Dependent and independent variables
lastmod 2018-08-22created 2018-07-245 edits
Variables used in experiments or modeling can be classified as independent variables, dependent variables, or other.
- Independent variables represent inputs or causes,
- and dependent variables represent outputs or effects.
Variables observed for various other reasons are called other variables.
Statistics terminology
An independent variable goes by various terms such as predictor variable, regressor, controlled variable, manipulated variable, exposure variable, and risk factor, and in machine learning or pattern recognition it is also called a feature. It is also simply called an input variable.
An independent variable is also called an explanatory variable. This term is preferred only when the quantities treated as independent variables are not statistically independent.
Example
\(y = f(x)\) where:
- X is the input variable
- Y is the dependent variable