乌鲁木齐市建设用地对经济增长的贡献及Logistic曲线极限点估计研究

[目的]为提高乌鲁木齐市各生产要素的利用效率,明确经济发展模式,同时也为促进土地资源节约集约利用提供科学依据。[方法]基于C-D生产函数,以2005—2015年乌鲁木齐市统计数据为样本,借助EViews6.0和SPSS20.0软件测算出建设用地对经济增长的贡献率以及Logistic曲线极限点。[结果](1)资本投入要素对经济增长的贡献率(56.72%)最大,建设用地投入要素贡献(32.81%)次之,然后是劳动力投入要素贡献(13.25%),技术进步投入要素贡献(-2.78%)最小,但拥有很大的挖掘空间;(2)建设用地对经济增长的Logistic曲线极限点位于第二、三产业产值为1 522亿元处,对应2011年产值,2005—2011年建设用地对经济增长的贡献呈递增趋势,2011年之后贡献速度呈递减趋势,逐渐趋于平缓。[结论]建设用地对经济增长的驱动作用是有限的,只有通过技术创新才能实现经济发展模式由"依资本型"向"技术驱动型"转变。     

What determines the long-term correlation between oil prices and exchange rates?

In this study, we obtain the long-term correlation between oil prices and exchange rates by employing the dynamic conditional correlation-mixed data sampling (DCC-MIDAS) model. We then identify the factors that influence the long-term correlation using panel data analysis. We find that the long-run correlations between oil prices and exchange rates are negative for all oil-exchange rate markets except Japan. We also find that both inflation and term spread have negative effects, while the risk-free interest rate has a positive effect on the long-term correlation between oil prices and exchange rates. Importantly, the empirical results show that an increase in inflation will significantly damage the real value of the currency itself.     

On credit and output: Is the supply of credit relevant?

The consensus that changes in the supply of credit were irrelevant to making monetary policy decisions existed among macroeconomists during the second half of the twentieth century. Transmission of shocks to the real economy through changes in the supply of credit, however, played an important role in the recent U.S. financial crisis. This paper explores the extent to which policymakers should consider changes in the supply of credit when making forecasts and monetary policy decisions. More specifically, it considers whether a measure of real credit balances offers consistent and stable information, beyond that of a real interest rate and real money balances, about future output gaps during the U.S. post-war era. Results yield evidence that changes in real credit balances are the only variable, among those considered, to provide consistent and stable information about future output gaps over the entire sample period. Each information variable, however, provides relatively little value added for forecasting future output gaps, beyond a simple autoregressive model. To improve upon forecasts and monetary policy decisions, policymakers therefore should consider a broader range of information variables and occasionally reassess the relative weightings assigned to each.     

成渝经济区生态农业对区域经济影响分析

[目的]区域经济发展反映经济各个方面的综合发展状况,探讨其影响因素以确定区域未来经济的发展方向,为进一步规划发展提供科学依据。[方法]先构建生态农业评价指标体系再采用层析分析法确定权重,结合线性加权和函数计算生态农业评价指数,通过相关分析法分析生态农业各个指标与区域经济的关系,最终确定生态农业对成渝经济区经济的影响程度。[结果]生态农业指标中评价指数大于0.9是森林覆盖率,介于0.8~0.7的包括投入产出比、土地生产率、农业科技贡献率、万人拥有的科技人员、劳动生产率、化肥施用量。且生态农业中各个指标与GDP都正相关,其中森林覆盖率、人均收入增长率、农业科技贡献率和万人拥有的科技人员与GDP显著相关,对区域经济的影响最大。[结论]成渝经济区经济受生态农业的影响,进一步选取更多生态农业相关因素,对于全面促进区域经济持续发展具有十分的重要现实意义。     

农户减少化肥用量和采用有机肥的意愿研究——基于洱海流域上游面源污染防控的视角

[目的]过量施用化肥导致水体富营养化是造成洱海流域上游面源污染的主要原因之一,调查分析农户减少化肥用量和采用有机肥的意愿有助于了解其调整施肥结构的行为。当前研究忽视了农户减少化肥施用强度和采用有机肥的意愿间的替代性,未能开展联立研究。[方法]基于洱海流域上游397个水稻种植户的问卷调查数据,通过Bivariate-Probit模型对农户减少化肥用量和采用有机肥两种意愿进行分析。[结果]年龄负向影响农户减少化肥量的意愿,农户对有机肥好处的认知正向影响其减少化肥量的意愿,农户参加农业社会化服务对其减少化肥用量和采用有机肥的意愿均产生正向影响,相比之下,对农户采用有机肥意愿的促进作用更大。[结论]引导农户参加农业社会化服务以及加强宣传和培训,提高农户对有机肥作用的认知可能是加强其减少化肥用量和增加有机肥施用量意愿的有效途径。     

水源地突发水污染政府应急预留水量需求预测

近年来,随着工业化和产业化的快速发展,水源地突发水污染事件频发。为应对紧急情况下的水资源非常规需求,保障经济社会稳定发展,政府需要安排一部分应急预留水量。如何合理预测政府应急预留水量的规模是一个值得探讨的课题。提出了一种基于案例推理技术的政府应急预留水量需求预测方法,具体思路是:借助于案例库,利用主成分分析法从众多影响水源地突发水污染事件的因素中提取出两两不相关的因子,以此作为案例的特征属性,基于加权曼哈顿距离测算相似度,依此得到匹配案例,进而测算政府应急预留水量。以太湖流域常州地区水源地为例,进行政府预留水量需求量的预测与分析。该方法可以为政府应急预留水量的配置、储备等提供相关理论知识。     

Sources of Productivity Growth Dynamics: Is Japan Suffering From Baumol's Growth Disease?

This study examines the sources of labor productivity growth dynamics in Japan (1970–2010) and investigates the extent to which Japanese economic performance has been affected by Baumol's growth disease (BGD). We find that BGD silently undermines Japanese economic growth. However, the magnitude is miniscule, and consequently the aggregate labor productivity growth rate has not been decreasing monotonically. We also explore how BGD is arising and why it is small in the Japanese economy. BGD is weak because (1) the positive Baumol growth effect is also working in certain services sectors and (2) BGD is not a durable phenomenon: even if a sector begins to suffer from BGD, it is likely to recover quickly.     

Why does the peso-dollar exchange rate show a depreciation trend? The role of productivity differentials

Over the last three decades, Mexico's macroeconomic policy has been driven by a sound orthodox strategy: an open economy via many trade agreements signed since the mid-1980s, a nominal exchange rate under a flexible regime since 1994, central bank autonomy, and responsible fiscal policy, among other benchmarks. Nevertheless, the exchange rate has continued on a path of depreciation against the US dollar. In this paper, we show that although an equilibrium relationship exists between the exchange rate and prices in Mexico and the US (its main commercial partner), there are other forces affecting the former. The main factor in this relentless long-term depreciation is the loss of productivity in Mexico relative to the US. In addition, we show that the extraordinary liquidity supplied by the US during the 2008 crisis caused the Mexican peso to appreciate against the dollar.     

通胀目标制与汇率目标制不能共存吗

基于汇率传递的风险溢价渠道，本文将我国利率调控通胀、外汇储备对冲干预汇率纳入新凯恩斯政策模型，构建双目标双工具政策分析框架，比较泰勒规则与双目标双工具规则下通胀目标与汇率目标共存的经济机制与效应。本文模拟显示：（1）双目标双工具政策框架下通胀目标与汇率目标能够共存，此时通过影响汇率风险溢价来盯住汇率不影响通胀；而单工具政策下两目标无法共存，此时降低国内资产的收益率盯住汇率会刺激居民的消费行为引起通胀。（2）国际资本冲击下，双目标双工具政策在固定汇率的同时能保证经济稳定；而当贸易条件恶化时，选择完全浮动汇率制度最优。央行政策损失分析进一步验证了以上结论。（3）随着金融市场化改革深入，外汇储备稳定汇率的有效性将下降，冲销成本会大幅提升。资本账户开放下，双目标双工具政策仍是央行抵御外部资本冲击的首选政策；但是汇率市场化后，通胀目标制与双目标双工具政策效果基本无差异。本文结论的启示是：面对国际资本，需必要的汇率管制；但是面对贸易冲击，可适度提升汇率弹性来减少冲击对产出和通胀的影响。     

Health screening strategies for international air travelers during an epidemic or pandemic

Air travelers can carry an infectious disease's pathogenic microorganism in their bodies and spread the disease from one country to another in a few days. To delay the spread, health screening stations may be set up at airport terminals to screen travelers. This research tested three different health screening strategies, each with a different combination of screening stations at trip origins, destinations and connecting airports. Discrete event simulations were performed, based on the 2014 to 2016 Ebola virus epidemic, with special focus on travelers from the West African countries traveling to the United States, including travelers who transferred flights at airports in European Union member states. The effectiveness of the screening strategies was analyzed in terms of correct detection, missed detection and false alarm rate. The results showed that exit screening at trip origins brought big improvements in the performance measurements compared to no screening. However, additional screening at the destinations and connecting airports contributed marginal benefits.