This brief provides general information about our proceedings for collecting population data. Information about specific surveys are presented as online supplementary material in relation to papers we publish.
The aim with the population surveys is to gather information from a representative sample of the population in one or several countries. Survey questions and vignettes are developed in English by one or several of the staff at the Centre for Research on Discretion and Paternalism, and sometimes design is developed in collaboration with external partners. Data is delivered by a data collection firm, and we have so far used Respons Analyse, Norstat and Gallup. For Norstat and Respons data is typically collected via an omnibus. Selection of data collection firm will typically be based on a best value for money assessment after a bidding process.
For this type of research, there is not an obligation to report the project to the Norwegian Data Protection Office for Research nor the Data Protection Officer at the University of Bergen, since the data material the researchers receive is anonymous and cannot be traced back, directly or indirectly, to specific individuals or groups of individuals.
Distribution via Omnibus
An omnibus survey covers a range of topics of interest. It has either multiple sponsors, or is designed to generate data useful to a broad segment of the social science community rather than answer one particular research question (Bachmann & Schutt 2014). There are both strengths and weaknesses in using an omnibus to gather survey data. Positive aspects are that it is both a cost and time effective way to reach a large number of people that one otherwise might not have been able to, and the data material can easily become a large-scale representative sample which one can use for generalizable results. The weaknesses are related to the fact that an independent company runs the survey, so they are in charge of the structure and format of the survey itself and respond to several different clients at the same time. Thus, one cannot ask complicated or a great number of questions. It can also be the case that other topics in the omnibus interfere with the ‘vibe’ of the questions the researcher has included. For the background questions, there is a set of standard formulations provided by the data collection firm, and in additions at an additional cost the researchers may request specific information about such matters as religious and political orientation, as well as migration background.
Weight survey samples
To secure representativeness, the survey material is weighted by the data collection company. With a known distribution of a population on three dimensions, sex, age and geography, survey responses are weighted so that population surveys are nationally representative. The reason for using weights is to achieve as similar as possible as the real distribution in the given population. The weights are represented by a single variable in the datasets named “weight” and the figures will naturally vary for each respondent. The closer the number in the column “weight” is to 1, the better, as this indicates that we have an approximately equal distribution in the survey sample as in the distribution in the population.