Judul: Impact of soybean development policy on performance and soybean consumer and producer welfare in Indonesia
Abstrak: Soybean is one of the major food commodities. It is a food crop that is rich in protein and it has an important role as a plant nutrients protein source that can improve people’s nutrition. Soybean demand that keeps increasing cannot be complied with domestic production, instead of the fact that Indonesia used to be a self-relying soybean country in 1992. However, the production then decreased gradually until 2010, so finally it must be imported greatly. The big amount of imported soybean is enhanced by the change of soybean business, namely the existence of free trade so that there is a lot of imported soybean with reasonable prices. Imported soybean has made farmers reluctant to grow soybean seeds. This is because local soybean is not competitive enough to imported soybean, seen from the viewpoint of price as well as quality. Farmers feel they do not have any incentive for growing soybean, so that their welfare becomes lower, especially when there is no guarantee during the great harvest. The general objective of this research is analyzing impact of soybean development policy on supply, demand changes and soybean consumer and producer welfare in Indonesia. Methods: The survey was conducted on time-series datas between 1981 to 2010. Data were analyzed using a simultaneous equation model and parameter was estimated using the two stage least squares (2SLS) method that applies SAS/ETS (Statistical Analysis System/Econometric Time Series) program Versi 9.1 for Windows. Conclusions: Soybean production in Indonesia is strongly influenced by the price of soybeans at the farm level, prices of production facilities especially urea fertilizers and soybean seeds, labor wage and soybean imports in which these factors are influential through changes in the increase of crop acreage and soybean productivity. Soybean crop area width is very responsive to changes in prices or wages of agricultural labor both in short term and long term while soybean productivity is less responsive to its constituent factors. One of simulation policies was to increase soybean price in producer level at 35 percent, it would stimulate farmers to increase harvested area, soybean production and farmers welfare. Implications of Policies to increase soybean production, the government should formulate policies that will provide benefits to both producers and consumers. Policies that are partially formulated will not benefit both parties, but only one party. To encourage farmers to increase their production, government policies must not only provide a subsidy of production facilities but also give guarantees in price during harvest time because at this time the bargaining power of farmers is very low. Price protection policy is aiming at output price stability that will determine the farmers’ income, which in turn will change their welfare.
Keyword: Price fluctuated, producer welfare, soybean production

Judul: Dampak Kebijakan Harga Pembelian Pemerintah terhadap Kesejahteraan Produsen dan Consumen di Indonesia
Abstrak: Government Purchase Price Rice Policy is one of the important instruments in order to ensure national food security. The objectives of this research were to (1) analyze the factors that influence the supply and demand for rice in Indonesia, (2) to analyze the impact of the government purchase price rice policy on the producers’ and consumers’ welfare and, (3) to formulate alternative strategies that could ensure fair welfare distribution to both the producers and the consumers. Four policy alternatives set for the period 2002-2008 were simulated with econometric model of the Indonesian supply and demand of rice industry. Time Series secondary data 1980-2008, especially from BPS, Ministry of Agriculture and BULOG was rice quantitatively analyzed using a system of simultaneous equations econometric model. The econometric model is a simultaneous equations model consisting of eight behavioral equations and three identity equations. The Two Stages Least Squares (2SLS) method was used to estimate the parameters of the behavioral equations in the model. This study showed that the government price rice policy is good for increasing rice production but not the best policy for welfare and as a result the society as a whole is worse off. This study suggests that the government purchase price rice policy should be accompanied with other policies government programs like: (1) increased irrigated area and, (2) increased rice intensification through improved infrastructural development and, (3) high time food diversification is intensified to reduce overdependence on rice.
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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