Data Collection Methods In Transportation Planning

Many data collection methods Customer satisfaction: http://www.dot.ca.gov/hq/maint/external_survey/2005_survey/index.htm Public involvement : http://www.101inmotion.com/

Data Collection Methods Traffic monitoring: Loop detector data (presence, speed, vehicle class) Used to provide historical records of use and real time information to motorists: http://www.dot.ca.gov/traffic/ Traffic cameras: http://video.dot.ca.gov/

Queen of Data Collection Methods Travel Survey Queen of Data Collection Methods

Design of a Survey It is a process with many feedback loops Many choices depend on the reason we collect data Data as the base inventory Data for models and simulations Data for public involvement Data for monitoring change (before-after) It is heavily influenced by time and money budgets Heavily quantitative but qualitative emerges as potentially powerful It reflects the designers model of society or explicit/implicit models of funding agencies

Richardson-Ampt-Meyburg Survey Methods for Transport Planning Survey Process Richardson-Ampt-Meyburg Survey Methods for Transport Planning Eucalyptus Press

Emerging Research Direction in Travel Behavior Human Interaction Emerging Research Direction in Travel Behavior

A family’s day in South Perth Male, 40 years, full time worker, driver A family’s day in South Perth Female, 36 years, home duties full time, driver Male, 6 years, primary school Male, 5 years, primary school Figure by Pribyl

Another family’s day in Male, 47 years, full time worker, driver Another family’s day in South Perth Female, 42 years, home duties full time, driver Female, 8 years, primary school Male, 5 years, primary school Figure by Pribyl

10 Steps to Successful Surveys (Salant & Dillman) Understand and avoid the four kinds of error Be specific about what information you seek and why Choose the survey method that will work best Decide whether and how to sample Write good questions Design and test the questionnaire Assemble the necessary resources Code, computerize and analyze the data Present your results Maintain perspective Reports and presentations Types of Error

Coverage Error Occurs when the list (sampling frame) from which the sample is drawn does not include all segments of the population that we want study/model The list used is not accurate and up-to-date

Sampling Error Occurs because the survey does not cover the entire population – it is not a census Always happens to some extent Reduces by increasing the sample size

Measurement Error Occurs when a respondent’s answer to a question is inaccurate, imprecise or in any other way unusable These errors come from— the survey method, the questionnaire, the interviewer, and the respondent Relatively easier for the researcher to control using statistical methods

Non-Response Error Occurs when a significant number of people in the sample do not respond to the questionnaire and are different from those that do in some way (this is also named selectivity bias in models) This is a main reason to maximize the response rate

Main Types of Surveys Mail surveys Telephone surveys Face-to-face surveys Internet surveys (immobile and mobile)

When to Use Mail Surveys You have a reliable address list The people in the population will respond accurately and completely by mail An immediate turnaround is not required Resources are relatively scarce but you have considerable amount of time Examples of lists: Driver license rolls Membership lists Assumes a certain level of literacy

When to Use Telephone Surveys The members of the population are very likely to have telephones The questions are relatively straightforward Experienced help is available A quick turnaround is important Only about 90% of Americans have phones Examples w/no phones: The poor, migrant workers, retired who travel a lot You need experienced interviewers

When to Face-to-Face Surveys There is no list of the population You need to collect information from people who are not likely to respond willingly or accurately by mail or telephone The questionnaire is complex Well-funded projects Experienced interviewers are available Example of no list: Tourists at an attraction The homeless Non-respondents Illiterate Elderly and infirm

Maximize the Reward for Responding Show the respondent positive regard Give verbal appreciation Use a “consulting” approach Support the respondents values Offer tangible rewards Make the questionnaire interesting Consulting approach They have the information you need “It is not known what people like you think about this issue, so we are asking you.”

Minimize the Cost of Responding Make the task appear brief Reduce the physical and mental effort required Eliminate chances of embarrassment Eliminate any implication of subordination Eliminate any direct monetary cost

Establish Trust With the Respondent Provide a token of appreciation in advance Identify with a known organization that has legitimacy Build on other exchange relationships

Schedule for the next few weeks Today (10/16/06) Section survey type Next week (10/23/06) Data collection methods part 2… components of surveys. Section broken into groups Start writing questions 10/30/06 Issues with components, continue writing questions 10/31/06 Check for redundancy in survey (lecture) 11/3/06 (Friday) Component due to me

Questions for reading about survey type What is the Daily Reconstruction Method (or Time Use Diary)? What are the advantages of this survey type? What are the main categories or sections (components) of the survey? Start thinking about how you would implement this technique in transportation (challenge: DRM in transportation setting, time use with attitudes and perceptions). Write a 1 page MAX summary about your survey method with these questions in mind. EMAIL TO ME BY THIS FRIDAY!!!!!!!