Dynamic Display of Changing Posterior in Bayesian Survival Analysis: The Software

We consider the problem of estimating an unknown distribution function in the presence of censoring under the conditions that a parametric model is believed to hold approximately. We use a Bayesian approach, in which the prior on is a mixture of Dirichlet distributions. A hyperparameter of the prior determines the extent to which this prior concentrates its mass around the parametric family. A Gibbs sampling algorithm to estimate the posterior distributions of the parameters of interest is reviewed. An importance sampling scheme enables us to use the output of the Gibbs sampler to very quickly recalculate the posterior when we change the hyperparameters of the prior. The calculations can be done sufficiently fast to enable the dynamic display of the changing posterior as the prior hyperparameters are varied. This paper provides a literate program completely documenting the code for performing the dynamic graphics.

Meeting Dietary Food Groups Serving’s Requirements of Food Guide Pyramid among Jordanian University Students

The current study was conducted in the Jordan University of Science and Technology (JUST), Northern of Jordan. The aim of this study is to determine the consumption from food groups compared with the food guide pyramid among University students living away from their homes and to examine how the economic status of the study sample and the influence it has on spent on food.  The study targeted male students known to live away from their parents, where a convenient sample of 370 male students chosen randomly from different majors and academic years and with different socio-economic backgrounds. Participants were interviewed by trained nutritionists where the actual intakes number of servings from each food groups was recorded. The results of the study showed that 75.7% of the study subjects who lived away from home; they reside in Jordan, while 24.3% of the students’ parents were living outside Jordan. In addition, most of outside students fit in the highest financial income per month category comprising three-quarters those in the “more than 201 dinar” category. Regarding the number of servings consumed from each group, 44% of the study sample consume less than the minimum recommended servings for the dairy group; most participants don’t meet the recommendations for meat and meat substitutes group by a percentage of 38.9%; only 11.1% meet daily recommendations from vegetables group; 46% of students do not meet the minimum recommended number of servings of fruits group and most of the study sample (43.8%) meet recommended number of servings from grain group.  It is recommended to meet daily recommendations of servings from the food groups (dairy, meat, grains, fruits and vegetables); specifically to increase fruits intake; for it’s rich content of nutrients not available from any other sources. Further studies are suggested to evaluate the food intake with different dietary evaluation tools. Key words: Food Groups, Serving, Food Guide Pyramid, Residency, University Students, Jordan

Prevalence of Obesity and Perceptions of Body Weight among University Students: Evidence from Jordan

This study was conducted to investigate the effect of measure the prevalence of obesity among university population in Jordan University of Science and Technology (JUST) University, Northern Jordan. A cross-sectional survey of (370) university male students were recruited from different majors and academic years. They were asked to answer questions concerning ; perception of their body weight and weight changes after leaving home; Participants’ desire to reduce their body weight; the reasons that drive this desire and means used for weight reduction. Weights, heights and body mass index (BMI) were measured. The prevalence of the BMI categories in the sample were: 50% of the study sample is overweight making up the majority, participants with a normal BMI are 28%, 11.1% are underweight and 11% of participants suffer from obesity. Regarding to the participants’ perception of their body weight and weight changes, the study results showed that 74.8% of the students in the study sample are in the normal or overweight categories, 22% are underweight and 3% are obese. The extent of weight change due to living away from home was also reported, where 50% confirmed a slight loss in their weight, 5% had a significant increase and 12% experienced no changes in their body weight. 67% of the total participants had a desire to lose weight where the rest of the 33% had no desire to lose weight. In conclusion, overweight and obesity do exist in the university students and this maybe a reflection of the lifestyle; dietary habits and pattern of living in university. Further research is needed to investigate the dietary habits and lifestyle behaviors of the university students. Keywords: Obesity, Overweight, Perceptions of body weight, University students, JUST University, Jorda

Dietary and Lifestyle Behaviors of the University Students Living Away from Their Home: A Cross-Sectional Study

Dietary behaviors of the young population are affected by numerous factors. University study period also influences the lifestyle of students, including diet. The objective of this study was to explore dietary and lifestyle behaviors of Jordan University of Science and Technology (J.U.S.T.) students living away from their home. A convenient sample of 370 male students was recruited from different majors and academic years and with different socio-economic backgrounds. The sample size was calculated proportionally to the total number of university students. Participants filled out a self-reported questionnaire (included questions on eating and physical activity habits). Most participants spend around 51% of their financial income on food items. Statistical analysis of the available data shows that the general health in majority of the study sample is good. The psychological status of the participants has a significant direct effect on food intake. Results show that 71% of the study sample are not interested nor affected at all by books, internet, videos and magazines that portray food. In addition, fresh foods are predominantly consumed in both breakfast and lunch, while processed foods are more common in the dinner between 71% participants. Furthermore, consumption of snacks with discretionary calories is much higher that than of healthy snacks like fruits. It is recommended to plan and implement a nutritional intervention, extension and education programs which allow university students to improve their nutritional knowledge. Keywords: Dietary behaviors, Lifestyle, University students, Diet, Cross-sectional study, J.U.S.T., Jordan

Dynamic Display of Changing Posterior in Bayesian Survival Analysis: The Software

We consider the problem of estimating an unknown distribution function in the presence of censoring under the conditions that a parametric model is believed to hold approximately. We use a Bayesian approach, in which the prior on is a mixture of Dirichlet distributions. A hyperparameter of the prior determines the extent to which this prior concentrates its mass around the parametric family. A Gibbs sampling algorithm to estimate the posterior distributions of the parameters of interest is reviewed. An importance sampling scheme enables us to use the output of the Gibbs sampler to very quickly recalculate the posterior when we change the hyperparameters of the prior. The calculations can be done sufficiently fast to enable the dynamic display of the changing posterior as the prior hyperparameters are varied. This paper provides a literate program completely documenting the code for performing the dynamic graphics. July 2, 1998 bsa.nw 4 1 Copyright We begin with our usual copyright. ..

Analisis Tingkat Produksi Padi dan Perhitungan Logistik Pangan Berdasarkan Metode Evi (Enhanced Vegetation Index) dan Ndvi (Normalized Difference Vegetation Index) Menggunakan Citra Sentinel-2 Tahun 2016 (Studi Kasus : Kabupaten Klaten, Jawa Tengah)

Tanaman padi merupakan salah satu tanaman yang menghasilkan bahan makanan pokok penting bagi sebagian besar masyarakat Indonesia, yakni beras. Tanaman padi merupakan sektor utama pangan yang menjadi perhatian khusus karena ketersediaannya sangat berpengaruh penting mengingat tingginya pertumbuhan penduduk yang terjadi saat ini. Indonesia memiliki banyak daerah yang menjadi lumbung padi di Indonesia dan memiliki kualitas beras yang baik, salah satunya adalah Kabupaten Klaten.Penginderaan jauh merupakan teknologi yang cocok diaplikasikan untuk mengestimasi produksi padi.di Kabupaten Klaten. Hal tersebut terkait dengan keunggulan sensor yang sensitif terhadap tanaman padi, mencakup wilayah yang sangat luas, dan mengetahui fase tumbuh tanaman padi serta pola tanam padi lebih baik dan cepat. Penggunaan citra satelit Sentinel-2 yang memiliki resolusi spasial yang tinggi disertai dengan algoritma indeks vegetasi EVI (Enhanced Vegetation Index) dan NDVI (Normalized Difference Vegetation Index) sangat efektif dan efisien diterapkan untuk klasifikasi fase padi dari masa tanam hingga masa panen serta mengestimasi produktivitas dan produksi padi. Estimasi produksi padi menjadi acuan dalam penentuan nilai logistik pangan yakni ketersediaan padi tersebut mencukupi atau tidak konsumsi masyarakat Kabupaten Klaten selama satu tahun. Penelitian ini menghasilkan peta fase tumbuh padi algoritma EVI dan NDVI, nilai estimasi produksi dan nilai logistik pangan tahun 2016. Berdasarkan peta fase tumbuh algoritma EVI dan NDVI, fase generatif lebih mendominasi bulan April dan bulan Oktober sedangan fase vegetatif lebih mendominasi bulan Maret dan bulan Desember. Nilai estimasi produksi padi hasil pengolahan tahun 2016 sebesar 782801.589 ton dalam satu tahun dan nilai logistik pangan tahun 2016 sebesar (+) 649291,329 ton. Berdasarkan nilai estimasi produksi padi dan nilai logistik pangan tahun 2016 mengartikan bahwa produksi padi dapat mencukupi konsumsi masyarakat Kabupaten Klaten tahun 201

Stratified Extreme Ranked Set Sample With Application To Ratio Estimators

Stratified extreme ranked set sample (SERSS) is introduced. The performance of the combined and separate ratio estimates using SERSS is investigated. Theoretical and simulation study are presented. Results indicate that using SERSS for estimating the ratios is more efficient than using stratified simple random sample (SSRS) and simple random sample (SRS). In some cases it is more efficient than ranked set sample (RSS) and stratified ranked set sample (SRSS), when the underlying distribution is symmetric. An application to real data on the bilirubin level in jaundice babies is introduced to illustrate the method

Optical Emission Characterization of High-Power Hall Thruster Wear

Optical emission spectroscopy is employed to correlate BN insulator erosion with high-power operation of the NASA 300M Hall-effect thruster. Actinometry leveraging excited xenon states is used to normalize the emission spectra of ground state boron as a function of thruster operating condition. Trends in the strength of the boron signal are correlated with thruster power, discharge voltage, discharge current and magnetic field strength. The boron signals are shown to trend with discharge current and show weak dependence on discharge voltage. The trends are consistent with data previously collected on the NASA 300M and NASA 457M thrusters but are different from conventional wisdom