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6 Standardized Procedures for Personal Travel Surveys It has long been held by most metropolitan regions that data collected in one region has little relevance to another region. While there is no doubt that there will be local contextual issues that may make transfer of data difficult or inappropriate at times, the major reason for this perception is that each household travel survey is usually sufficiently different in design and execution from any other survey, the result of which is that comparisons from region to region are completely obscured by methodological and implementation differences. If consistent procedures were applied in the collection of such data, many of the apparent differences between regions may well disappear. In addition, there are often slight variations in question phrasing that are sufficient to introduce major barriers to comparing data; appropriate standardization could remove these bar- riers. This could also lead to a greater willingness of regions to borrow data from each other, and thus reduce the overall necessity to expend so much on collection of new data. It would also help the recognition and capture of travel among regions and, of particular importance, enable relating local to national surveys. The issue of standardizing personal travel surveys was investigated in this study. This involved reviewing past practice, conducting analyses on data sets collected in past travel surveys, conduct- ing new travel surveys, identifying individual aspects of personal travel surveys that potentially could be standardized, evaluating these candidate procedures, and then compiling a set of recom- mended standardized procedures. The execution of this process is documented in the following pages. Forty procedures in travel surveys are recommended for standardization in this study. An additional 20 were identified for possible standardization but were either considered to be less important than those selected or beyond the scope of the project. Included in the report is a sam- ple Request for Proposals (RFPs) to assist metropolitan areas in commissioning travel surveys that are consistent with the proposed standardization. 1.2 Study Objectives The objectives of this project are to develop recommended travel survey procedures that would lead to an overall increase in the quality and reliability of transportation surveys performed at household and person levels and would also improve the comparability between surveys. These recommendations will provide guidance on how to select cost effective survey methods, how to implement the survey, how to analyze the results, and how to report measures that allow the assess- ment of the quality of the data. By standardizing the travel survey process, comparability of data from place to place and time to time will be enhanced. The reliability of the data will be increased, and doubts as to the applicability of data should be able to be removed. It is also an objective of this research to identify the costs and tradeoffs for the procedures and assessment measures that are identified in this research and to establish whether specific procedures and assessment measures are cost-effective. There can be negatives to standardization: namely, the stifling of innovation or the creation of stagnation in a field. Over the past 30 years, many changes have occurred in the conduct of per- sonal travel surveys, and what constitutes best practice has clearly evolved during this time. If rigid standards had been applied early in this process, this evolution may well have been prevented from occurring. Indeed, imposition of rigid standards at the current stage of development of travel sur- vey procedures would likely retard further development. On the other hand, survey practice has not evolved all that far during this period of open practice, and there are too many instances where surveys are conducted that repetitively perpetrate the same errors. In addition, travel survey pro- fessionals have often remained ignorant of developments and improvements from other fields of survey practice. Standardization might have prevented certain known pitfalls and errors and raised the average quality level of travel surveys. The research team was cognizant of these two aspects of standardization while developing the recommendations included in this research.