政府补贴能否促进高新技术企业的自主创新？——来自中关村的证据

中国政府对高新技术企业投入了大量补贴以激励它们创新,但是对补贴效果的研究并未达成一致结论。基于中关村3万多个高新技术企业2001-2012年的观察值,本文同时采用PSM与DID法对政府补贴的效果进行了研究,结果发现:第一,整体而言,政府补贴显著提高了创新经费支出、新产品销售收入和专利申请数量;第二,进一步将创新细分为自主创新和购买引进新技术之后发现,政府补贴存在“挤出效应”:被补贴企业的自主创新明显下降,而购买引进新技术显著增加;第三,政府补贴对企业的短期创新激励有显著的促进作用,但是对长期创新激励的促进作用不显著。本文对高新技术企业的补贴效果提供了实证绩效评估,所得出的结论有助于政府优化和调整激励创新政策。     

On the importance of the long-term seasonal component in day-ahead electricity price forecasting with NARX neural networks

Daily and weekly seasonalities are always taken into account in day-ahead electricity price forecasting, but the long-term seasonal component has long been believed to add unnecessary complexity, and hence, most studies have ignored it. The recent introduction of the Seasonal Component AutoRegressive (SCAR) modeling framework has changed this viewpoint. However, this framework is based on linear models estimated using ordinary least squares. This paper shows that considering non-linear autoregressive (NARX) neural network-type models with the same inputs as the corresponding SCAR-type models can lead to yet better performances. While individual Seasonal Component Artificial Neural Network (SCANN) models are generally worse than the corresponding SCAR-type structures, we provide empirical evidence that committee machines of SCANN networks can outperform the latter significantly.     

Land system change in Italy from 1884 to 2007: Analysing the North–South divergence on the basis of an integrated indicator framework

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.     

Socio-economic and biophysical determinants of land degradation in Vietnam: An integrated causal analysis at the national level

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.     

Global value chains,large-scale farming,and poverty: Long-term effects in Senegal

This paper presents panel data evidence on the impact of expansion of global value chains and large-scale export-oriented farms in developing countries over almost a decade. We estimate the income effects of wage employment on large-scale farms in the horticultural export sector in Senegal, using data from two survey rounds covering a seven-years period of rapid expansion of the sector. We estimate average income effects as well as heterogeneous income effects, using fixed effects and quantile fixed effects regressions. We find that poverty and inequality reduced much faster in the research area than elsewhere in Senegal. Employment in the horticultural export sector is associated with higher household income and the income effect is strongest for the poorest households. Expansion of the horticultural export sector in Senegal has been particularly pro-poor through creating employment that is accessible and creates substantial income gains for the poorest half of the rural population. These pro-poor employment effects contrast with insights in the literature on increased inequality from rural wage employment.     

The impact of shareholders and creditors rights on IPO performance: An international study

This paper examines the impact of cross-country variation in shareholders' and debt holders' rights on post-IPO performance and survival of newly listed stocks across the globe. Using a sample of 10,490 initial public offerings (IPOs) in 40 countries between 2000 and 2013, we find that post-IPO performance and survival is better in countries with stronger shareholder protection, but the impact of creditor protection is negative i.e. stronger creditor protection leads to poor post-IPO performance and survival. This effect is driven by rules requiring creditors’ consent for company reorganization and the mandatory replacement of incumbent managers. Reputable IPO advisors exacerbate the positive impact of shareholder rights and the negative impact of creditor rights.     

Finite lifetimes,long-term debt and the fiscal limit

The U.S. faces exponentially rising entitlement obligations. I introduce a fiscal limit—a point where higher taxes are no longer a feasible financing mechanism—into a Perpetual Youth model to examine how intergenerational redistributions of wealth, the average duration of government debt, and entitlement reform impact the consequences of explosive government transfers. Three key findings emerge: (1) Growing government transfers cause more severe and more persistent stagflation than in representative agent models that do not capture intergenerational transfers of wealth; (2) A longer average duration of government debt pushes the financing of government liabilities into the future and reduces the short-run impacts of explosive transfers; (3) The time it takes the economy to rebound from a period of growing transfers increases exponentially with the number of years it takes to pass entitlement reform.     

The long-run reversal in the long run: Insights from two centuries of international equity returns

We perform the most comprehensive test of long-term reversal in national equity indices ever done. Having examined data from 71 countries for the years 1830 through 2019, we demonstrate a strong reversal pattern: the past long-term return negatively predicts future performance. The phenomenon is not subsumed by other established cross-sectional return patterns, including the value effect. The long-term reversal is robust to many considerations but highly unstable through time. Finally, our findings support the overreaction explanation of this anomaly.     

The provision of long-term credit and firm growth in developing countries

Do small and young firms benefit from an increase in the provision of long-term loans? By combining firm-level data from 62 countries (over the period 2006–2016) with a new database on short-term and long-term credit provided to the private sector, this article shows a higher provision of long-term credit does not stimulate growth of small and young firms. On the contrary, an increase in the availability of short-term credit spurs firm growth. The main explanation of this (counter-intuitive) result is the differential impact of short-term and long-term credit provision on small and young firms’ access to credit. Young and small firms are able to take advantage of an increase of short-term loans, which allow them to switch from informal finance to bank loans. However, a higher level of long-term credit does not alleviate credit constraints faced by opaque firms because these funds are allocated towards transparent borrowers.     

外国直接投资与中国区域经济发展的实证分析

20世纪90年代以来FDI对中国经济发展影响越来越大。本文利用1991-2003年时间序列和横断面数据,就FDI对中国区域经济发展的短期效应和长期效应进行实证分析。结果表明在这段时间里FDI对中国区域经济非均衡发展有显著的影响,FDI促进中国区域经济发展,但是在区域间的非均衡分布又加剧了区域经济的非均衡发展。最后提出吸引更多的FDI到中西部地区、缩小区域经济差距、促进区域经济均衡发展的政策建议。