1. simple linear regression equation: a statistical model in which the expected value of a response variable is conditional on a single predictor variable and the model is linear in its parameters 2. multiple linear regression equation: a statistical model in which the expected value of a response variable is conditional on one or more predictor variables and the model is linear in its parameters 3. nonlinear regression equation: a statistical model in which the expected value of a response variable is conditional on one or more predictor variables and the model is nonlinear in its parameters —see generalized linear modelsThis definition last updated 07/12/2008