Longitudinal weights can now be applied to any analysis of data from the first five waves of the self-completion panel survey (CRONOS-3) – fielded as part of the Infra4NextGen project.
Each wave contains about 18-20 items for each of the five pillars of the project, which are the key areas of the NextGenerationEU recovery plan: Digital, Equal, Green, Healthy and Strong.
Users can now combine the data from the five waves and analyse items from each theme together, using these longitudinal weights.
The new longitudinal weight (longweight) and a version of the weights that excludes the population size corrections (longpspwt) should be used for all analysis if two or more waves are combined.
These weights should therefore be applied to analysis that uses the integrated file with all five waves combined, as well as when analysing data from two or more of the first five waves together.
These longitudinal weights are similar to the weights released for each individual wave but have been adjusted to account for the likelihood of panellists responding to all five waves.
The adjustments are based on a logistic model with a range of predictors from responses given to the main European Social Survey Rounds 10 and 11, from where panellists were recruited, as well as CRONOS-3 Wave 2, which was used as the baseline since it is the wave with the largest number of respondents.
For data collection using probability-based samples, every person in the target population should have the same probability of being included in the sample.
When analysing data, the likelihood of each respondent being part of the sample should also be considered, meaning that the most accurate estimates will only be obtained after weighting the data.
Survey data is weighted to ensure that it is nationally representative of the population in each participating country and makes adjustments based on the sample of respondents who actually participate.
For all analysis of data from a single CRONOS-3 wave, it is recommended that users should always use wxweight as a weight, where x indicates the survey Wave.
We also provide a version of the weights that excludes the population size correction, wxpspwght, which can be used for single country analysis or for cross-country comparisons. For these types of analyses, wave weights should give the same estimates.
Respondents recruited at the end of face-to-face interviews in 11 countries during rounds 10 and 11 (2020-24) of the European Social Survey (ESS) were invited to complete each wave the panel.
Panellists in Austria, Belgium, Czechia, Finland, France, Hungary, Iceland, Poland, Portugal, Slovenia, and the United Kingdom were invited to participate in each wave either online or using paper self-completion questionnaires.
The data from the five waves of the CRONOS-3 panel, administered through the Infra4NextGen project, as well as data from CRONOS-3 Wave 6, administered as part of the SoGreen project, is now available on the ESS Data Portal.
Questions across all five waves were developed by the CRONOS team at ESS HQ based at City St George’s, University of London with support from the academic experts for each theme, as well as policy experts from the Joint Research Centre of the European Commission.
All the data is available free of charge via the ESS Data Portal
View data from all 450 questions fielded across five waves by theme: Browse by Theme
