Judul: Perbandingan Kekonvergenan Beberapa Model Binomial untuk Penentuan Harga Opsi Eropa
Abstrak: Kontrak opsi (selanjutnya disebut opsi) adalah suatu jenis kontrak antara dua pihak, satu pihak memberi hak kepada pihak lain untuk menjual atau membeli aset tertentu pada harga dan periode waktu tertentu. Terdapat dua jenis opsi yang paling mendasar, yaitu opsi call dan opsi put. Berdasarkan waktu eksekusi maka terdapat dua tipe opsi, yaitu opsi Eropa dan opsi Amerika. Untuk menentukan besarnya premi opsi maka dirumuskan dua cara yaitu dengan solusi analitik dan solusi numerik. Solusi analitik telah ditemukan oleh Black-Scholes pada tahun 1973. Metode numerik yang sering digunakan adalah metode beda hingga dan metode binomial dan trinomial. Beberapa model binomial hanya mendasarkan pada perbedaan faktor naik dan turun dari perkembangan harga saham. Metode binomial terutama digunakan untuk penentuan nilai opsi yang tidak dapat diturunkan secara analitik. Di antara modelmodel binomial tersebut adalah model CRR, JR, Tian, PP1, dan PP2. Model ini konvergen ke solusi Black-Scholes. Untuk melihat kevalidan masing-masing model perlu diketahui sifat-sifat kekonvergenannya, maka perlu melihat pendekatan numeriknya.
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Judul: European Option Pricing Using the Monte Carlo Method and the Finite Difference Method
Abstrak: Harga opsi Eropa umumnya dihitung menggunakan model Black-Scholes. Model ini dapat digunakan ketika asumsinya terpenuhi. Perdagangan opsi pada kenyataannya tidak memenuhi beberapa asumsi, sehingga model Black-Scholes tidak dapat memberikan solusi analitik untuk harga opsi. Hal ini menjadi alasan dibutuhkannya metode numerik untuk menghitung harga opsi Eropa. Pada penelitian ini digunakan dua metode numerik, yaitu metode Monte Carlo yang menghitung harga opsi dengan melakukan simulasi harga saham dan metode beda hingga yang melakukan diskretisasi pada persamaan diferensial parsial. Karya ilmiah ini memeriksa kekonvergenan untuk tiap metode. Selanjutnya, diperiksa pengaruh dari beberapa parameter terhadap harga opsi menggunakan metode beda hingga. Waktu jatuh tempo opsi dengan harga opsi memiliki hubungan yang berbeda untuk kondisi tertentu dan volatilitas harga saham berbanding lurus dengan harga opsi., European option prices are generally calculated using the Black-Scholes model. This model can be used when the assumptions are fulfilled. In fact, options trading does not fulfill several assumptions so the Black-Scholes model cannot provide an analytical solution for option prices. This is the reason for the need of numerical methods to calculate European option prices. This study uses numerical methods such as the Monte Carlo method which calculates option prices by simulating stock prices and the finite difference method which performs discretization on partial differential equations. This paper examines the convergence for each method. Next, we examine the effect of several parameters on the option price using the finite difference method. The expiration time of the option and the option price has a different relationship for certain conditions and the volatility of the stock price is directly proportional to the option price.
Keyword: European option, finite difference method, Monte Carlo method, option

Judul: Sebaran Spasial dan Karakteristik Habitat Buaya Air Tawar Irian (Crocodylus novaeguineae Schmidt,1928) di Taman Nasional Wasur
Abstrak: Rawa BIRU lake is the biggest lake in Wasur National Park (WNP) and it is a habitat for Irian freshwater Crocodile (Crocodylus novaeguineae). Now adays, their population become decreasing and it caused by hunting, a less data about their habitat and not enough knowledge about their dispersion in every parts of the lake. If this condition still happened, the existence of Irian freshwater Crocodile will threatened and more over they will be extinct so for prevent this situation we need management action. therefore it needs a study about habitat characteristic of Irian freshwater Crocodile and their dispersion in every parts of the lake as a referention and consideration for the next management action. The research was conducted in Rawa Biru lake, SPTN III Wasur, WNP, Merauke, Province of Papua, during April-May 2008 (Rainy season). This research is based on exploration method and taking samples for habitat, which is consist of cover, water and foods potential. Data of spatial dispersion using transect method and GPS (Global Positioning System) through around the edge of the lake. Besides, data of traditional knowledge, habitat disturbance and management using observation and interview methods. Irian freshwater Crocodile use vegetations like tebu rawa (Hanguana malayana) and rumput pisau (Pandanus sp) around the lake as a place to nesting, basking, covering and searching the foods. The nest have a shape like a mound, it was made from leaf manures of tebu rawa and rumput pisau, leaves and branches of pulai (Alstonia scholaris) and branches of Sagu (Metroxylon sagu) with length about 1,8-2,1 meters, width 2,1 meters and height about 60-75 centimeters, it lies under the stand. There also find a little mudhole and resting place of female crocodile closed by the nest. The breadth of basking place was influenced by body size, number of individual and utilizing intensity. In upper part zone of Rawa Biru lake (North side of the lake/kali mati) was found 4 crocodile, nesting and active basking places. Upper part zone is far from the village and it still far from human disturbance. One of the most common food of crocodile is sembilang fish. Middle part zone of the lake get a disturbance from human in the form of calladium plantation (Thyponium sp) upon roots of tebu rawa and rumput pisau, heavy traffic of boat also disturbance from human. It was found 1 mujahir fish and 3 long-neck turtle as crocodile's foods. In the lower course zone (South side of the lake/people called it was head of the lake) does not find any foot print or track of crocodile, it caused by lower course have the near distance from the village and it already get disturbance from human like back and forth of the boat and often using as a place to searching fish and along tome ago it was used as place to crocodile hunting. Irian freshwater Crocodile using Rawa Biru lake and vegetation under it as a places to nesting, basking, covering and searching their foods. Dispersion of their nesting and basking places in every zone of Rawa Biru lake was influenced by human disturbance
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