Ditemukan 2 dokumen yang sesuai dengan query
Ramadhani Fitri
Abstrak :
ABSTRAK
Penaksiran parameter dalam model regresi memiliki dua pendekatan yaitu pendekatan regresi parametrik dan pendekatan regresi nonparametrik. Dalam regresi parametrik bentuk dari kurva hubungan antara variabel respon dan variabel prediktor sudah ditentukan berdasarkan plot data, sedangkan dalam regresi nonparametrik bentuk dari kurva tidak diketahui. Salah satu regresi nonparametrik yang dapat digunakan adalah regresi spline. Regresi spline adalah suatu piecewise polynomial yang dihubungkan oleh titik-titik bersama yang disebut dengan knot. Regresi spline yang menggunakan fungsi basis B Spline disebut dengan regresi B Spline. Pada umumnya estimasi parameter regresi B Spline dilakukan dengan menggunakan metode OLS Ordinary Least Square. Namun, dengan metode OLS akan menyebabkan plot taksiran kurva regresi menjadi fluktuatif apabila pemilihan jumlah knot terlalu banyak. Untuk itu diperlukan suatu tambahan kendala berupa penalty yang didalamnya mengandung smoothing parameter sehingga diperoleh taksiran ideal. Metode estimasi parameter ini dikenal dengan metode PLS Penalized Least Square . Metode PLS dengan penalty yang merupakan integral kuadrat derivatif kedua dari taksiran kurva disebut juga dengan metode o rsquo;sullivan penalized spline. Pada penerapan contoh data, didapat 23 buah knot dan smoothing parameter sebesar 0.68.
ABSTRACT
Parameter estimation of regression model has two approaches, that is parametric and nonparametric regression approach. In parametric regression, the shape of regression curve is determined based on scatterplot of dependent variable vs independent variable, whereas in the nonparametric regression, the shape of the curve is unknown. One of the nonparametric regression is spline regression. Spline regression is piecewise polynomials that connected by the knots. Spline regression using B Spline basis function is B Spline regression. In B spline regression, parameter estimation were fitted by OLS Ordinary Least Square method. However, the OLS method will lead the plot of estimated regression curve be fluctuative when using too much knots. Therefore, it needs additional constraint of penalty that contain smoothing parameter to obtain ideal fit result. This parameter estimation method known as PLS Penalized Least Square method. The estimate PLS method used penalty which is the integral of the square of second derivative of the estimate curve that called o 39 sullivan penalized spline method. In the application of sample data, 23 is used knots and the smoothing parameters is 0.68.
2018
S-Pdf
UI - Skripsi Membership Universitas Indonesia Library
Biebler, Karl-Ernst
Abstrak :
This book presents methods of mathematical modeling from two points of view. Splines provide a general approach while compartment models serve as examples for context related to modeling. The preconditions and characteristics of the developed mathematical models as well as the conditions surrounding data collection and model fit are taken into account. The substantial statements of this book are mathematically proven. The results are ready for application with examples and related program codes given.In this book, splines are algebraically developed such that the reader or user can easily understand and vary the numerical construction of the different kinds of spline functions. The classical compartment models of the pharmacokinetics are systematically analyzed and connected with lifetime distributions. As such, parameter estimation and model fit can be treated statistically with a varied minimum chi-square method. This method is applicable for single kinetics and also allows the calculation of average kinetics.--
Singapore: World Scientific, 2013
511.8 BIE s
Buku Teks Universitas Indonesia Library