Mittaasteikot

Mittaasteikot is a Finnish term used in measurement theory to describe the scales by which attributes are quantified. They classify data according to what mathematical operations and statistical analyses are meaningful, guiding how researchers collect, summarize, and compare information. In Finnish scholarly writing the term covers both physical measurements and evaluative ratings produced in surveys, tests, and quality assessments.

The main types are nominal, ordinal, interval, and ratio scales. Nominal scales categorize data without any inherent order (for example, blood type or gender). Ordinal scales impose a rank order but not equal intervals (for example, education level or Likert-style survey responses). Interval scales have ordered values with equal intervals but no true zero (for example, Celsius temperature). Ratio scales possess a meaningful zero and allow comparison by ratio (for example, height or weight).

In practice mittaasteikot are used across education, psychology, market research, and engineering to design instruments and analyze results. The scale chosen influences permissible statistics and interpretations: nominal and ordinal data are often analyzed with nonparametric methods, while interval and ratio data support a wider range of parametric analyses. Researchers sometimes treat ordinal data as interval for convenience, a practice that is debated.

Related concepts include metrology, psychometrics, and the broader study of data scales and measurement validity.