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Data harmonization at all levels

For many research projects and infrastructure tasks, it is necessary to be able to combine data from different sources. Here, the comparability of data across time, countries, survey programs, and measurement instruments must be established and often subsequently improved. GESIS offers comprehensive consulting services and various resources to help you improve the comparability of existing data.

Furthermore, we continuously work to advance methods in the context of data harmonization and to offer new data products. We are open to cooperation requests in these topics.

Our services and tools for your data harmonization

Are you faced with the task of harmonizing data from your research project? Our tools and resources can provide you with assistance.

ZIS

The Open Access Repository for Measurement Instruments ZIS supplies single and multi-item measurement instruments (short scales and long forms) for social- and behavioral concepts that have been evaluated for usage in questionnaires and social surveys. Using validated instruments supports increasing the comparability across studies and new data collections.

In the metadata portal MISSY, the German Microdata Lab provides structured information on selected data of official statistics at study, country, and variable level. The digital preparation of the metadata enables research-relevant information to be found quickly and particularly facilitates the variable comparison across survey years and countries. In addition, researchers can find original documents from the statistical offices or from Eurostat in MISSY, as well as helpful tools for preparing and analysing the data.

QuestionLink provides recoding scripts with which measurement instruments for selected concepts can be made comparable. The focus of QuestionLink lies on German single-item instruments for latent constructs, such as interest, attitudes, subjective evaluations, or values.

Harmonized data products - projects and cumulations

GESIS offers different harmonized data products that you can reuse. This includes harmonization projects which combined data across different infrastructures (i.e., survey programs) as well as cumulations which bundle waves within one infrastructure.

Extensive harmonization of survey and especially biographical data has not been common in the social sciences. HaSpaD (Harmonizing and synthesizing partnership histories) provides a tool for harmonizing and accumulating, and thus comprehensively analyzing, survey-based longitudinal data sets on partnership biographies.

By harmonization, cumulation, and linking of survey-, as well as macro data, the ONBound project (Old and new boundaries: National Identities and Religion) has created a unique database for the social sciences that enables researchers to explore the interlinking of national and religious identities on multiple levels. For reuse, ONBound provides syntax files that allow users to create customized datasets in SPSS or STATA format by harmonizing and linking data across a selectable number of countries.

The ALLBUS cumulation contains harmonized time series for all data collected at least twice throughout the ALLBUS survey-rounds. The cumulation data are therefore particularly suitable for analyses of time series in studies of social change. For most of the topical modules (e.g., political attitudes, social inequality, etc.), 3 to 4 measurement time-points are now available. Central socio-demographic characteristics have been surveyed even more frequently. The accompanying documentation provides information on changes in question formats and formulations over time.

The Eurobarometer is a long-running European survey collection conducted on behalf of the European Commission and the European Parliament. It consists of several sub-series with many repeated questions over time, thus enabling the cross-national analysis of trends for many relevant issues. Therefore, this potential for longitudinal data harmonization has led to several efforts of cumulating the data, at times with direct involvement by GESIS.

GESIS provides SPSS routines to harmonize and cumulate all German Microcensuses available to the scientific community from 1962 to 2016. The resulting GESIS Microcensus-Trendfile thus covers a period of five and a half decades. It contains nearly 20 million cases and more than 160 variables from various fields and allows both long-term and in-depth analyses of social change in (West) Germany.

For the ISSP module topics “Role of Government”, “National Identity”, “Religion”, and “Social Inequality” we offer cumulated data sets. They are designed to facilitate cross-national comparative analyses over time and cover up to five waves of social attitudes and behavior data over more than three decades. Such trend files contain data from all ISSP member countries that participated in the module topic at least twice.