There are forty cases of insomnia to be used in the study. There are two variables, the therapy and the improvement of sleep. There are two categorical variables in the study.
<h3>What is a variable?</h3>
The term variable refers to something whose value changes. An experiment would always have to variables; the independent variable and the dependent variable. The dependent variable changes when the independent variable is changed.
In this experiment, there are forty cases of insomnia to be used in the study. There are two variables, the therapy and the improvement of sleep. There are two categorical variables in the study.
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