Abdul-Kareem Fayadh N, Jaafar Hussain W. Comparison between the Local Polynomial Kernel Method and cubic spline to Estimating Time-Varying Coefficients Model. wjps [Internet]. 2022 Dec. 24 [cited 2025 Dec. 26];1(3):105-14. Available from: https://wjps.uowasit.edu.iq/index.php/wjps/article/view/71