Judul: A Comparative Study of Beta-Binomial Regression and Williams Methods and their Application to Infant Mortality Data in West Java
Abstrak: Regresi logistik Binom dapat digunakan untuk mengetahui faktor-faktor yang mampu menjelaskan tingkat kematian bayi. Namun, jika data mengandung overdispersi, regresi logistik Binom sudah tidak relevan lagi untuk digunakan. Overdispersi seringkali terjadi pada data biner, seperti pada data kematian bayi. Untuk menangani masalah overdispersi, regresi Beta-Binom dan metode Williams akan dibahas pada penelitian ini. Nilai dugaan parameter yang dihasilkan dengan menggunakan ketiga metode ini tidak berbeda secara signifikan, tetapi nilai galat baku dugaan parameter yang dihasilkan oleh metode regresi logistik Binom cenderung berbias kebawah (underestimate). Hasil simulasi menunjukkan bahwa metode Williams menghasilkan penduga yang lebih baik, ditinjau dari nilai bias dan ragam penduga parameternya dibandingkan dengan regresi Beta-Binom. Selanjutnya, untuk mengindetifikasi faktor-faktor yang mampu menjelaskan tingkat kematian bayi di Jawa Barat perlu diterapkan metode Williams dan regresi Beta-Binom terhadap data kematian bayi di Jawa Barat tahun 2012. Faktor-faktor yang mampu menjelaskan kematian bayi di Jawa Barat yaitu kekayaan rumah tangga, usia ibu, pendidikan ibu dan tempat tinggal.
Keyword: Institut Pertanian Bogor, IPB, Bogor Agricultural University, Beta-Binom regression, Binomial logistic regression, Infant mortality, Overdispersion, Williams methods, Analisis regresi liestik, Overdispersi, Simulasi

Judul: Model Regresi Binomial Negatif Terboboti Geografis untuk Data Kematian Bayi (Studi Kasus 38 Kabupaten/Kota di Jawa Timur)
Abstrak: Negative binomial regression model is used to overcome the overdispersion in Poisson regression model. This model can be used to model the relationship of the infant mortality and the factors incidence. Geographical conditions, socio cultural and economic differ one of location another location causes the factors that influence infant mortality is different locally. Geographically Weighted Negative Binomial Regression (GWNBR) is one of methods for modeling that count data have spatial heterogeneity and overdispersion. The basic idea of this model considers of geography or location as the weight in parameter estimation. The parameter estimator is obtained from Iteratively Newton Raphson method. This research will determine the factors that influence infant mortality. GWNBR model with a weighting adaptive bi-square kernel function classifies regency/city in East Java into 16 groups based on the factors that significantly influence the number of infant mortality. This model is better used to analyze the number of infant mortality in East Java in 2008 due to a smallest deviance value.
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Judul: Characterizations of low alloy steel sae 4422  plated with chromic acid (Cro3)
Abstrak: Characterizations of low alloy steel SAE 4422 plated with chromic acid (CrOrO3) was use Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), RD),Energy Dispersive Analysis of X-Ray (EDAX), Hardness Test and Roughness Test. Microstructures analysis exhibits cracks and grain boundaries microcracks as a characteristics of chrome metal found at plating metal. Perlite and Ferrite as grains of steel found at base metal with grain boundaries around it. Phase analysis of plating metal appropriate to chrome metal with lattice constant (a) is 2.559 Å and phase analysis of base metal appropriate to iron ferrite with lattice constant (a) is 3.318 Å. Both plating and base metal have cubic system. Chemical analysis of plating metal at surface section exhibits that cracks area have highest value of carbon element compare with grains and grains boundaries area. While chemical analysis of base metal at cross section exhibits that perlite have highest value of carbon element compare with ferrite and grain boundaries. The hardness value of plating metal at surface section and cross section are 753 and 637 VHN. While, the hardness value of base metal and interface area at cross section are 205 and 373 VHN. The roughness value at measurement points of chrome surface for as received sample are 0.445 μm. Observation used Optical Microscopy and Scanning Electron Microscopy exhibits surface irregularities combine to form surface texture of plating metal at surface section.
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