Judul: Pembangunan Sistem Bonus Malus Praktis dari Sistem Bonus Malus Optimal dengan Menggunakan Sebaran Hofmann
Abstrak: Pembangunan Sistem Bonus Malus Praktis dari Sistem Bonus Malus Optimal dengan Menggunakan Sebaran Hofmann
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Judul: Sistem Bonus Malus dengan Frekuensi Klaim Berdistribusi Geometrik dan Ukuran Klaim Berdistribusi Weibull
Abstrak: Bonus-Malus system is one of systems implemented by an insurance in calculating the risk premium based on claim history from each policyholder. In this work we discussed two different types of Bonus-Malus system namely the classical Bonus-Malus system and the optimal Bonus-Malus systems. The classical Bonus-Malus system sets the risk premium by taking into account only the number of accidents of each policyholder. While the optimal Bonus-Malus system sets the risk premium by taking into account both the frequency and the severity of the claims of each policyholder. Both of the Bonus-Malus systems are then compared, with the number and size of the claims and insured persons are assumed to follow respectively a geometric and a Weibull distributions. The risks faced by each policyholder are different such that the number and size of the claims experienced by each policyholder are also different. Fu r t h e rmo r e , posterior distribution o f severity and frequency claim parameters is estimated by using Bayes method. Subsequently, solutions of both systems are obtained in term of future premium based on claim history from each policyholder.
Keyword: Bogor Agricultural University, Weibull distribution., geometric distribution, Bonus-Malus systems

Judul: Phylogeography and Species Limits in the Papuan White Snake (Micropechis ikaheka) (Reptilia: Serpentes: Elapidae)
Abstrak: Papua white snake, Micropechis ikaheka, has been distingushed into two subspecies M.i. ikaheka and M.i. fasciatus. However, due to lack of data on their morphology, distribution and ecology, both subspecies often ignored in scintific discussions and refers only byas , Micropechis ikaheka. This study was designed to document the differences between M.i. ikaheka and M.i fasciatus by using scales characteristics and reproductive organ or hemipenes. The study also examine, zoogeography, habitat, diet and cannibalism of both subspecies to better understanding the the ecology of one of the most venomous snakes in the world. This study consists of three topics with method and also different in the size samples, respectively. The first study is the histology and microtopography of the skin were studied using paraffin method and Scanning Electron Microscope (SEM). The second is the hemipenis were examined by following Myers and Cadle (2003), and Zaher and Prudente (2003). The third is the abdominal surgery was carried out to document diet type and the investigate phenomenon of cannibalism in the snake. Specimens for this study came from the collection from Museum Zoologicum Bogoriense (MZB) and Universitas Negeri Papua’s Laboratory (LZU). The research result also indicated that the markers of skin and hemipenis described the same structure and microornamentation in all M. ikaheka groups being compared. Based specimens examined morphological descriptions do not s support the further differentiation in Micropechis. In short, two markers that used in this study could not sufficiently indicate the differences in the level of species and subspecies of M. ikaheka. The study, however, were able to delineate zoogeography and skin color patterns, which fall into four groups: M. i. ikaheka; M. i. fasciatus. M. i. ssp. “intermediate”; and M. i. ssp “black”. This study also revealed that color variations did not overlap in their geographic distribution. It is therefore, it suggested that environmental factors may contribute to the skin color variations. It also assumed that habitat discontinuous and biogeography factors may also cause the loss of the connection between the original populations (vicarians) or follow colonization events (dispersal). The examined of 22 stomach contents of M. ikaheka shows this species is carnivorous, and prey on vertebrates such as amphibians, fish, reptiles, and Mammals. These snakes are opportunistic predators since they prey on all that can be captured, but mainly reptiles (61.5%), followed by mammals and fish (both 15.4%), and amphibians (7.7%). Although categorized as terrestrial animal, the diet study showed that M. ikaheka snakes often go into the water to hunt for fish (the sample from Yapen island), including eel (the sample from Aru island). Based on prey items indentified, there is evidence that M. ikaheka is cannibal. At this time, there still no record on reason for cannibalism, but it is assumed that cannibalism was due to competition between populations and means to control population.
Keyword: geographic variation, white snake, papua