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: Asuransi Optimal dan Kebijakan Reasuransi dalam Proses Risiko
Abstrak: Insurer has a risk to bankrupt because the distribution of its claim size has a thick tail. This means that the probability of a big claim is relatively high. For this situation, insurer divides a part or all risk of to other insurer (reinsurance) to minimize the expected maximal losses. Insurer can optimize insurance policies, reinsurance, or both. When insurer optimizes insurance policies for minimizing the expected maximal losses, insurer limits its claim size to be paid by insured. When insurer optimizes reinsurance, insurer do not limit the claim size submitted by insured but insurer just paid a part from the claim submitted by insured and the rest being paid reinsurance. When insurer uses the combination polices, insurer limits the claim size submitted by insured and insurer paid a part from the claim it and the rest being paid by reinsurance. The result of optimizes insurance policies, reinsurance, or both is a stop loss policy to minimize the expected maximal losses.
Keyword: reinsurance., insurance policies, insurance, risk

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