weakening of the home equity loan channel as a possible reason for the decline in monetary policy effectiveness when initial debt levels are high.  相似文献   
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