View
5
Download
0
Category
Preview:
Citation preview
KIT – University of the State of Baden-Wuerttemberg and
National Research Center of the Helmholtz Association www.kit.edu
INSTITUTE FOR TRANSPORT STUDIES
Answer Young People Just Like Old People? – Impacts and Consequences of Different Household Travel Survey Methods Dr.-Ing. Martin Kagerbauer
7 March 2013 New Techniques and Technologies for Statistics (NTTS), Session 17C: Special session on COST/Shanti, Brussels
2 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Agenda
Background of the survey
Different methods of the survey
Comparison of the different survey methods
Response rates, sample sizes, types of households, car-ownership, age, profession, season tickets for public transport
Mobility key figures, modal split and trip purpose
Conclusion and Outlook
3 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Background of the survey
Region of Stuttgart
Conurbation of 179 cities and boroughs
A total of about 2.7 million inhabitants
Household Travel Survey
5,500 households
Multi-day survey
Duration one week
Objectives of the Survey
Update the mobility database
Input for a transport demand model (microscopic and macroscopic)
Information about variability and stability of travel behaviour
4 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Background of the survey
Data collected during the survey
Socio-demographic data concerning the household and all persons living in the household
Trip data with location of origin and destination (transferred into geocodes)
Survey is based on German Mobility Panel (MOP) and combines other survey designs
Sample size
Verification
Sample
Main
Sample
Methode for large
sample size
Check against MOP
Regional Data MiD, ...
Quality assurance Efficiency
5 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Background of the survey
Sample size
Verification Sample approx. 1,000 HH
Main Sample approx.
4,500 HH
PAPI method (paper-pencil-interview)
following the design of the German Mobility Panel
CAWI-method (computer-assisted-
web-interview)
CATI-method (computer-assisted-
telephone-interview)
Survey methods
A lot of questions „Only“ questions required for modelling
6 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Different methods of the survey
PAPI method (Paper-Pencil-interview)
Household and person questionnaire (e.g. number of persons/children living in the household, number of cars, information about the cars, parking situation, public transport situation , sex, age , profession, car and public transport availability etc.)
Trip diary (start and end time of trip, modes used, trip purpose, duration, trip length)
Questionnaire is sent back by mail and plausibility checked
Design based on German Mobility Panel (MOP)
Allows benchmarking without methodological differences
Time-tested method and common practice in Germany
The PAPI-sample serves as verification sample in the comparison of the different survey methods
7 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Different methods of the survey
CATI method (computer-assisted-telephone-interview)
Participants are asked to report their trips by phone
All participants are called two or three times during the survey period and asked to report their trips
Trips are entered into the computer directly
The data is immediately plausibility checked
In case of mistakes in the data, interviewer can ask participants immediately to clarify
Disadvantage: Participants can forget some trips in the haste of a telephone call
Innovative method in multi-day surveys but common practice in cross-sectional surveys in Germany
8 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Different methods of the survey
CAWI method (computer-assisted-web-interview)
Participants report their trips via internet in a software tool
Data is checked one day at a time
In case of mistakes, participants are contacted and asked to give missing information
Participants can take part in the survey at any time they want
Disadvantage: Participants do not answer very thoroughly
Innovative method in multi-day surveys tested in cross-sectional surveys in Germany
9 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Different methods of the survey
Survey procedure
Total sample size (5,500 Households)
Households are randomly drawn (registration offices)
Only mailing address provided
Merge telephone numbers, if possible
Verification Sample (1,000 Households)
Main Sample (4,500 Households)
Random division of the total sample to two subsamples
Contacting the participants
First contact by mail, introducing the survey and asking to participate
When phone number available: another contact by phone (this generally leads to higher response rates than only mail)
Participant can choose between CATI and CAWI-methode
CATI-Sample CAWI-Sample
Questionnaires Memory jogger and calls Web access
10 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Response rates
CATI+CAWI very similar to PAPI
CATI CAWI CATI+CAWI PAPI
Ratio of households successfully surveyed [%]
(=useful questionnaires / sample size)8.1% 8.8%
Ratio of households willing to participate [%]
(=households willing to participate / sample size)16.7% 15.1%
Ratio of households successfully surveyed [%]
(=useful questionnaires / households willing to participate )64.1% 39.7% 51.8% 63.0%
Response ratesStuttgart Region Survey 2009
Not applicable due to
the survey method
Not applicable due to
the survey method
In CATI more of the households willing to participate actually take part in the survey then in CAWI
Participants in CATI are more reliable
11 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Types of households
Overall comparison between PAPI and CATI+CAWI is similar
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [housholds] 2,215 2,250 4,465 1,096 5,561
Single household 7.1% 12.2% 9.7% 8.0% 9.4%
Couple household without children 11.2% 22.0% 16.7% 20.0% 17.3%
Family or single parent household with children < 19 years 19.6% 33.9% 26.8% 25.5% 26.5%
Senior household 49.7% 17.5% 33.5% 28.2% 32.4%
Multi-person-household without children < 19 years 12.5% 14.4% 13.4% 16.8% 14.1%
No classification 0.0% 0.0% 0.0% 1.6% 0.3%
Types of households
Stuttgart Region Survey 2009
Share of senior households high in CATI and very low in CAWI.
Share of single, couple and single parents households high in CAWI and very low in CATI
Seniors are available by telephone and not so familiar with technology
Single persons and couples without children are hard to reach by phone but more familiar with internet
12 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Age of the persons
CATI: High share of elderly and smaller share of younger people (19 to 34 years)
CAWI: Smaller share of elderly and high share of teens and middle aged people
PAPI: Gap between people with 19 to 34 years (less) and 35 to 64 years (more)
Results for CATI+CAWI compared with PAPI method are similar
It is difficult to reach elderly people with the CAWI method and similarly difficult to reach the age group between19-34 for CATI
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [persons] 5,166 6,149 11,315 2,852 14,167 2,679,000
0 to 18 years 20.3% 27.2% 24.0% 23.6% 23.9% 18.8%
19 to 34 years 8.7% 15.6% 12.5% 11.3% 12.2% 19.6%
35 to 64 years 38.3% 46.5% 42.7% 46.7% 43.5% 41.9%
65 years and older 32.7% 10.7% 20.8% 17.5% 20.1% 19.7%
Not specified 0.0% 0.0% 0.0% 1.0% 0.2% 0.0%
Age
Stuttgart Region Survey 2009 Stuttgart Region
population
parameter
13 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Profession of the persons
CATI: High ratio of retired persons and low ratio of fully working people
CAWI: Low ratio of retired persons and high ratio of fully working people
PAPI: Similar to CATI+CAWI
Only CAWI and CATI represent all professions primarily the fully working and the retired people
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [persons] 5,166 6,149 11,315 2,852 14,167
Fully working 22.2% 32.8% 28.0% 29.2% 28.2%
Partly working 10.8% 13.6% 12.3% 14.1% 12.7%
Not working/ jobless 6.2% 7.7% 7.0% 7.6% 7.1%
In education 18.8% 23.9% 21.6% 23.9% 22.1%
Retired person 35.9% 11.9% 22.9% 19.5% 22.2%
Not specified 6.1% 10.1% 8.3% 5.8% 7.8%
Profession
Stuttgart Region Survey 2009
14 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Mobility key figures
Lower share of trip makers and lower amount of kilometers per day in CATI due to higher ratio of elderly persons
No significant differences between the methods for the trips per person
Number of kilometers per day and the time spent for transport are higher in CAWI than in CATI (as a follow: different levels of speed and trip length)
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [person-days] 34,496 39,585 74,081 16,653 90,734
Trip makers [%] 84% 87% 86% 90% 87%
Trips per person and day [no] 3.0 3.1 3.0 3.1 3.0
Kilometres per person and day [km] 29.5 34.9 32.3 35.3 32.9
Minutes per person and day [min] 74 77 76 72 75
Average speed [km/h] 24.1 27.0 25.7 29.4 26.4
Average trip length 9.9 11.4 10.7 11.2 10.8
Mobility key figures
Stuttgart Region Survey 2009
T-test: Kilometers and travel time differ significantly between the methods
15 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Modal Split
Similar results for all survey methods
Small difference for “foot”: Share is higher for CATI method
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [person-days] 34,496 39,585 74,081 16,653 90,734
Foot 27.6% 22.9% 25.0% 22.3% 24.5%
Bike 4.3% 5.5% 4.9% 4.6% 4.9%
Motorcycle and car as driver 42.6% 44.1% 43.5% 47.2% 44.1%
Car as passenger 13.8% 13.4% 13.6% 13.2% 13.5%
Public Transport (Bus, rapid transit) 10.5% 12.3% 11.4% 10.6% 11.3%
Railway 1.1% 1.6% 1.4% 1.8% 1.5%
Others 0.1% 0.2% 0.2% 0.3% 0.2%
Modal split
Stuttgart Region Survey 2009
Methodical effect : In a telephone interview, the interviewer can immediately ask about forgotten trips, especially short trips made by foot
16 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Comparison of the different survey methods
Trip Purpose
Combination of CATI+CATI show similar results as PAPI method
CATI CAWI CATI+CAWI PAPIALL
(CATI+CAWI+PAPI)
Sample size [person-days] 34,496 39,585 74,081 16,653 90,734
Work 7.7% 11.6% 9.8% 10.3% 9.9%
Buisiness trips 1.2% 2.1% 1.7% 2.4% 1.8%
Education 3.7% 5.1% 4.5% 3.9% 4.4%
Leisure 18.5% 16.1% 17.2% 15.8% 16.9%
Shopping 11.6% 9.5% 10.4% 9.9% 10.3%
Visitation 12.5% 9.9% 11.1% 11.8% 11.2%
Service 4.3% 4.8% 4.6% 4.6% 4.6%
Others 0.2% 0.5% 0.4% 0.8% 0.5%
Back home 40.3% 40.4% 40.4% 40.5% 40.4%
Trip purpose
Stuttgart Region Survey 2009
CATI: Share of „work“ and „business“ is lower due to high share of retiree
CAWI: Share of „education“ is high due to high ratio of young persons
17 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Significant differences between CATI and CAWI methods
Younger people have strong preference to join CAWI survey
Elderly or retired people clearly favor telephone interview
Conclusions and Outlook
PAPI method
Works well and provides reliable results without unexpected non-response effects
CATI + CAWI method
Combination of CATI and CAWI method provides similar results to PAPI method
As a result, most key figures of household and person attributes as well as mobility behavior are affected for both CATI and CAWI method
18 Kagerbauer
Answer Young People Just Like Old People? – Impacts and Consequences of Travel Survey Methods
New Techniques and Technologies for Statistics (NTTS), Brussels Institute for Transport Studies
Conclusions and Outlook
CAWI method alone leads to massive overrepresentation of younger people CATI method alone leads to overrepresentation of elderly people
Combination of CAWI method with more approved methods (especially CATI) is recommended
But: Combination of different survey methods leads to higher costs and complexity of survey
KIT – University of the State of Baden-Wuerttemberg and
National Research Center of the Helmholtz Association www.kit.edu
INSTITUTE FOR TRANSPORT STUDIES
Answer Young People Just Like Old People? –
Impacts and Consequences of Different
Household Travel Survey Methods
Dr.-Ing. Martin Kagerbauer, Karlsruhe Institute of Technology (KIT), Institute for Transport Studies kagerbauer@kit.edu (eMail) +49 (721) 608-47734 (phone)
Thank you for your attention !
Recommended