Three tests for more than two dependent samples are the Friedman, Kendall’s W, and Cochran’s Q tests.
The Friedman test serves as the significance test for more than two dependent samples. It is also known as the Friedman two-way analysis of variance. Researchers use it to test the null hypothesis. They use it to check if the size of ‘k’ dependent samples differs from the population. In SPSS, select “Nonparametric Tests” from the Analyze menu, then “K Related Samples,” choose “Test Variables,” and select “Friedman” under test type. The Friedman test statistic follows a chi-square distribution with (k – 1) degrees of freedom, and we calculate it using the following formula:
Chi-squareFriedman = (* – 3n(k + 1).
We refer to Kendall’s W Test as the normalization of the Friedman statistic. We use Kendall’s W to assess the trend of agreement among the respondents. In SPSS, we perform Kendall’s W Test by selecting “Nonparametric Tests” from the Analyze menu and then clicking on “K Related Samples.” After this, select “Test Variables,” and then under the option test type, select “Kendall’s W.” Kendall’s W ranges from 0 to 1. The value ‘1’ refers to the complete agreement among/between the raters, and value ‘0’ refers to the complete.
We use the Cochran’s Q test to determine whether the part of a given variable is the same across multiple dependent samples. In SPSS, we perform the Cochran’s Q test by selecting “Nonparametric Tests” from the Analyze menu and then selecting “K Related Samples.” After this, select “Test Variables,” and then under test type, select “Cochran’s Q.” Cochran’s Q is a chi square statistic which is an extension of McNemar test.
Assumptions:
We assume random sampling in all significance tests for more than two dependent samples.
The three tests are non-parametric; they do not assume normal distribution.
The three tests in the significance tests for more than two dependent samples permit multiple dependent samples.
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Related Pages:
To Reference this Page: Statistics Solutions. (2013). Friedman Test, Kendall’s W, Cochran’s Q: Significance Tests for More Thank Two Dependent Samples . Retrieved from https://www.statisticssolutions.com/free-resources/directory-of-statistical-analyses/significance-tests-for-more-than-two-dependent-samples-friedman-test-kendalls-w-cochrans-q/