Judul: Comparison of Generalized Additive Models and Multivariate Adaptive Regression Splines (Case Study: Modeling of Grade Point Average of IPB and STAIN Purwokerto Students)
Abstrak: Regression analysis is used to capture influences of independent variables to dependent ones. It can be done in two ways, parametric and nonparametric approach. The parametric approach needs assumptions, while nonparametric approach is more flexible than the parametric one. The nonparametric approach used in this research is Generalized Additive Models (GAM) and Multivariate Adaptive Regression Splines (MARS). Essentially, GAM and MARS can accommodate nonlinearity data.
Keyword: Nonparametric regression, Generalized Additive Models, Multivariate Adaptive Regression Splines

Judul: Identifikasi Faktor-Faktor yang Memengaruhi Indeks Prestasi Kumulatif (IPK) Menggunakan Regresi Logistik Biner dan Multinomial
Abstrak: Grade Point Average (GPA) is a measure of student academic achievement at a college education. The objective of this study is to identify factors that influence a student GPA of the Mathematics Department of IPB in generation 2009–2011 using binary and multinomial logistic regression. Based on binary logistic regression, the factor of student GPA is duration of study. Meanwhile based on multinomial logistic regression, the factors of student GPA are mother employment status, expenditure per month in addition to the cost of living and academic, and extra hours of study such as tutoring. This shows that student classification based on their GPA determines the conclusion
Keyword: binary regression logistic, grade point average (GPA), multinomial regression logistic.

Judul: Hybrid solar cells of ZnO nanoparticles/chlorophyll was modified metal ions (Zn2+ and Cu2+ )
Abstrak: Zinc Oxide (ZnO) is a n-type semiconductor with a wide the energy band (Band Gap) is 3.37 eV at room temperature and 3.34 eV at low temperature with a large exiton binding energy is 60 meV. ZnO has been synthesized by hydrothermal method, resulting in a decrease in particle size over the duration of the hydrothermal changes. Crystallographic structure of ZnO were characterized using XRD, has shown the characteristic pattern of a hexagonal wurtzite structure, the crystallite size increases to changes in particle size. Changes in particle size has also led to a change in the absorption peak of ZnO as has been demonstrated posted under test using the optical properties of UV-Vis spectrophotometer. Changes of this uptake has also led to changes in the energy band gap, which increases its band gap energy of the particle size. In electronic applications, especially in solar cells. Chlorophyll is considered less effective, because of their very nature are easily degraded as a result of several reactions which are acid, lighting and temperature. The results of the stability test using a halogen lamp 34 W/m2 for 5 hours, that the substitution of chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form more stable than natural chlorophyll. The characterization of the optical properties, the combination of ZnO / chlorophyll in the form of hybrid films has led to a shift in the absorption region of ZnO becomes more widely from the UV to Visible. ZnO/chlorophyll has absorption range of 350-515 nm, ZnO / Zn-feofitin 332-401 nm and 332-632 nm for Cu-feofitin. The combination of ZnO/chlorophyll and CuSCN as a solid electrolite in hybrid solar cell, a modified chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form a more stable I-V curve. It is characterized by its fill factor value greater than natural chlorophyll. Nevertheless, solar cells with natural chlorophyll has been able to produce higher efficiency values of chlorophyll were substituted.
Keyword: Hydrothermal, ZnO/Chlorophyll modified, Hybrid Solar Cell