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171.
Summary Chronic daily cannabis use has been shown to have long term harmful health effects, which in turn is expected to reduce labour market productivity. The evidence is less clear on the health impact of less frequent consumption, which is the more typical mode of use, and previous empirical studies fail to find robust evidence of an adverse impact of these modes of use on labour market productivity. This paper attempts to shed some light on this issue by directly estimating the impact of cannabis consumption in the past week and past year on health status using information on prime age individuals living in Australia. We find that cannabis use does reduce self-assessed health status, with the effect of weekly use being of a similar magnitude as smoking cigarettes daily. Moreover, we find evidence of a dose-response relationship in the health impact of cannabis use, with annual use having roughly half the impact of weekly use.Helpful comments on an earlier draft were received from Jan van Ours, Rosalie Pacula, two anonymous referees and participants at the 81st Annual Conference of the Western Economic Association International.  相似文献   
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In response to real and perceived abuse by market makers, buyers, and sellers, some industry trade groups representing suppliers have developed voluntary codes of conduct, white papers, and other forms of guidance for online reverse auction participants. The intent of these guidelines is to improve both the reverse auction process and relationships between buyers and sellers. This paper examines the rationale for creating guidelines and codes of conduct, and examines their efficacy in regulating reverse auctions to achieve improved outcomes for market makers, buyers, and sellers. Data from primary and related secondary sources indicate that industry-specific codes of conduct and guidelines have not had a favorable impact.  相似文献   
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赵丽  吕莹 《特区经济》2005,(11):220-221
当今世界,人才资源已成为最重要的战略资源,人才不仅在国际竞争中越来越具有决定性意义,而且在国内竞争中也发挥着愈来愈重要的作用。从某种意义上讲,区域经济的竞争实际上就是人才的竞争。一个地区经济越发达,集聚的人才也就越多,而人才集聚得越多,也就越能促进当地发展。改革  相似文献   
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Operational Research and the environment   总被引:1,自引:1,他引:0  
The discipline of Operational Research (OR) is primarily concerned with improving the effectiveness and efficiency of decision processes. These processes take place everywhere in society: industry, banking, agriculture, government, politics. Frequent use of mathematical optimization models is typical of OR. Since the early '80s these models are increasingly packaged in a user-friendly way, as Decision Support Systems. In the following we will illustrate how OR can be used to describe and solve a number of environmental problems.  相似文献   
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To examine the relationship between participation in a wellness program and the amount of absenteeism and medical claims, seven years of retrospective absenteeism and medical claims records were collected for 207 employees (pre- and postwellness intervention) and entered into a database. A proportional stratified random sample of workers by wellness participation was selected. While there was no significant change in the amount of sick leave taken over time, a log transformation revealed a significant increase in the dollar amount of medical claims over time, particularly for the middle-aged group of employees. This confirms that wellness intervention slowed the rate of increasing claims among middle-aged participants after just three years of wellness intervention.  相似文献   
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