1. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 1 SOEP and DOI Requirements and Challenges Jan Goebel

2. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 2 Content 1.SOEP Overview 2.Problems 3.Conclusions

3. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 3 SOEP Overview Socio-Economic Panel Study (SOEP) is a representative longitudinal study of private households in Germany Annual survey since 1984 of about 10,000 households (around 20,000 persons) Some of the many topics include household composition, occupational biographies, employment, earnings, health and indicators of subjective well-being

4. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 4 SOEP is an ongoing Survey Common with all panel surveys Each year we distribute an enhanced version with new and changed data Question are changing, new topics,... → We do a lot but not just replication! Even changes for „archived data“, like a change in the coding scheme of ISCO

5. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 5 The SOEP currently (User DVD) consists of: –More than 320 data files –About 40.000 Variables Granulation to choose for citation? –Complete SOEP distribution of one year? –„Connected“ SOEP parts, e.g. Individual questionnaires, HH-questionnaires, generated datasets –Each data file –Each Variable (for each year or only once, longitudinal concept?) SOEP is not one dataset but a complex data structure

6. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 6 European user: 100% Version (English, German, different formats for SAS/SPSS/Stata/ASCII) Non-EU user: 95% Version (of cases) International comparative research: Part of the CNEF (Cross National Equivalent File) SOEP Geocodes (supplementary CD): Regional Planning Regions, Community types, etc. Country codes, Community codes, zip codes, microm: only by remote execution or at the Research Data Center (RDC SOEP) SOEP Pretests SOEP Related Studies „The SOEP” is available in different versions

7. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 7 SOEP can change during the period, because of updates Updates of weighting schemes or even bug fixes (also possible for older waves) Sometimes more than one update between distributions (cumulative updates?) How can a user know what version she is using? Message-Digest Algorithm (MD5) Secure Hash Algorithm (SHA-2) Universal Numeric Fingerprint (UNF) Does rounding matter? German/English Labels, different formats (SPSS, STATA, …) Only update of a label bug?

8. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 8 Conclusions Nesting of DOI should be possible: PrintDOISOEP exampleSOEP DOI Edited bookSurveySOEP DVD10.1000/soep.26 Article in bookData fileSOEP dataset $PGEN10.1000/soep.26.hgen Table in article in book VariableSOEP dataset $pgen variable ihinc$$ 10.1000/soep.26.hgen.ihinc It should be possible for a user to identify the data, including version  The metadata of a DOI should include a SHA for each data file and format, which must also be persistent, like SHA-2 Commitment about the persistence of the data provider It is not enough to identify the data source to make an scientific empirical analysis reproducible, you normally need the syntax also

9. February 1, 2011 Workshop: Persistent Identifiers for the Social Sciences 9 Thank you for your attention!