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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Subset of individuals from a specific population, formed according to a selection process (with or without replacement and at random or not). A sample that is formed through the random selection of individuals based on known probabilities is called a random or probability sample. A non-random sample is formed on the basis of a subjective method of selection.


Sous-ensemble d’individus d’une population spécifique, formé conformément à un processus de sélection (avec ou sans remplacement et de façon aléatoire ou non). Un échantillon formé par une sélection aléatoire d’individus sur la base de probabilités connues est qualifié d’échantillon aléatoire ou probabiliste. Un échantillon non aléatoire est formé sur la base d’une méthode de sélection subjective.


Sub-conjunto de personas de una población específica resultado de un proceso de selección (con o sin reemplazos y realizado en forma aleatoria o no aleatoria). Una muestra formada a través de la selección aleatoria de personas sobre la base de probabilidades conocidas se denomina muestra probabilística. Una muestra no aleatoria es aquella formada en base a un criterio subjetivo de selección.