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Motor vehicle crashes continue to result in large numbers of fatalities each year and represent the leading cause of death for young persons. In 2006, for example, there were over 42,700 fatalities associated with these crashes. Understanding the causes of these crashes and methods to reduce them continues to be of great interest to economists, public health officials, and policy makers. We present in this paper statistical models using a rich set of panel data covering the period 1980 to 2007 by state and the District of Columbia. Our choice of variables is based on an extensive literature highlighting the importance of policy, safety, demographic, and economic determinants of fatality rates.  相似文献   
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This paper, in two parts, reports on the Perception of Route Competition via Seaports in the European Communities Research Project wherein a total of 72 interviews were held in 11 European countries. Respondents were also asked to fill in a questionnaire, and it is these questionnaire findings that are reported in this first part of the paper. These is a perhaps surprisingly widespread belief that frequency of shipping service is a main reason for choice of seaport in cargo movement. Time on the route and labour problems at ports are major concerns of freight forwarders whose minds are powerfully imbued with the spirit of free enterprise(absence of governmental or other planning agency intervention). Among other major conclusions are a preference for 'delivered price' consignments and the belief in the importance of port charges in route determination (see table 2 for summary of major conclusions).  相似文献   
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Recent years have witnessed a growing volume of papers describing the use of GPS technology and other tracking technologies for obtaining data on time–space activities. These methods have several advantages over traditional methods of time–space data collection in terms of accuracy, resolution and length of the possible data collection period. However, to date, no work has been done on the compliance rates among participants and the resulting validity of the collected data. This paper presents a method that combines the use of a GPS receiver with Radio Frequency Identification (RFID) technology that was implemented in research on time–space activities of elderly persons with cognitive impairment. The method presented in this paper enables monitoring the level of compliance of the participants during their participation in the study and presents a unique opportunity to examine the extent to which participants in a GPS based study are able to comply with study requirements. Healthy older adults and those with cognitive decline were found to be generally compliant with a complex study protocol. These results serve as another step into the acceptance of GPS based studies as a valid methodology for mobility data collection.  相似文献   
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