Regression Analysis, R Squared, Pseudo R Squared, Adjusted R Squared, Deviance.
nonlinear model + Deviance explained by the fitted nonlinear model. Notation-wise: The Deviance identity for nonlinear regression models (Image by Author) Where: D(y, y_mean) = Deviance of the Intercept-only model D(y, y_pred) = Deviance of the fitted nonlinear model D(y_pred, y_mean) = Deviance