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1.
This paper investigates the effect of early school experience on later educational attainment. Using the Indonesia Family Life Survey (IFLS), we find that students who repeat a grade at primary school are less likely to progress to junior high school. We also find that grade retention is associated with lower rates of transition from junior high school to senior high school. The relationship persists across years and samples. Meanwhile, the age of students when starting school and the hours they spend there have limited effects on whether they continue their schooling. We also observe that the effects of parental education and household income on the transition of students from primary school to junior high school are weakening. Given the long-term impact of grade retention, policymakers should be cautious when recommending it for underachieving children and should look for alternatives. 相似文献
2.
Simón Sosvilla-Rivero 《Applied economics》2018,50(42):4540-4555
Expectations are at the centre of modern macroeconomic theory and policymakers. In this article, we examine the predictive ability and the consistency properties of macroeconomic expectations using data of the European Central Bank (ECB) Survey of Professional Forecasters (SPF). In particular, we provide evidence on the properties of forecasts for three key macroeconomic variables: the inflation rate, the growth rate of real gross domestic product and the unemployment rate. 相似文献
3.
西藏江达县白格村金沙江右岸于2018年10月11日和2018年11月3日先后发生2次大规模滑坡—堰塞湖堵江事件,溃堰洪水对下游拉哇库区不良地质体的稳定性造成不同程度的影响。为保障下游水电站建设安全,对拉哇库区主要不良地质体建立了基于星载InSAR技术、无人机技术和地面传感器实时监测的“天空地”一体化监测预警体系,以多维空间采集技术获取变形信息,通过智能监控平台对信息及时进行处理、分析和可视化呈现,利用平台、短信等方式向相关人员进行分级告警,取得了较好的应用效果。 相似文献
4.
Christian Dreger Dieter Gerdesmeier Barbara Roffia 《Bulletin of economic research》2019,71(4):599-615
The analysis of monetary developments has always been a cornerstone of the ECB's monetary analysis and, thus, of its overall monetary policy strategy. In this respect, money demand models provide a framework for explaining monetary developments and assessing price stability over the medium term. It is a well‐documented fact in the literature that, when interest rates are at the zero‐lower bound, the analysis of money stocks become even more important for monetary policy. Therefore, this paper re‐investigates the stability properties of M3 demand in the euro area in the light of the recent economic crisis. A cointegration analysis is performed over the sample period 1983 Q1 and 2015 Q1 and leads to a well‐identified model comprising real money balances, income, the long‐term interest rate and the own rate of M3 holdings. The specification appears to be robust against the Lucas critique of a policy dependent parameter regime, in the sense that no signs of breaks can be found when interest rates reach the zero‐lower bound. Furthermore, deviations of M3 from its equilibrium level do not point to substantial inflation pressure at the end of the sample. Excess liquidity models turn out to outperform the autoregressive benchmark, as they deliver more accurate CPI inflation forecasts, especially at the longer horizons. The inclusion of unconventional monetary policy measures does not contradict these findings. 相似文献
5.
通过百泉泉区天然状态与超采状态下的水环境对比分析,并对岩溶水补给量和开采量进行计算,阐述恢复邢台百泉泉水流量的可行性,随着“引朱济邢”和“南水北调”供水工程的实施,邢台百泉水生态环境的恢复将变为现实。 相似文献
6.
分析了乐滩灌区工程北干渠溯河隧洞段长约1.06 km穿合山煤矿采空区的地质情况.借鉴高速公路煤矿采空区的成功处理经验,通过科学分析,对采空区变形和区域内覆岩的稳定性做了评价,论述了输水线路穿采空区段采取全充填压力注浆法的工程处理方法. 相似文献
7.
8.
介绍了观音阁坝被埋水下6年越冬停浇面水平裂缝采用“粘贴T1密封胶及表面粘三元乙丙后锚固”的处理方案。结果表明,利用胶性材料处理运行中的重力坝迎水面裂缝,技术可靠,方法简单,经济合理。 相似文献
9.
An approach is presented to satisfy the demand for simple criteria, guidelines and models for the preliminary sizing of horizontal subsurface flow (SF) constructed wetland systems. This approach eliminates time-consuming calculations and iterations by providing graphical solutions for wetland system sizing. Therefore, it can be used for the preliminary assessment of new or performance evaluation of existing subsurface flow constructed wetland systems. The validity of this methodology is checked with data from existing systems and is found to be quite satisfactory. This methodology is combined with simple equations predicting the maximum wetland capacity in summer, so as to assist designers in sizing installations in tourist areas with increased summer populations. Furthermore, based on this methodology, a sensitivity analysis is performed of the area requirements for wastewaters of various strengths and various design conditions and performance criteria. The results provide a useful overview to engineers and further simplify the design methodology of new subsurface flow constructed wetland systems. 相似文献
10.
采用宽度平均的立面二维水温模型,通过分析支流和主库之间的相互影响,提出了支流与主库耦合的简化方法,建立了考虑支流影响的水库水温模型。在考虑有无支流影响的条件下,对水库水温分布、水库下泄水温和坝前垂向水温分布均作了比较,结果表明支流对水库水温分布有一定的影响,所建立支流与主库耦合的立面二维水温模型能够较好地反映存在支流影响的水库水温分布,预测水库水温分布比较合理。 相似文献