Question

I know that "sleeping hours" is a numerical variable, but what about variables
such as a.0-3 hours b.3-6 hours c.6-9 hours ???? is this categorical variables?

Answer 1

No this isn't categorical variable because categorical variable takes the values that are either name or labels. But here we have the numerical values. We can say these type of data interval variable. In interval variable the variable takes the value in between the minimum and maximum of that interval. So from the given data we can explain that sleeping hours for somebody is between 0hrs to 3 hrs, 3hrs to 6 hrs, 6hrs to 9 hrs respectively. Hence it can be called interval variable.