We support you in Sampling
Sampling is used to select the people for whom data is to be collected. Only a reliable sample forms the basis for a high-quality survey. We can advise you on the development of a suitable sampling design and, if required, draw the sample for you. We can look back on many years of experience, which enables us to develop an adequate sampling plan for every research problem, including the planning of the sample size. We can also draw on a repertoire of established and innovative methods and a wealth of experience in sample designs for international comparative surveys and advise you on this.
Our Services for Sampling
Drawing of Complex Samples
Complex sampling includes both multi-stage selection procedures and sampling designs with unequal probabilities.The most common case is the drawing of municipalities for population registration office samples. However, multi-stage school samples etc. are also included.
GESIS can be commissioned to implement such complex sampling designs or to draw samples from several selection bases.
The scope and performance of drawing complex samples are adapted as required. In the case of residents' registration office samples, this includes Planning of sample points according to strata, allocation of the total sample to sample points, drawing of municipalities (not: sampling within municipalities). Please note that in the case of very specific sampling bases, such as the selection of schools in a specific area, the sampling basis must be provided by the client.
Drawing of Telephone Samples
Since the end of the 1990s, a frame developed by GESIS (Gabler-Häder design) has established itself as the selection frame for telephone samples in Germany, which contains both registered and non-registered telephone lines that can be reached via a local network. This selection frame is updated twice a year.
As a growing proportion of households can now only be reached by cell phone, the sole use of this selection frame does not adequately cover all private households. For this reason, GESIS has developed a sampling frame for mobile phone samples. This is also available for sampling.
This enables a dual-frame approach in which both a landline and a mobile phone sample are used for a survey and the results can be combined by weighting.
We draw samples for you from this frame for nationwide (or even regional) telephone surveys.
Survey methodology consulting
Do you need further consultingon survey methodology? Our experts will be happy to advise you personally and individually on topics relating to the selection and use of suitable survey instruments, survey design, sampling and survey statistics.
Selected articles of the GESIS Survey Guides:
- Sampling in Theory (177 kB)
- Sampling in Practice (186 kB)
