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31.
Reinterpreting the performance of immigrant wages from panel data   总被引:1,自引:0,他引:1  
Immigrants differ from the native born in terms of unobserved factors, such as motivation, and observed factors, including those related to the interruption of labour market activity and earning capacity, which may bias estimates of immigrant integration. Using panel data from the Survey of Labour and Income Dynamics, we show that using potential experience, rather than actual experience, exaggerates estimates of the disruption and recovery caused by immigration. More importantly, we find support for omitted variables bias, arising from unobserved fixed effects. Instrumental variable estimates for both pooled and separate samples of immigrant and native born men demonstrate a wage disadvantage for immigrants upon entry that persists through their lifetime. Standard estimates of a modest wage advantage for the children of immigrants also suffer from omitted variables bias arising from unobservables. Contrary to most of the literature to date, our instrumental variable estimates which allow for unobservable fixed effects suggest that immigrants never catch up to otherwise comparable native born workers, but their children do just as well. We would like to thank Statistics Canada for permitting access to the data and solving associated technical problems, the Prairier Centre for Research on Immigration and Integration for financial assistance, and Peter Schnabl for excellent research assistance. An earlier version of this paper was presented to the 10th International Conference on Panel Data in Berlin, July 5–6, 2002. The authors take sole responsibility for errors, omissions and interpretation of the data.  相似文献   
32.
In this article, we demonstrate by simulations that rich imputation models for incomplete longitudinal datasets produce more calibrated estimates in terms of reduced bias and higher coverage rates without duly deflating the efficiency. We argue that the use of supplementary variables that are thought to be potential causes or correlates of missingness or outcomes in the imputation process may lead to better inferential results in comparison to simpler imputation models. The liberal use of these variables is recommended as opposed to the conservative strategy.  相似文献   
33.
面向电子商务的现代物流管理信息系统的开发   总被引:2,自引:0,他引:2  
罗云 《物流技术》2002,(12):29-30
结合现代物流技术发展趋势,分析探讨了面向电子商务的现代物流管理信息系统的开发技术路线,关键技术内容,功能体系结构设计及分层逻辑模型设计。  相似文献   
34.
企业信息化建设的重要性已逐渐被企业家所认识。根据油田集输企业的特点 ,论述了这类企业进行信息化建设的特殊意义 ,提出了信息化建设的发展战略及具体内容 ,为建设“数字集输”提供思路和方法。  相似文献   
35.
本文利用深市基金指数高频数据,采用Anderson和Bollerslev(1997)提出的弹性傅立叶回归(FlexibleFourierFormregression,即FFF回归)方法首次对深市基金市场进行了日内周期性的研究。通过对高频收益的定性分析,发现基金市场具有同股票市场相似的周期性,并对这一周期性进行了初步的理论解释。通过FFF方法,将该周期因子进行滤波处理以后,基金指数高频绝对收益不再具有明显周期性。FFF回归能较好地确定日内周期因子。  相似文献   
36.
利用我国1999-2002年省际区域的面板数据,运用面板数据Granger因果关系检验技术,对我国市场化水平与经济增长的关联度进行了实证分析.得出市场化是经济增长的Granger原因,但是经济增长不是市场化的Granger原因的结论.  相似文献   
37.
ABSTRACT

In this paper a novel information model that can be used in Manufacturing Execution Systems is presented. The model is based on the fusion of ISA95, AML and OPC UA. ISA95 is used to define, unify and describe the details of a product and production technology. It also enables communication with ERP systems. The AML standard allows information about the production facilities to be presented. The OPC UA address space represents different parts of an information model while the OPC communication protocol enables it to be linked to actual production systems. The proposed concept is illustrated using an actual example of a production line for electronic devices.  相似文献   
38.
黄贝 《企业技术开发》2007,26(9):30-32,43
湘潭钢铁集团第二高线厂的高线生产是公司生产的重要环节,保证高线设备的稳定运行对于整个高线生产有着重要意义。高线设备采用在线状态监测系统对机械设备运行状态进行实时振动监测和故障分析,从而可以获得机械设备的实时运行状态数据,对设备运行状况及发展趋势做出科学评价,并对一些重要参数实现超限报警。  相似文献   
39.
The purpose of this paper is to explain the pattern of regional unemployment in transitional China. A model is developed to explore how urban unemployment in the provinces is influenced by peasants' wages, formal sector wages, and the size of the formal sector. Evidence from panel data suggests that a significant indicator of high unemployment rates is greater Urban–Rural Income Inequality within the province. The hypothesis is that the urban–rural income gap produces migration, and more rural migrants substitute for urban workers, causing further urban unemployment.Since the economic reforms began in 1978, the non-state owned enterprises have been carrying an increasing weight in the economy, and they have contributed significantly to the rapid economic growth of China. Empirical evidence shows that economic reforms have reduced unemployment. The provinces that are still heavily dependent on the state sector are therefore more likely to experience higher unemployment.  相似文献   
40.
Slack-adjusted efficiency measures and ranking of efficient units   总被引:1,自引:4,他引:1  
In non-parametric methods many units are calculated as efficient. The article suggests a method for ranking efficient units, not by their efficiency, but by importance as benchmarks for the inefficient units, in contrast to earlier suggestions in the literature which rank units high if they are specialized. However, the total potentials for improvement frequently remain unrevealed by calculating radial efficiency measures of the Farrell type only. The article therefore first develops efficiency measures that explicitly extend the radial measures to include slacks. The new measures are applied to a typical multidimensional small-sample data set for Norwegian employment offices.  相似文献   
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