Implementing cawi into the data collection process Kees van Berkel Mariëtte Vosmer Jerusalem, July 2013

Implementing cawi into data collection process 1 Why Meet customers’ demands; Meet respondents’ expectations; Budget cuts. It’s all about the money; Increase response rates, reach more groups. Be flexible

Implementing cawi into data collection process 2 History 2005: start web data collection research; 2005 – 2007: experiments ICT-survey Crime survey Survey measuring Underground Economy; 2008 – now: surveys Dutch Housing and Living survey Crime survey National Mobility survey Health Survey Labour Force Survey;

Implementing cawi into data collection process 3 Sampling frame Municipal basic registration of population data. This registration contains information of all people who are registered at a municipality. The municipalities own the data, but the Ministry of the Interior and Kingdom Relations is responsible for the regulation. Statistics Netherlands is allowed to use it, under strict conditions.

Implementing cawi into data collection process 4 Sampling design First stage: stratified systematic pps sample of municipalities. Second stage: random sample of addresses. The sample is self-weighting: Every address has the same inclusion probability. Stratification: the country is split into 40 corop areas.

Implementing cawi into data collection process 5 Sampling design m : desired number of addresses to be selected in each selected municipality  cluster size. g h : number of municipalities to be selected in stratum h. In each stratum h : the number of addresses to be drawn n h is proportional to the number of addresses N h,

Implementing cawi into data collection process 6 Sampling design Small m  many municipalities  large travelling expences Large m  few municipalities  cluster effect  large standard errors Face to face: cluster size m = 12 Mixed-mode: cluster size m = 1

Implementing cawi into data collection process 7 Fixed amounts Cawi respons Cawi non-respons Capi Cati Increase of variance

Implementing cawi into data collection process 8 Weighting procedure Mode included as weighting term Increase of inclusion weights due to partially approaching cawi non respondents by telephone or face to face

Implementing cawi into data collection process 9 Approach strategy Approach letter Reminder 1 Reminder 2 TelephoneFace to face + + +

LFS adaptations Implementing cawi into data collection process 10 > 2 or > 3 in the age of 15 years or more to capi? 1) 2) Quality of phone numbers

Implementing cawi into data collection process 11 Distribution of responses in time

Implementing cawi into data collection process 12 Response rates

Implementing cawi into data collection process 13 Response results LFS (1)

Implementing cawi into data collection process 14 Response results LFS (3)