Judul: Analysis of production function and technical efficiency of soybean farms in Indonesia
Abstrak: Soybean is a main source of protein for Indonesian. Demand for soybean increased rapidly over the years, but the production grow slowly. In such situation, it is not surprising that Indonesia always imports large numbers of soybean in order to meet the national consumption. To overcome these problems, the Indonesian government has targeted to increase soybean production to achieve self-sufficiency in 2014. Increase in soybean production can be performed by increasing the number of factor production used. In soybean farming, the factors of land, seed, fertilizer, pesticides, and labor are considered as factors affecting the soybean production. Soybean production not only determined by factors production used but also by the farmers technical efficiency levels. There are three objectives in this study: (1) to identify factors that influence the production of soybean production in Java and outside Java, (2) to determine the technical efficiency of soybean farmer in Java and outside Java, and (3) to identify the factors affecting technical efficiency in the Java and outside Java. This study uses cross section data obtained from the farmer cost structure survey held by BPS in 2011. The analytical tool used to determine the factors affecting the production and measure farmers' technical efficiency is the stochastic frontier production function. The results of analysis show that soybean production in Java influenced by land, seed, KCl fertilizer, pesticides, and labor. Factors affecting production outside Java are land, seed, urea fertilizer, TSP/SP36 fertilizer, KCl fertilizer, pesticides, and labor. The average value of technical efficiency of soybean farmers in Java is 0.41. Farmer age, education level, seed aid, the use of tractors, and the use of quality seeds proved to have an influence on the technical inefficiency in Java. The average value of technical efficiency of soybean farmers outside Java is 0.6. Factors affecting the level of technical inefficiency outside Java are farmer age, education level, seed aid, fertilizer aid, counseling, and the use of quality seeds. Efforts that can be suggested to increase soybean production in Java are promoting agricultural intensification strategy. This is because the elasticity of seed, KCl fertilizer, and labor in Java is greater than outside Java. Efforts that can be suggested to increase soybean production outside Java are promoting agricultural ekstensification strategy. This is because the elasticity for land outside Java is greater than Java. Technical efficiency of farmers in Java can be improved by reducing the seed aid, introducing land preparation technology using tractors, and also increasing the use of quality seeds. Outside Java, technical efficiency improvement can be reached by reducing the seed aid, increasing fertilizer aid, optimizing counseling, and also increasing the use of quality seeds.
Keyword: soybean, production function, stochastic frontier, technical efficiency

Judul: Efisiensi Teknis Produksi Usahatani Tebu Jawa – Luar  Jawa: Pendekatan Stochastic Frontier Analysis
Abstrak: Sugar cane is the main ingredient in the production of sugar which is consumed by the majority of Indonesian people. This commodity has a vital role in various aspects such as economic, social, and political. In providing the need for sugar, there needs to be good planning so that various upheavals do not occur. Sugarcane production produced by farmers for a decade has significantly increased to reach an average growth of 0.84 percent. Meanwhile, the sugarcane harvested area, which is the main factor in production, has dramatically decreased with an average growth of -0.05 percent since 2012. The decreasing harvested area is a concern in maintaining Indonesia's sugarcane production. However, the Sugar Factory (PG) requires a large harvest area for sugar production, accounting for 20 thousand ha to produce 10 thousand tons of sugar per day, thus causing a critical concern in population growth. In increasing production with continuously decreasing land conditions, it is necessary to use the Intensification method. The island of Java is dominating sugarcane production in Indonesia, which in the long term, it will no longer be able to contribute to production due to the conversion of agricultural land to non agricultural use and the level of technical efficiency in the current sugarcane farming production which has been almost well-developed. This condition is an alternative for the development of more agricultural areas outside Java Island. There are 10 provinces outside Java, namely Lampung, South Sumatra, Aceh, West Nusa Tenggara, Gorontalo, East Nusa Tenggara, North Sumatra, Bali, South Sulawesi and Southeast Sulawesi and 4 provinces in Java, namely East Java, Central Java, West Java, and DI Yogyakarta which have become targeted areas for the development of sugar cane based on PERMENTAN NO. 18 of 2018. This study aims to analyze and discuss the level of technical efficiency of sugar cane farming in Java and outside Java. The performance of sugarcane farmers in Java - Outside Java is seen from the level of technical efficiency which can indirectly describe the performance of sugarcane farmers in the development of sugarcane areas. The data used in this study is secondary data in the form of cross sections. The research data comes from the results of the 2014 Sugar Cane Business Household Survey which is part of the results of the 2013 Central Statistics Agency Agricultural Census with code ST2013-SKB.S. The research data were analyzed using a technical inefficiency model on the Cobb-Douglas stochastic frontier production function to see the characteristic and socioeconomic factors that influence inefficiency. Based on the research results in achieving maximum output, land, seeds with nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, and labor have a significant effect on Java Island, whereas the harvest area, seeds, and fertilizer elements of phosphorus become crucial factors outside Java Island. Among the variables concerned, land has the highest coefficient for Java Island. It shows that the increase in harvested area in Java is 4 times greater in producing production compared to outside Java. Increased harvested area is closely related to extensification. This is more likely to be done outside of Java. In this case,
Keyword: institution, stochastic frontier production function, sugarcane area, sugarcane farming, technical efficiency

Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf