Title: SOEP Innovation Sample (SOEP-IS), data from 1998-2019
DOI : 10.5684/soep.is.2019
Collection period: 1998-2019
Publication date: 2021-05-06
Principal investigators: Jan Goebel, Stefan Liebig, David Richter, Carsten Schröder, Jürgen Schupp, Knut Wenzig
Data collector: Kantar Public Deutschland GmbH
Population: Persons living in private households in Germany.
Selection method: All samples of SOEP are multi-stage random samples which are regionally clustered. The respondents (households) are selected by random-walk.
Collection mode: The SOEP-IS is conducted using CAPI (Computer-assisted personal interviewing) exclusively. In principle, an interviewer tries to obtain face-to-face interviews with all members of a given survey household aged 16 and over. Additionally, one person (head of household) is asked to complete a household questionnaire covering information on housing, housing costs, and different sources of income. This also includes some questions about children up to 16 years of age in the household (e.g., kindergarten attendance, elementary school attendance, etc.).
An error occurred in the 2017 release, concerning several activity-related variables of the p-dataset (pli0090, pli0091, pli0092, pli0096, pli0097, pli0098). In the p-dataset, these variables have five possible positive responses,
" Daily", " At least once a week", " At least once a month", " Seldom" and " Never".
This reflects how the questions were asked in several specific survey years – in other survey years, however, the "Daily"-option was not included in the questionnaire and only
" At least once a week", " At least once a month", " Seldom" and " Never" were possible responses.
To account for this difference in the final dataset, we have been recoding the latter version to fit to the first one (i.e., " At least once a week" to " At least once a week", etc.) in previous years. Unfortunately, this recoding was not performed for the 2017 data, resulting in original " At least once a week"-responses being reported as " Daily"-responses in the final dataset, " At least once a month"-responses as " At least once a week"-responses and so forth.
This error only concerned the 2017 responses for the variables mentioned above and has been fixed in the new 2019 release version. It should be noted that in the 2019 interviews, the full scale with 5 possible responses has been used again. To highlight that two different response scales have been used over the years (1-4 and 1-5), we have created additional copies of these variables with a suffix ("*_v1" and "*_v2"). These copies only include the respective original scales without any recoding.