Judul: Analisis Data Panel untuk Menentukan Peubah-peubah pada Laporan Keuangan yang Mempengaruhi Harga Saham (Studi pada Perusahaan Industri Barang Konsumsi yang Terdaftar di Bursa Efek Indonesia Periode 2008-2012)
Abstrak: Global population growth resulted in the increase of individual needs of consumer goods. This causes consumer goods companies to expand their business activities. Therefore, the companies need much capital. Capital can be originated from two sources i.e. capital from within the company such as the company’s net income, and capital from outside the company such as issuing stock. The data used in this research are panel data regarding the independent variables found in financial reports of the companies and stock price data of the consumer goods industries listed on Indonesia Stock Exchange during 2008-2012. Based on the results of this study, panel data regression model appropriate to describe the influence of the independent variables on the stock price is the individual fixed effect model. This model has R-Square value of 97.10%. Variables that has significant influence on the stock price are total assets, nett revenue, and business profit.
Keyword: stock price, panel data regression model, panel data analysis, Hausman test, Chow tes

Judul: Analysis Factor of The Effect of Changes in  Stock Prices Using Panel Data Regression
Abstrak: Saham merupakan salah satu instrumen pasar keuangan yang paling populer. Menerbitkan saham merupakan salah satu pilihan perusahaan ketika memutuskan untuk pendanaan perusahaan. Dalam karya ilmiah ini diteliti seberapa besar pengaruh rasio harga penghasilan dan rasio hutang terhadap harga saham yang beredar untuk emiten tertua di Bursa Efek Indonesia. Data yang digunakan merupakan data panel dari 7 perusahaan penerbit saham tertua di Bursa Efek Indonesia dengan rentang waktu harga saham yang diambil mulai dari 2016 hingga 2021. Peramalan harga saham ini akan dimodelkan menggunakan regresi data panel yang mempunyai 3 model yaitu model pengaruh gabungan, model pengaruh tetap individu, dan model pengaruh acak. Dari hasil penelitian didapatkan bahwa model pengaruh tetap individu dengan transformasi data adalah model yang terbaik untuk digunakan. Model tersebut menggambarkan pengaruh rasio harga penghasilan dan rasio hutang terhadap harga saham emiten tertua di Bursa Efek Indonesia memiliki nilai R square sebesar 97.56% dengan nilai MAPE dari model sebesar 1.94% dan nilai MAPE peramalan sebesar 5.20%., Stocks are one of the most popular financial market instruments. Issuing shares is one of the company's choices when deciding to fund the company. This scientific paper will examine how much price earnings ratio and debt ratio influence the stock prices outstanding for the oldest issuers on the Indonesia Stock Exchange. The data used is panel data from the seven oldest stock issuing companies on the Indonesia Stock Exchange with a time range of stock prices from 2016 to 2021. This stock price forecasting will be modeled using panel data regression, which has three models: the common effect model, the individual fixed effect model, and the random effect model. The study’s results found that the fixed effect model with data transformation is the best model to use. The model illustrates the influence of the price-earnings ratio and debt ratio on the stock price of the oldest issuer in IDX which has R square value of 97.56% with MAPE of model 1.94% and MAPE of forecasting 5.20%.
Keyword: stock, regression, panel data, price-earning ratio, debt ratio

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: