Rivas-Ruiz R, Moreno-Palacios J, Talaveraa JO

Language: Spanish
References: 14
Page: 414-419
PDF size: 159.68 Kb.

ABSTRACT

If you want to prove that there are differences between two groups with quantitative variables with non-normal distribution, the Mann-Whitney U test is used. This test is based on rank differences and it is the opposing of the Student t test that use cuantitative variables with a normal distribution. If you want to compare three or more non related groups, the Kruskal-Wallis test is applied. When two related samples are compared Wilcoxon test is the best option (a before and after maneuver comparison), when three related samples are compared, Friedman test is used. These test correspond to the parametric opposing paired t test and Anova, respectively.

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