The UIS Glossary includes statistical terms related to education, science, technology and innovation, culture, and communication & information . Some of the entries contain translations in one or more of the following languages: Arabic, English, French and Spanish. Other entries provide more detailed information, such as definitions, calculation formulas for indicators and sources. Indicators are marked with an asterisk (*).

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Volunteer sampling

Sample units volunteer their services for the study. This is a non-probability sampling method.

Échantillonnage volontaire

Unités d'échantillonnage offrent volontairement leurs participation à l'étude en question.

Muestreo voluntario

Unidades de muestras ofrecen sus servicios al estudio en forma voluntaria. Este el método no probabilístico de muestreo.