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Can you do a paired t test on categorical data?
This is the equivalent of the paired samples t-test, but allows for two or more levels of the categorical variable. This tests whether the mean of the dependent variable differs by the categorical variable. We have an example data set called rb4, which is used in Kirk’s book Experimental Design.
Can you use chi-square for paired data?
Can Chi-squared or Fisher’s tests be used if your data is categorical? When data are paired and the outcome of interest is a proportion, the McNemar Test is used to evaluate hypotheses about the data. The McNemar test is only used for paired nominal data.
How many categorical variables do you need for the chi square test?
At minimum, your data should include two categorical variables (represented in columns) that will be used in the analysis. The categorical variables must include at least two groups. Your data may be formatted in either of the following ways: Cases represent subjects, and each subject appears once in the dataset.
Which is more powerful a paired test or a chi square test?
Paired t-tests are more powerful than between subjects because although they’re essentially testing the same hypothesis about the equivalence of two means, a paired test is able to do it with a lot smaller error variance. But McNemar and Chi-square are really testing two different hypotheses. Ah, that makes sense.
How are data categories classified in a contingency table?
A contingency table (also known as a cross-tabulation, crosstab, or two-way table) is an arrangement in which data is classified according to two categorical variables. The categories for one variable appear in the rows, and the categories for the other variable appear in columns.
How are data organized in a matched pairs problem?
In general, in every matched pairs problem, our data consist of 2 samples which are organized in n pairs: We reduce the two samples to only one by calculating the difference between the two observations for each pair. For example, think of Sample 1 as “before” and Sample 2 as “after”.