Kiintiöotantaan

Kiintiöotantaan, often translated as quota sampling, is a non-probability sampling technique used in market research and opinion polls. It involves dividing the population into mutually exclusive subgroups, called strata, based on certain characteristics such as age, gender, socioeconomic status, or geographic location. The researcher then sets quotas for the number of participants to be selected from each stratum.

Unlike stratified random sampling, where participants are randomly selected within each stratum, quota sampling allows for convenience sampling within each subgroup until the quota is met. This means that the individuals selected within each stratum are not chosen randomly, which can introduce bias. The primary goal of quota sampling is to ensure that the sample reflects the proportions of certain characteristics in the target population.

The advantage of quota sampling is its relative ease and speed of implementation, making it a cost-effective method for obtaining a sample that appears representative. However, its non-random nature means that it is not suitable for studies requiring high statistical precision or generalizability to the wider population. The selection process within quotas can be influenced by researcher bias, potentially leading to a sample that is not truly representative of the population despite meeting the set quotas. It is often used in exploratory research or when random sampling is impractical or too expensive.