Mann-Whitney U

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This is the non-parametric alternative to an Independent Measures t Test.

Use this statistic when your data is ordinal.

The null hypothesis claims the ranks for each level of the independent variable are equally distributed.

The alternative hypothesis claims the ranks are different for at least one level of the independent variable.

Mann-Whitney U in SPSS

 * 1) Click on 'Analyze' -> 'NonParametric Tests' -> '2 Independent Samples'


 * 1) Move the rankings into the 'Test Variable' box


 * 1) Move the categories into the 'Grouping Variables' box


 * 1) Define your categories


 * 1) Click 'OK'


 * 1) Your output should appear