You have not found the information you were looking for? Please have a look at our list of most frequently asked questions.

# 1: How can I apply for the CILS4EU data?

You will find a comprehensive description of how to apply for the data on the webpage of the GESIS Data Archive for the Social Sciences - just click here and decide which version you want to apply for.

# 2: Should I apply for the full version or the reduced version of the data set?

Of course, there is no general answer to that question. But we want to emphasize that the reduced version constitutes still a very informative and workable data set. Our codebook (specifically Appendix F) gives you an excellent overview about all variables that were not included or edited in the reduced version. Feel free to inform yourself if the information you are looking for will be sufficiently included.

# 3: I want to learn more about the CILS4EU data. Are there any opportunities or conferences to get to know the data?

We do not only provide our users with unique data, we also organize events where we introduce them to the structure and specificities of it. Have a quick look into our section current announcements. There we offer soon our future data user events for the year 2016.

# 4: Is it possible that a variable is completely missing in the data set I have been delivered?

Before publishing our data sets and sharing it with researchers all over the world, CILS4EU data are accurately checked in an extensive procedure. Please have a look into the enclosed codebook to reassure possible reasons for missing variables and/or cases. For example, some items could not be asked in all of the four countries due to several restrictions.

If this remains an issue, please approach our contact persons at the GESIS Data Archive for the Social Sciences in Cologne first:

GESIS, Team Data Service
Phone:  + 49 221/476-94-420

# 5: I discovered in the data set a couple of variable names ending with certain characters (e.g. generationG). What does this character mean?

Generally, any character indicates this is a variable that has been somehow adapted throughout the data cleaning process. The subsequent table offers more information on the exact connotation:





Generated variables

The generational status variable generationG was generated using information provided by the child about his or her country of birth and age upon arrival as well as information provided in the parental interview about the biological parents’ countries of birth as well as the grandparents’ countries of birth.


Country-specific variables

Due to divergent educational systems in the four CILS4EU countries, categories for idealistic educational aspirations differ sharply between countries. Therefore, a country-specific variable y1_edasp1CS is included in the data set that contains a total of 20 categories for every answer possibility in the four countries.


Harmonized variables

Idealistic educational aspirations y1_edasp1H were harmonized for England, Germany, the Netherlands and Sweden. This means that educational degrees were made comparable in the respective harmonized variables by combining several categories. The harmonized variable distinguishes “no degree”, “degree below upper secondary school”, “degree from upper secondary school and “university”. Original answers are still available in the country specific variables (see above).


Reduced-version variables

Complete information on the respondent’s concrete country of birth y1_cob is not available in the reduced version of the data. Instead, we offer a reduced version of this variable y1_cobRV, which distinguishes whether the respondent was born in the survey country or not. This variable is also included in the full version of the data.

# 6: The data contains various negative values. What is the exact meaning of these missing codes?

CILS4EU has developed a comprehensive framework allowing to distinguish easily between several sort of missing values. It is constantly adopted for each data set and thus does not change over the waves. The meaning of the negative values is the following:





Don’t know

Only if this option was provided in the questionnaire


No answer

No box ticked/no answer given


Not applicable

Not answered due to filter question


Question not asked

Not asked in a country/mode


Other missing

Answers that could not be coded, fun answers


Interrupted Interview

Only for telephone and online modes


Not available in reduced version

Answers not available in the download version

# 7: I want to publish my work with the CILS4EU data. Do I have to cite it in a specific manner?

Yes, you should indeed follow our citation guidelines for CILS4EU data and documentation. Please have a look into this section here.

# final: To whom should I address with further questions or feedback related to the data sets or to the application procedure?

Please feel free to approach our contact persons at the GESIS Data Archive for the Social Sciences in Cologne, Germany.

-> contact information:

GESIS, Team Data Service
Phone:  + 49 221/476-94-420