Judul: Studi terhadap Perencanaan Premi Optimal dengan Reinstatements pada Perusahaan Reasuransi.
Abstrak: Reinsurance is an underwrite all or a portion of the insurance risk. Insurer paid a number of premiums to reinsurer and that premiums would be income for reinsurer. Premium plan is very important for reinsurer facing risks of submitted claims. Premium plan in this paper is premium plan of reinsurance with reinstatement. This premium is not paid in the beginning of the contract, but it is paid when the loss of the reinsurer exceed maximum bound capacity of reinsurer. For illustration purpose, it is assumed that the reinsurer’s loss is satisfied a truncated exponential distribution. Reinsurance contract minimizes the expectation of square the difference between the total premium income and the loss of the reinsurance, therefore it is said to be optimal. Minimizing the expectation of square all over premium plans can be viewed as a credibility problems. Covariance matrix of the explanatory random variables of premium plan with reinstatement is invertible, so that the premium plan has a unique solution. Optimal premium plan are unbiased and nonnegative.
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Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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Judul: Keberagaman Bambu Marga Schizostachyum Nees di Jawa
Abstrak: Marga Schizostachyum merupakan bambu berdiameter buluh kecil, berdinding tipis, beruas panjang dengan percabangan pada satu buku yang sama besar. Catatan pertama marga Schizostachyum di Jawa sejak tahun 1829 bersamaan dengan terbitnya Schizostachyum blumei Nees. Hingga 2001, tercatat ada 10 jenis bambu Schizostachyum di Jawa yaitu: S. brachycladum (Kruz) Kruz, S. iraten Steudel, S. aequiramosum Widjaja, S. silicatum Widjaja, S. zolingeri Steudel dan Schizostachyum sp. Namun masih terdapat beberapa jenis Schizostachyum yang perlu diidentifikasi dan dicari sebarannya secara alami. Penelitian dilakukan dari September 2017 hingga 2019 dengan metode eksplorasi. Sampel bambu dikoleksi dari Malingping, Lebak, Bogor, Sumedang, Kuningan, Pekalongan, Batang, Purwokerto, Malang, Jember, Probolinggo dan Banyuwangi sebanyak 49 spesimen. Pengamatan morfologi menggunakan 24 karakter vegetatif dan 12 karakter generatif. Analisis data dilakukan dengan SIMQUAL (Similarity for Qualitative Data), SM (Simple Matching) dan SAHN (Sequential, Aglomerative, Hierarchical and Nested), menggunakan metode UPGMA (Unweighted Pair Group Method with Arithmethic Mean) pada software NTSys pc. 2.02i. Dalam penelitian ini, sekitar 13 jenis bambu marga Schizostachyum ditemukan di Pulau Jawa, 6 diantarnya jenis baru, 1 catatan baru dan 1 jenis penemuan kembali. Jenis-jenis bambu Schizostachyum di Pulau Jawa yaitu: Schizostachyum abrorii, S. aequiramosum, S. brachycladum, S. biflorum, S. castaneum, S. iraten, S. jatigedensis, S. hartanai, S. batangensis, S. silicatum, S. sengkol dan S. widjajai. Hasil analisis morfologi menunjukkan bahwa bambu Schizostachyum di Jawa mengelompok menjadi 4 kelompok berdasarkan posisi dan lebar daun pelepah buluh serta bentuk aurikel pelepah buluh. Kelompok pertama terdiri dari Schizostachyum abrorii, S. brachycladum dan S. zollingeri. Kelompok kedua terdiri dari Schizostachyum aequiramosum, S. castaneum dan S. jatigedensis. Kelompok ketiga terdiri dari Schizostachyum batangensis, S. widjajai, S. iraten dan S. sengkol. Kelompok keempat terdiri dari Schisostachyum hartanai, S. biflorum dan S. silicatum.
Keyword: bambu, Jawa, Schizostachyum