What role does an independent variable play in a regression function?

In a regression function, the independent variable plays a critical role in determining the output value, which is the dependent variable. The independent variable is the input that influences the outcome of the regression analysis. It is the factor that is manipulated or changed to observe its effect on the dependent variable.

For example, if you are examining how house prices depend on square footage, the square footage serves as the independent variable, and the house price is the dependent variable. Changes in the size of the house will lead to changes in the price, demonstrating the cause-and-effect relationship that regression analysis aims to quantify.

While it could be tempting to identify the main factor being predicted or assume that the independent variable might be a constant, these descriptions do not capture the essence of how independent variables function in regression analysis. They are central to establishing the relationship between the input and the output.