“…These splines have been used and developed widely in several cases by many researchers. For example, Liu et al [14] and Gao and Shi [15] used M-type splines for analyzing the variance in correlated data, and for estimating regression functions of nonparametric and semiparametric regression models, respectively; Chamidah et al [16] used truncated splines to estimate mean arterial pressure for prediction purposes, Chamidah et al [17] and Lestari et al [18] developed truncated spline and smoothing spline estimators, respectively, for estimating semiparametric regression models and determining the asymptotic properties of the estimator; Tirosh et al [19], Irizarry [20], Adams et al [21,22], Lee [23], and Maharani and Saputro [24] discussed smoothing spline for problems of analyzing fractal-like signals, minimizing risk estimate, modeling ARMA observations and estimating smoothing parameter, selection smoothing parameter using simulation data, and determining GCV criterion, respectively; Wang [13], Wang and Ke [25], Gu [26], and Sun et al [27] discussed smoothing splines in ANOVA models; Wang et al [28] applied a bivariate smoothing spline to data of cortisol and ACTH hormones; Lu et al [29] used a penalized spline for analyzing current status data; Berry and Helwig [30] compared tuning methods for penalized splines; Islamiyati et al [31,32] developed a least square spline for estimating two responses of non-parametric regression models and discussed linear spline in the modeling of blood sugar; and Kirkby et al [33] estimated nonparametric density using B-Spline. Additionally, Osmani et al [34] estimated the coefficient of a rates model using kernel and spline estimators.…”