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10 TABLE 6 Table 7 summarizes the advantages and disadvantages of ANALYTIC USES FOR ORIGIN self-administered surveys and personal interviews, and the AND DESTINATION DATA types of situations in which transit agencies tend to use one Use Percentage or the other method. Route planning 86 Long-range planning 76 A primary strength of self-administered surveys is that Schedule planning 43 a number of respondents can complete the survey simulta- Modeling 38 Other 24 neously. Survey workers' time can be used efficiently because survey staff can distribute questionnaires to a Total number responding, 21. number of riders as the riders board the bus. Therefore, fewer surveyors are needed to obtain a given number To assess ridership behaviors, attitudes, and usage [Sub- of surveys than with personal interviews. Furthermore, urban Mobility Authority for Regional Transportation a questionnaire can be offered to every rider, avoiding the (SMART) Transit User Survey]. need to sample those boarding a bus or train or passing through a station. Coverage is therefore maximized and Finally, it is not unusual for surveys to have both specific sampling error is minimized. and relatively general purposes. Examples are: Self-administered surveys must be carefully designed so To collect O&D information, including travel purpose that respondents can easily understand the questions, follow information for the regional travel-demand model; to the flow of the questionnaire, and respond accurately. Without obtain a rider demographic profile; and to learn more a trained interviewer to guide respondents through the survey about our ridership needs and travel habits and patterns the importance of good questionnaire design is paramount. to better serve those needs through transit planning (Chapter five discusses design issues.) [Citizens Area Transit (Las Vegas, Nevada) Origin and Destination Survey]. Self-administered surveys also need to avoid or minimize To assess who our customers are and to generate complexities such as skips between questions. Interviewer- input for the passenger estimation model [Metropoli- administered surveys can more readily skip selected questions tan Atlantic Rapid Transit Authority (MARTA) Sys- temwide Survey]. based on answers provided to previous questions. Self- administered surveys are thus most appropriate when the research need is to ask all respondents a uniform set of ques- WHERE AND HOW TO CONDUCT SURVEYS tions. Good examples are simple O&D questions, customer satisfaction, and customer opinion surveys. Central decisions in survey planning involve whether to have riders complete the surveys themselves or to conduct personal The use of self-administered methods can exact a price in interviews, where to conduct the survey (on board or in sta- data quality. Respondents may misunderstand questions, tions), how to distribute and collect questionnaires in the case leading to measurement error. Respondents may also com- of self-administered surveys, and whether to offer any type of plete only a portion of the questionnaire. Survey workers incentives. Each of these issues is discussed in this section. have very limited ability to ensure that respondents complete the questionnaire. Unless asked a question, survey workers Self-Administered or Personal Interviews? cannot usually ensure the accuracy of responses or check the logic or consistency of answers. Transit agencies use self-administered surveys more often than personal interviews. More than two-thirds of the surveys Personal interviews reduce or eliminate problems with reported by transit agencies for this study were entirely or primarily self-administered, whereas only 20% were entirely respondent understanding of questions and with item non- conducted through personal interviews. (The remaining 11% response. Interviewers can also skip questions based on were partially self-administered and partially conducted as previous responses, particularly when using handheld personal interviews.) computers or similar devices. By definition, self-administered surveys involve respon- Personal interviews can generate a very high response rate. dents completing survey forms themselves and then returning Response rates, computed as interviews completed as a per- the forms to the agency. For most of the surveys reported by centage of persons approached, exceeded 80% for surveys con- transit agencies, questionnaires were distributed by survey ducted by MARTA, King County Metro, and Gulf Regional workers dedicated to the task. Other options are to use other Planning Commission (GRPC, Gulfport, Mississippi). employees, such as bus operators, or to make questionnaires available in a convenient location, such as on board the bus, Because they are more time-intensive than self- for riders to pick up. administered surveys, personal interviews tend to be used

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11 TABLE 7 CHARACTERISTICS OF SELF-ADMINISTERED SURVEYS AND PERSONAL INTERVIEWS Self-Administered Personal Interview Strengths Need fewer surveyors to obtain a given Higher level of respondent number of completed surveys because understanding of questions multiple respondents can complete the Ensures that all questions are answered survey simultaneously Obtains responses from persons with Can potentially survey all riders boarding limited literacy skills a bus or train; no need to select a sample from among those boarding Weaknesses Respondents may misinterpret questions Can be time-intensive for surveyors; (measurement error) may need larger number of surveyors Respondents may not complete the entire Possible bias from nonrandom selection questionnaire (item nonresponse) of riders interviewed May result in lower response rate than Cost personal interviews Depends on ability of respondent to read questionnaire Difficult to use branching and skip patterns Situations Projects needing large number of Short questionnaires likely to respondents Need relatively smaller number of be used Same questions asked of all respondents completed surveys Relatively long questionnaires Respondents unable to complete survey due to language, literacy, and/or disability Use as adjunct to self-administration at choice of respondent Implications Survey instrument must be well designed, Length of survey may need to be for survey with clearly worded questions and clear minimized planning navigation Need to interview riders where they will take the time needed to complete the interview when the questionnaire is short and when a relatively small routes with significant Hispanic ridership, conducted some sample size is needed. The King County Transit Ride Free interviews in Spanish. Area survey consisted of a few basic questions about trans- fers, fare payment, and boarding and alighting. The Port PATH interviewers used handheld personal digital assis- Authority Trans Hudson (PATH) (Jersey City, New Jer- tants to record respondents' gender and their answers to the sey) O&D survey was seven questions regarding O&D, seven survey questions. The survey was programmed into access mode, transfers, trip purpose, and trip frequency. the handheld devices for this purpose. Personal interviewing is important when some respon- This was the only survey among those reported by transit dents do not have the literacy or English language skills agencies that used electronic devices for recording respon- necessary to complete a written questionnaire. GRPC offered dents' answers. The use of electronic devices appears not riders a choice of being interviewed or completing the sur- to be widespread for two main reasons. First, they are not vey; most chose to be interviewed, in part owing to language feasible for most self-administered surveys. Second, trials of skill considerations. The Charlotte Area Transit System electronic devices for on-board interviews found that inter- (CATS) also offered the option of either self-administered or viewers had difficulty entering information on a moving bus. interviews; approximately 15% of riders completing the However, according to one company that specializes in this survey asked to be interviewed, primarily persons with area, palm devices have been used successfully for intercept disabilities that made self-completion difficult. A Fort interviews at special events and of recreational visitors. Worth Transportation Authority survey was primarily self- Thus, as the PATH experience illustrates, they may be prac- administered; however, a bilingual surveyor, assigned to bus tical and useful for in-station environments.

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12 On-Board or In-Station Surveying? Station interviewing may also be attractive when the num- ber of stations is relatively small, as with the PATH O&D Closely related to the choice between self-administered sur- survey. Notably, these surveys were conducted as personal veys and personal interviews is the choice between adminis- interviews and were relatively short, so as to minimize the tering the survey on board or in a stationary environment length of the interruption in respondents' trips. (e.g., a rail station or transit center). Seven in 10 on-board/intercept transit surveys are con- Distribution and Collection ducted on board buses or trains, whereas 20% are conducted of Self-Administered Surveys in stations and the remainder used both venues. Transit agen- Self-administered surveys tend to be distributed and col- cies choose the on-board approach for a variety of reasons. lected by survey staff assigned for this purpose. One or two survey workers are typically assigned to each bus or train A steady flow of riders pass survey workers. On buses car; rail surveys are more likely than are bus surveys to use in particular and trains to some degree all riders pass two surveyors per car. Surveyors offer a questionnaire and through a single point to pay their fare or show a pass. pen or pencil to passengers as they board. Passengers This situation provides a good opportunity for survey return questionnaires to survey workers or place completed workers to offer a questionnaire to each and every questionnaires in envelopes provided at the front and rear person boarding the bus or train. doors. There is adequate time for respondents to complete the survey. The "cost" of completing the survey tends to be Questionnaires often provide the option of return by mail. relatively low, because respondents are spending time The mail-back option is particularly important if respon- on the bus or train anyway. dents do not have sufficient time to complete the survey on Questionnaires can be returned on the spot. Most board, if they may need help from a family member or respondents can complete the questionnaire before friend, or if there is some extenuating circumstance such leaving the bus or train and return it in person. Surveys as they simply need their glasses to be able to complete the completed and returned in this manner will not be mis- survey. Mail-back questionnaires include a postage-paid placed or forgotten, as may happen with surveys taken mailing address on one panel; riders can fold and staple off the vehicle to be completed later. or tape the questionnaire and drop it in the mail. Use of the It is a relatively safe environment for surveyors. The mail option varies. For some surveys, the Washington presence of bus operators and train crews provides a Metropolitan Area Transit Agency (WMATA) and CTTran- measure of safety for survey workers, whereas subway sit (Hartford, Connecticut) reported receiving more than stations or bus stops in untrafficked areas may raise 30% of returned surveys by mail, whereas fewer than issues of personal safety for survey workers. 10% of total surveys were returned by mail in two CTA It facilitates obtaining a representative sample of tran- surveys and in a TriMet survey. sit riders. The advantage of a moving bus or train is that it picks up passengers along an entire route. Therefore, Some surveys are distributed by bus operators or are left a survey may be more likely to obtain a representative on seats or in timetable holders. One-quarter of the on-board sample of riders by surveying on board rather than surveys reported by transit agencies involved bus operators at bus stops or in subway, light rail, or commuter rail distributing the questionnaires (including surveys distributed stations. This is an important consideration for any by a combination of bus operators and survey workers). O&D study and for any study in which rider character- Agencies that use bus operators exclusively to distribute istics vary significantly between neighborhoods. surveys tend to be smaller properties such as Pace Suburban Bus, SMART, Central Florida Regional Transportation The choice of conducting surveys in stations or transit Authority (known as LYNX), city of Lodi (California), and centers tends to be driven by circumstances that are particu- the Capital District Transportation Authority. Apparently, lar to the survey or transit property. When nearly all riders use of bus operators has been more successful at these pass through a downtown transit center or a few transfer smaller agencies; two larger agencies commented that bus points, it may be most time-efficient for survey staff to work operators have been too busy to distribute questionnaires to at these central hubs rather than be spread out across a sub- all riders. There may also be union issues of operators work- stantial number of buses. ing "out of title" if asked to distribute surveys. Some surveys are conducted in rail stations. TriMet con- ducted its Ticket Vending Machine (TVM) Fascia Redesign Prior Notice to Riders survey immediately after respondents had used the TVM. Furthermore, TriMet chose the airport station to interview For 46% of the surveys, the agencies notified passengers riders who were not experienced TVM users. about the survey in advance through media, on-board