Katselukerroinluku

Katselukerroinluku is a statistical metric used in Finnish media research to express the factor by which observed viewing data are adjusted to represent a target population. The exact definition and calculation can vary between organizations, but the concept generally functions as a multiplier or weight applied to survey or measurement results to improve their generalizability.

Use and purpose

The katselukerroinluku is employed in audience measurement to extrapolate data collected from samples to the broader population, enabling estimates of reach, frequency, and total viewing time. It supports planning and budgeting for broadcasters and advertisers by providing a more representative basis for comparing programs, time slots, or platforms. In practice, the coefficient helps convert sample-derived metrics into population-level indicators.

Calculation and interpretation

In many applications, the katselukerroinluku arises from weighting survey responses to align with known population characteristics such as age, gender, region, and household composition. Weights may be calibrated against external benchmarks and adjusted for factors like time of day or platform (television, online streaming). The resulting value is a modifier that, when applied to observed data, yields population-representative estimates.

Limitations and context

As a derived statistic, the katselukerroinluku depends on methodology, sampling design, and weighting assumptions. Mis-specification of weights or biases in survey data can lead to biased estimates. With increasing cross-platform viewing, definitions and calculations of the coefficient may evolve, requiring ongoing methodological validation.

See also: audience measurement, weighting, sampling, television ratings, reach and frequency.