Research Article| Volume 17, ISSUE 6, P571-579, June 1995

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V. Comparison of Means

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      The t test is used commonly by researchers to test hypotheses involving data that are normally distributed and can be summarized by means and standard deviations. The paired t test is used to compare two paired observations on the same individual, or on matched individuals. The unpaired t test is used to compare the means of two independent samples. Although these tests are now easily performed using statistical programmes available for personal computers, it is important to understand the concepts involved in the calculations. Misuse of the test will often lead to false conclusions.


      Le test t est utilisé couramment par les chercheurs pour tester des hypothèses sur des données normalement distribuées pouvant être résumées au moyen de moyennes et d’écarts types. Le test t apparié permet de comparer deux observations portant sur le même individu ou les observations portant sur deux individus assortis. Le test t non apparié est utilisé pour comparer les moyennes de deux échantillons indépendants. Bien que ces tests soient maintenant d’utilisation simple grâce aux programmes de statistiques des ordinateurs individuels, il est important de comprendre les notions qui interviennent dans les calculs. L’utilisation erronée de ces tests aboutit souvent à des conclusions fausses.

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      Suggested Reading

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