Utvalgsestimert

Utvalgsestimert is a term used in statistics to describe a quantity that has been estimated from a sample rather than measured directly in the entire population. The corresponding noun is utvalgsestimat, or utvalgsestimert verdi, referring to the numerical result produced by applying an estimator to the data collected from a sample. In practice, population parameters such as the mean, proportion or variance are often unknown and must be inferred from a sample; the estimators produce utvalgsestimert values of these parameters.

A typical process involves choosing an estimator and calculating it from the sample data. For example, the sample mean is an utvalgsestimert value of the population mean, the sample proportion estimates the population proportion, and the sample variance estimates the population variance. The reliability of utvalgsestimert values depends on the estimator and the sampling design.

Statistical properties such as bias, variance and consistency describe how close an utvalgsestimert value is expected to be to the true population parameter. The standard error and confidence intervals quantify uncertainty around the utvalgsestimert estimate. Under regular conditions, the distribution of estimators can be approximated (for example by the normal distribution via the central limit theorem), enabling hypothesis tests and interval estimates.

Practical considerations include the sampling method, sample size, nonresponse and weighting, which can affect the accuracy and representativeness of utvalgsestimert values. The concept is central to inferential statistics, where conclusions about a population are based on sample-derived estimates.