function estimation = moindres_carres_ecretes(D_app,beta_0,beta_d,d,lambda)

    X = D_app(1,:)';
    Y = D_app(2,:)';

    [A, B, beta_chapeau] = moindres_carres(D_app, beta_0, beta_d, d);

    slope = (beta_d - beta_0) / (X(length(X)) - X(1));
    beta_barre = slope*X + beta_0;

    C = B - A * beta_chapeau';

    delta_chapeau = (A' * A + lambda * eye(d-1)) \ A' * C

end