Kvoturval

Kvoturval, or quota sampling, is a non-probability sampling method used in social science and market research. It aims to reflect the distribution of certain characteristics by selecting participants to fill predefined subgroups in the same proportions as in the target population. The method relies on non-random selection and researcher judgment rather than random sampling.

To implement kvoturval, researchers identify relevant characteristics (for example gender, age, region, education) and determine quotas that mirror the population. Fieldwork proceeds by recruiting respondents who fit the remaining quotas until all quotas are satisfied. Because the selection process is not random, the resulting sample is not guaranteed to be statistically representative.

Kvoturval offers practical advantages, including speed, lower cost, and the ability to ensure representation of key subgroups, which can be important for subgroup analyses. It is commonly used in market research, quick opinion polls, and exploratory studies where precise generalization is not required.

Limitations include selection bias, as recruiters influence who is included; nonresponse bias, if certain groups participate less readily; and the inability to compute unbiased probability-based confidence intervals or standard errors. While weighting can adjust for known differences, it cannot fully restore randomness. Kvoturval should be used with awareness of these limitations and, when possible, complemented by probabilistic sampling methods.