Judul: Analysis of Stock Exchange, Mining Commodity, Exchange Rates, and Energy Sector Stock Index using Vector Error Correction Model
Abstrak: Sektor Energi merupakan salah satu sektor yang memiliki pengaruh signifikan terhadap pertumbuhan ekonomi suatu negara secara umum. Kenaikan pertumbuhan ekonomi selalu berkaitan dengan penggunaan energi, di mana perkembangan ekonomi yang terus meningkat akan mengakibatkan peningkatan permintaan akan energi. Oleh karena itu, penelitian ini bertujuan untuk menganalisis faktor yang berpengaruh terhadap indeks saham sektor energi di Indonesia menggunakan Vector Error Correction Model (VECM). Data yang digunakan adalah indeks saham sektor energi, harga minyak bumi, harga batu bara, harga gas, indeks Nikkei, indeks Shanghai, indeks Dow Jones, dan kurs periode Januari 2021 hingga Maret 2023. Hasil analisis VECM menunjukkan bahwa pada jangka pendek harga minyak bumi dan harga batu bara berpengaruh nyata terhadap indeks saham sektor energi. Pada jangka panjang peubah yang berpengaruh nyata adalah harga batu bara, harga gas, indeks Nikkei, dan kurs. Hasil analisis Impulse Response Function (IRF) menunjukkan adanya shock pada indeks saham sektor energi, harga minyak bumi, dan harga batu bara dapat meningkatkan indeks saham sektor energi. Sebaliknya, adanya shock indeks Nikkei dapat menurunkan indeks saham sektor energi. Hasil Forecast Error Variance Decomposition (FEVD) menunjukkan bahwa kontribusi peubah indeks saham sektor energi, harga minyak bumi, harga batu bara, dan harga gas sudah nyata dalam menjelaskan perilaku perubahan indeks saham sektor energi., Energy Sector is one of the sectors that has a significant impact on the overall economic growth of a country. Economic growth is always linked to energy consumption, as increasing economic development leads to higher energy demand. Therefore, this study aims to analyze the factors influencing the energy sector stock index in Indonesia using Vector Error Correction Model (VECM). The data used include the energy sector stock index, crude oil prices, coal prices, gas prices, Nikkei Index, Shanghai Index, Dow Jones Index, and exchange rates from January 2021 to March 2023. VECM analysis results indicate that in the short term, crude oil prices and coal prices have a significant impact on the energy sector stock index. In the long term, significant factors are coal prices, gas prices, Nikkei Index, and exchange rates. The Impulse Response Function (IRF) analysis reveals that shocks to the energy sector stock index, crude oil prices, and coal prices can increase the energy sector stock index. Conversely, shocks to the Nikkei Index can decrease the energy sector stock index. The Forecast Error Variance Decomposition (FEVD) results demonstrate that the contributions of the energy sector stock index, crude oil prices, coal prices, and gas prices are significant in explaining the behavior of changes in the energy sector stock index.
Keyword: FEVD, IDX Energy, IRF, VECM

Judul: Analisis Faktor yang Memengaruhi Pergerakan Harga Indonesia Stock Exchange Industrial Classification
Abstrak: Indonesia Stock Exchange Industrial Classification (IDX-IC) an investment benchmark for investors to see sectoral stock movements are expected to move stable to increase the amount of investment that can help increase the Company’s Capital Stock to maximize the quantity and quality of production and ultimately encourage Indonesia’s economic growth. However, uncertain economic conditions are often a factor in unstable stock price movements, such as fluctuations in the exchange rate, which illustrates the strenght of a country’s economy, world gold price as an alternative investment when the stock market is volatile, world crude oil an its derivative products which are still inouts and driving operations companies. The Covid-19 case caused concern in the community, so it attracted investment in the stock market. This study aims to analyze (1) the factors that influence the IDX-IC price movement, (2) the impact of factor shocks that affect the movements of the IDX-IC sectoral stock price indeks in the coming period, (3) the contribution of factors in influencing the movement of the IDX-IC sectoral stock price index in coming period, and (4) structural breaks in the IDX-IC sectoral stock price index. The method to analyze the influence of factors that influence IDX-IC price movements is Vector Autoregression (VAR)/ Vector Error Correction Model (VECM). The method to determine the impact of shocks in the future uses the Impulse Response Function (IRF) test. The variable contribution is analyzed by the Forecast Error Variance Decomposition (FEVD) test. The method to identify the presence of structural breaks in the data uses the CUSUM tes tand the F-test. The results of the analysis show that the exchange rate has a positive effect on the movement of the stock price index in the industrial sector and the transportation and logistics sector. The world gold price has a negative effect on the movement of stock price indexes in the energy, industrial, health and financial sectors. Positive confirmed cases of Covid-19 have a negative effect on stock price movements in the transportation and logistics sectors. The factor variable shocks were responded to differently by each sector. However, the shock response was the same in the 2nd period, then returned to the equilibrium point in the 5th period and was stable until the 10th period. IDX-IC's contribution is more dominant than other factors in influencing its movement in the subsequent 10 periods, followed by the contribution of world gold prices, exchange rates, Covid-19 cases and world crude oil prices. The structural break occurred from June 4, 2021, to October 1, 2021, due to restrictions on public mobility and the high stock price deemed unreasonable. Based on the results of the study, there are several recommendations. First, paying attention to the optimization of monetary policy has implications for the stability of the price index in the industrial sector and the transportation and logistics sector by maintaining the stability of interest rates and inflation closely related to the exchange rate. Second, the decision of investors to make safe havens can be one of the focuses of the government to control the stock market when there is turmoil. Government
Keyword: IDX-IC, World Gold Prices, World Crude Oil Prices, Covid-19 Cases, Exchange Rates

Judul: Karakteristik Anatomi Skelet Kepala Buaya senyulong (Tomistoma schlegelii).
Abstrak: Buaya sepit atau senyulong (Tomistoma schlegelii) merupakan jenis buaya asli Indonesia yang berhabitat di sungai-sungai Sumatera, Kalimantan, dan juga pedalaman Sulawesi. Salah satu ciri khas buaya senyulong adalah bentuk moncong yang runcing dan sempit, namun hingga saat ini informasi mengenai struktur skelet kepala buaya senyulong sangat terbatas. Penelitian ini bertujuan untuk mempelajari karakteristik anatomi skelet kepala buaya senyulong yang dikatikan dengan fungsi dan perilakunya. Penelitian dilakukan secara eksploratif dengan melakukan pengamatan, pencatatan, dan pengambilan gambar dari skelet kepala buaya senyulong. Skelet kepala berukuran panjang 70 cm, lebar 29 cm, dan tingggi 17 cm dengan permukaan kasar pada os nasale, os frontale, os maxilla, os mandibula, os lacrimale, os jugale. Jumlah gigi pada buaya ini sebanyak 78 buah, terdiri dari 4 buah gigi premaxila, 16 buah gigi maxila, dan 19 buah gigi mandibula. Pada regio orbitalis ditemukan dua pasang fenestrae temporales yang berkembang baik. Fenestra supratemporale merupakan lubang oval yang membentang di sepanjang os parietale. Fenestra infratemporale berbentuk segitiga dan dibatasi oleh os squamosum, os postorbitale, os jugulare, dan os quadratum. Os mandibula hewan ini mempunyai symphysis mandibularis yang panjang yaitu garis yang melintang di corpus mandibulae. Secara fungsional ukuran symphysis mandibularis berkaitan dengan adaptasi hewan terhadap diet makan.
Keyword: kepala, moncong, Tomistoma schlegelii