Web Surveys:

1. Web Surveys: COST 355 WATCH Group 3: Overview of National Transport Survey An opportunity to reduce non-response in traditional household travel surveys BONNEL P., BAYART C.Patrick.bonnel@entpe.frCaroline.bayart@entpe.fr Laboratoire d’Economie des TransportsENTPE, Université Lumière Lyon 2, CNRS

2. Objectives: feasibility of web travel survey Household travel surveys are facing decreasing response rate (53% for Lyon in 2006) • Can we increase response rate when mixing survey modes: face-to-face and web? • Is it possible to collect travel data through web? • Comparability of web data with face-to-face data => target population: households who refuse to respond or are non contactable by the web

3. Methodology Gross sample Face to face survey of 6.375 households for Greater Lyon area Face-to-face interview yes no Web survey Non reachable Out for long duration Refusal On-line survey

4. Why such a passion for web surveys? Democratization of Internet access and data processing encourage web surveys: • Low average cost per contact • Real time data checking • Survey interactivity and customization • Easy and fast to implement • Non intrusive and less burden media => a way to increase data quality by considering non-respondents to traditional surveys

5. Main limitations of web-surveys An innovative method which contains some limits: • Low Internet penetration rate • Net surfers skills and hardware vary a lot • On-line questionnaire are self-administrated • Comparability issues due to specific questionnaire • Concerns with data privacy and server confidentiality => exclusive web survey doesn’t allow to collect representative data

6. Combining survey modes Difficult to carry out efficient household travel surveys with traditional modes • Non-response rate is increasing (35% in 1995 and 47% in 2006) • Some segments seem to be under-represented But face-to-face interviews are useful to gather accurate data and study in-depth behaviors => Give an alternative to people non reachable or who refuse to receive an interviewer at home

7. Survey methodology • Allocation of personal login and password • 1 person surveyed per household • Questionnaire: • Simplification and adaptation for a self-administration • Customisation and filtering • Real-time checking • (nearly) No mandatory response

8. Trip or activity diary? Face to face: trip diary Web: mix of trip and activity diary Departure place and activity Departure time Transport mode Arrival place Arrival time Activity at arrival But activity diary would have been better

9. Sample and administration • 4,379 letters to web sample: • 1st wave: 1,882 beginning of April 2006 • 2nd wave: 2,497 mid-may 2006 • 2 postal reminders: • 1st wave: May and June 2006 • 2nd wave: June 2006

10. Response rate Number of daily connexions 30 25 20 15 10 5 0 04/04/2006 09/04/2006 15/04/2006 22/04/2006 03/05/2006 27/05/2006 01/06/2006 06/06/2006 11/06/2006 17/06/2006 22/06/2006 28/06/2006 03/07/2006 08/07/2006 14/07/2006

11. Response rate • 537 individual connexions: • Connexion rate: 12,5% • 364 full response: • Response rate 8,3% • but 369 usable interviews (stop after trip diary)

12. First results 3 trips per person in average

13. First results: Reason to respond by web

14. Results: web population • Women are over-represented (57%) • 43 years old in average with gender differences (men = 46, women = 41) • Working population : 73% • But few students (5%) and retired persons (13%)

15. Results: web population • They belong to high classes: • 66% of university level • Near 40% are higher managerial and professional • Only 4% unemployed • High car ownership : • 91% with a driving license • 41% of households own one car, 50% own 2 cars or more

16. Perspectives • Assess web potential for travel surveys • Compare daily mobility pattern according to response mode • Study net surfers behavior when they fill out the on-line questionnaire • Give technical specifications to run other household travel surveys