An Example: Age A great example of this is a variable like age. Age is, technically, continuous and ratio. A person’s age does, after all, have a meaningful zero point (birth) and is continuous if you measure it precisely enough. It is meaningful to say that someone (or something) is 7.28 year old.

Like terms are terms that contain the same variables raised to the same power. Only the numerical coefficients are different. In an expression, only like terms can be combined.

In this context, a factor is still a variable, but it refers to a categorical independent variable. So you may have heard of fixed factors and random factors. Like covariates, factors in a linear model can be either control variables or important independent variables. The model uses them the same way in either case.

In context|mathematics|lang=en terms the difference between variable and factor. is that variable is (mathematics) a symbol representing a variable while factor is (mathematics) any of various objects multiplied together to form some whole.

Nominal scale is often used in research surveys and questionnaires where only variable labels hold significance. In this survey question, only the names of the brands are significant for the researcher conducting consumer research. There is no need for any specific order for these brands.

A categorical variable (sometimes called a nominal variable) is one that has two or more categories, but there is no intrinsic ordering to the categories. If the variable has a clear ordering, then that variable would be an ordinal variable, as described below.

As with nominal level variables, ordinal level variables are typically described with frequencies and percentages.

An ordinal variable, is one where the order matters but not the difference between values. An interval variable is a one where the difference between two values is meaningful. The difference between a temperature of 100 degrees and 90 degrees is the same difference as between 90 degrees and 80 degrees.