Fig. 7

Coefficient progression with LASSO. a As the parameters shrink, the mean-squared error flattens at first and increases rapidly after four parameters are retained. b The change in the coefficient of each parameter as the parameters shrink. The first dotted line means that we used the λ at which the minimal mean squared error (MSE) is achieved (lambda.min) to select the optional model. The second dotted line means that we used the largest λ at which the MSE is within one standard error of the minimal MSE (lambda.1se) to select the optional model. The latter was selected as the final model in this study