vastaajan

Vastaaja is a Finnish noun meaning “respondent” or “answerer.” It refers to a person who provides information by answering questions in a survey, questionnaire, interview, or other data-collection method. The genitive singular form vastaajan is used to indicate possession, as in “vastaajan tausta” (the respondent’s background) or “vastaajan vastaus” (the respondent’s answer). The word forms include vastaajat (nominative plural), vastaajien (genitive plural), and vastaajaa (partitive singular). The etymology traces to the verb vastata, “to answer,” with the agent noun suffix -aja, yielding “one who answers.”

In research and public statistics, vastaajat are the units from whom data are collected. Their responses form the basis for estimating opinions, behaviors, or characteristics of a population. Sampling design, response rates, non-response bias, and questionnaire quality influence the reliability of results. Anonymization and data protection are standard considerations when handling respondent data.

More generally, the term appears in academic writing, market research reports, and media coverage to refer to those who provided information in a study. Although the concept is language-specific to Finnish, equivalent terms exist in many languages, such as respondent, interviewee, or participant.