pub trait Regression {
// Required methods
fn coefficients(&self) -> Vec<Box<dyn StatisticalEstimate<f64, f64>>>;
fn estimate_function(
&self,
) -> Box<dyn StatisticalEstimate<LinearEstimatorClosure, DMatrix<f64>>>;
fn residuals(&self) -> DMatrix<f64>;
fn predictions(
&self,
) -> Box<dyn StatisticalEstimate<DMatrix<f64>, DMatrix<f64>>>;
fn variance_covariance_matrix(&self) -> DMatrix<f64>;
fn determination(&self) -> Box<dyn Statistic>;
}