Which statement best describes simple regression?

Which statement best describes simple regression?

• A. It involves multiple predictor variables.
• B. It is nonparametric.
• C. It predicts Y from a single predictor X.
• D. It does not include an intercept.

Answer: (C)

Simple regression is about predicting a dependent variable Y from a single predictor X using a straight-line relationship. The “simple” in simple regression means there is just one predictor variable, so the model fits a line described by Y ≈ β0 + β1X. This makes it a parametric approach, since it assumes a specific form (a line) and estimates the parameters β0 and β1 from the data. There is usually an intercept term β0, which is the predicted Y when X is zero; therefore saying there’s no intercept isn’t accurate for the standard form. It’s not nonparametric, and it’s not about using multiple predictors—that would be multiple regression.

Simple regression is about predicting a dependent variable Y from a single predictor X using a straight-line relationship. The “simple” in simple regression means there is just one predictor variable, so the model fits a line described by Y ≈ β0 + β1X. This makes it a parametric approach, since it assumes a specific form (a line) and estimates the parameters β0 and β1 from the data. There is usually an intercept term β0, which is the predicted Y when X is zero; therefore saying there’s no intercept isn’t accurate for the standard form. It’s not nonparametric, and it’s not about using multiple predictors—that would be multiple regression.