Judul: Analysis of Factors Influencing Interests of Farmer Families Youth to Work in Sweet Potato Farming (Case Study: Jatirogo District, Tuban Regency)
Abstrak: Sentra produksi ubi jalar terbesar di Kabupaten Tuban yaitu di Kecamatan Jatirogo. Ubi jalar menjadi komoditas penting sebagai sumber pendapatan petani. Usia petani di Kecamatan Jatirogo didominasi oleh petani yang berusia tua, hal ini dikarenakan rendahnya minat pemuda untuk melakukan usahatani ubi jalar. Penelitian ini bertujuan untuk: (1) menganalisis pendapatan usahatani ubi jalar di Kecamatan Jatirogo, (2) mengidentifikasi persepsi petani dan pemuda keluarga tani terhadap usahatani ubi jalar Kecamatan Jatirogo, (3) menganalisis faktor-faktor yang memengaruhi minat pemuda keluarga tani untuk bekerja di usahatani ubi jalar di Kecamatan Jatirogo. Metode analisis data menggunakan analisis pendapatan, skala likert dan regresi logistik biner. Hasil penelitian menunjukkan nilai R/C rasio lebih dari satu artinya usahatani ubi jalar menguntungkan. Persepsi petani terhadap pekerjaan di usahatani ubi jalar secara umum adalah setuju namun tidak setuju terhadap aspek ekonomi dan kestabilan harga jual ubi jalar. Hasil persepsi pemuda keluarga tani ubi jalar secara keseluruhan adalah setuju namun kurang setuju terhadap aspek pendapatan dan tingkat konsumsi ubi jalar dalam rumah tangga. Faktor-faktor yang berpengaruh secara positif terhadap minat pemuda keluarga tani untuk bekerja di usahatani ubi jalar adalah jenis kelamin, status penikahan, pengalaman usahatani dan tingkat pendapatan pertanian keluarga pemuda., The biggest sweet potato production center in Tuban Regency is Jatirogo District. Sweet potato is an important commodity as a source of income for farmers. The age of farmers in Jatirogo District is dominated by older farmers, this is due to the low interest of youth to do sweet potato farming. This study aims to: (1) analyze the income of sweet potato farming in Jatirogo District, (2) identify the perceptions of farmers and farmer families youth towards sweet potato farming in Jatirogo District, (3) analysis of factors influencing interest of farmer families youth to work in sweet potato farming in Jatirogo District. Data analysis methods used income analysis, likert scale and binary logistic regression. The result of the study shows that the R/C ratio was more than one, meaning sweet potato farming was profitable. Farmers’ perceptions of work in sweet potato farming in general are agree but disagree with aspect of economics and the stability sweet potato selling prices. The result of the perception of the youth of sweet potato farming families as a whole agree but do not agree with the income aspect and the level of consumption sweet potato in the household. Factors that have a positive effect on the interest of farmer families youth to work in sweet potato farming are gender, marital status, farming experience and the level of agricultural income of youth families.
Keyword: binary logistic regression, income analysis, likert scale, perception, R/C ratio

Judul: Analysis of Technical Production and Income from Sweet Potato Farming in Bandorasa Wetan Village, Cilimus Sub-district, Kuningan Regency
Abstrak: Desa Bandorasa Wetan merupakan salah satu produsen ubi jalar terbesar di Kabupaten Kuningan yang juga menjadi sentra pengolahan ubi jalar. Persoalan yang dihadapi petani ubi jalar dalam mengelola usahatani adalah bagaimana mengalokasikan faktor-faktor produksi secara tepat agar dapat memaksimumkan produksi sehingga akan meningkatkan pendapatan. Oleh karena itu, tujuan dari penelitian ini yaitu untuk menganalisis usahatani ubi jalar di Desa Bandorasa Wetan yang berkaitan dengan (1) faktor-faktor yang memengaruhi produktivitas (2) efisiensi produksi (3) pendapatan petani (4) hubungan efisiensi teknis dan pendapatan petani. Metode yang digunakan dalam penelitian ini adalah regresi linear berganda dengan metode Maximum Likelihood Estimation (MLE), analisis efisiensi teknis dengan metode Stochastic Frontier Analysis (SFA), analisis pendapatan dengan menggunakan R/C ratio, serta analisis hubungan efisiensi teknis dan pendapatan dengan uji Rank Spearman. Hasil penelitian menunjukkan bahwa pupuk urea, pupuk phonska, dan pupuk TSP berpengaruh positif dan signifikan terhadap produksi ubi jalar. Nilai rata-rata efisiensi teknis adalah sebesar 0,91. Pendapatan usahatani ubi jalar lebih besar dari nol dan nilai R/C ratio lebih besar dari satu. Terdapat hubungan positif dan signifikan antara nilai efisiensi teknis dan pendapatan usahatani., Bandorasa Wetan Village is one of the largest sweet potato producers in Kuningan Regency and is also a sweet potato processing center. The problem faced by sweet potato farmers in managing their farming business is how to allocate production factors appropriately in order to maximize production so that it will increase income. Therefore, the aim of this research is to analyze sweet potato farming in Bandorasa Wetan Village in relation to (1) factors that influence productivity (2) production efficiency (3) farmer income (4) the relationship between technical efficiency and farmer income. The method used in this research is multiple linear regression using the Maximum Likelihood Estimation (MLE) method, technical efficiency analysis using the Stochastic Frontier Analysis (SFA) method, income analysis using the R/C ratio, and analysis of the correlation between technical efficiency and income using Rank Spearman test. The research results showed that urea fertilizer, TSP fertilizer, and labor had a positive and significant effect on sweet potato production. The average value of technical efficiency is 0,91. Sweet potato farming income is greater than zero and the R/C ratio value is greater than one. There is a positive and significant relationship between technical efficiency values and farming income.
Keyword: correlation, production factors, productitivy, profit, stochastic frontier

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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