Duflo-Moore Operator for The Square-Integrable Representation of 2-Dimensional Affine Lie Group

In this paper, we study the quasi-regular and the irreducible unitary representation of affine Lie group  of dimension two. First, we prove a sharpening of Fuhr’s work of Fourier transform of quasi-regular representation of . The second, in such the representation of affine Lie group   is square-integrable then we compute its Duflo-Moore operator instead of using Fourier transform as in F hr’s work

Application of The Variance Minimization Model with a Certain Return for The Investment Portfolio of Seven Good-Performing Stocks on The IDX30 Index

Nowadays, investing in stocks is in great demand, especially among young people in Indonesia. In investing, investors will be faced with various problems in developing a good portfolio, including determining the assets for investment and determining the amount of capital required. Therefore, this study aims to determine how to choose stocks and the proportion of capital to invest in order to form an optimal portfolio. In this study, the Markowitz model is used to specifically minimize variance by constraining the number of weights and profit targets. An analysis of the closing prices of stocks included in the IDX30 index for the period August 2021 to January 2021 was carried out with data taken from September 11, 2020 to September 9, 2021, sourced from https://finance.yahoo.com/. The results of the study show that from 30 stocks, 7 stocks were selected that were categorized as good performers in each sector. Seven shares with the proportion of capital allocated for each share, namely BMRI (8.92051%), BRPT (3.718450%), ANTM (12.80686%), TBIG (23.30450%), MIKA (17.98822%), KLBF (7.96699%), and ASII (25.29447%)

Convergence Analysis from the Solution of Riccati’s Fractional Differential Equation by Using Polynomial Least Squares Method

Riccati's Fractional Differential Equation (RFDE) has become a topic of study for researchers because RFDE can model variety of phenomenon in science such as random processes, optimal control and diffusion problems. Phenomena that can be modeled in a mathematical form can make it easier for humans to analyze several things from that phenomenon. RFDE generally does not have an exact solution, therefore a numerical approach solution is needed, one of the methods that gives good accuracy to the actual or exact solution is Polynomial Least Squares, where the errors calculated based on mean absolute percentage error (MAPE) produce a percentage below 1%. In addition, the convergence of a sequence from approximate solutions indicates that the sequence will converge to a solution

Portfolio Analysis Using the Markowitz Model with Stock Lot Constraints and Target Returns or Without Target Returns

Stock investment activities are inseparable from returns and risk, so an investor needs expertise to minimize investment risk. One way is by forming an optimal portfolio. The purpose of this research is to determine the number of stock lots in the optimal portfolio. This research analyzes the closing prices of stocks during the research period with the criteria of stocks being listed on the IDX30 index consecutively for 20 periods and belonging to the large cap group (the stock market capitalization exceeds $10 billion). Then the number of stock lots is calculated using the Markowitz model with stock lot constraints and target returns or without target returns. From the selected stocks, an optimal portfolio is formed using Microsoft Excel. Based on the research results, a combination of an optimal portfolio with a target return is ASII: 5, BBCA: 10, BBNI: 23, BBRI: 1, BMRI: 23, TLKM: 93, UNVR: 12, where the risk is 0,000149 and the target expected return is 0,00155. Meanwhile, the optimal portfolio without a target return is ASII: 8, BBCA: 7, BBNI: 32, BBRI: 40, BMRI: 9, TLKM: 62, UNVR: 17, where a risk is 0,000147 and the expected return is 0,00148. This research can be used as a consideration for investors in determining investment portfolios

PENGUATAN KONSEP MATEMATIKA MELALUI ALAT PERAGA MATEMATIKA PERMAINAN DI SDN CIKUDA JATINANGOR

Dalam artikel ini, didiskusikan bagaimana memotivasi siswa-siswa sekolah dasar khususnya para siswa di SDN Cikuda Jatinangor dalam memahami konsep matematika melalui alat-alat pembelajaran matematika. Tujuan utamanya adalah untuk menarik minat siswa dalam memahami konsep dasar matematika dengan lebih mudah. Metode yang digunakan untuk mencapai tujuan ini adalah student learning center. Selain itu, diberikan juga penjelasan kepada salah seorang perwakilan guru dan siswa melalui praktik penggunaan alat-alat pembelajaran matematika tersebut. Lebih jauh, karena kondisi COVID-19, kegiatan ini juga direalisasikan melalui pembuatan video pembelajaran yang dapat diakses di YouTube. Fokus utama dalam kegiatan ini adalah penekanan pada penguatan konsep aritmetika. Di sisi lain, penguatan konsep siswa dilakukan melalui problem solving di aplikasi zenius

Robust Optimization Model for Internet Shopping Online Problems with Endorsement Costs in the Fashion Industry

Online business is a business activity carried out via the internet or digitally. Buying, selling, and advertising are done online through e-commerce, social media, or online shops. The products offered vary, including services, food, household needs, and fashion. Selling online is not limited by time and distance, and consumers can obtain information about products and services that can influence their decisions. At the same time, sellers also have the opportunity to advertise their products in a broader range by making endorsements. An endorsement is a form of advertising using well-known figures who are recognized, trusted, and respected by people. In this thesis, a model for optimizing the problem of online internet shopping with endorsement fees is formulated. This optimization model aims to maximize the profits gained by sellers in marketing their products online. In marketing products, there is uncertainty in the number of requests. To overcome this uncertainty, an approach is needed that can handle this uncertainty, namely Robust optimization. The Robust optimization model is solved using the polyhedral uncertainty set approach, resulting in a computationally tractable optimal solution.   Keywords: internet shopping online; endorsement costs; robust optimization

Analisis Hubungan Inflasi, Indeks Harga Konsumen dan Jumlah Uang Beredar di Indonesia Menggunakan Model Vector Autoregressive Integrated (VARI)

Data ekonomi merupakan data deret waktu yang cenderung fluktuatif dan mengandung trend, sehingga menyebabkan data tidak stasioner dan perlu dilakukan proses differencing. Metode Vector Autoregressive Integrated (VARI) adalah salah satu metode yang dapat digunakan pada data deret waktu multivariat yang mengalami proses differencing. Dalam penelitian ini, dilakukan pemodelan data inflasi, indeks harga konsumen dan jumlah uang beredar di Indonesia dengan model VARI, penaksiran parameter dengan Maximum Likelihood Estimation (MLE), analisis hubungan antar variabel dengan uji kausalitas Granger, dan uji keakuratan hasil peramalan dengan Mean Absolute Percentage Error (MAPE). Pada hasil penelitian diperoleh model VARI (1,1). Hasil uji kausalitas Granger pada model VARI (1,1) menunjukkan inflasi, indeks harga konsumen, dan jumlah uang beredar memiliki hubungan kausalitas dua arah. Nilai MAPE antara 20% - 50% untuk variabel inflasi dan indeks harga konsumen dan < 10% untuk variabel jumlah uang beredar, sehingga kedua model cukup baik digunakan untuk peramalan inflasi dan indeks harga konsumen, dan sangat baik digunakan untuk peramalan jumlah uang beredar.   Kata Kunci: deret waktu, VARI, MLE, uji kausalitas Granger, peramalan, MAPE

STRUKTUR AFFINE ALJABAR LIE REAL DARI GRUP LIE SIMILITUDE BERDIMENSI 4

Dalam artikel ini, dibahas tentang sifat-sifat aljabar Lie real dari grup Lie similitude berdimensi 4 termasuk struktur affine yang termuat di dalamnya. Tujuannya adalah untuk membuktikan bahwa aljabar Lie real dari grup Lie similitude berdimensi 4 mempunyai struktur affine. Untuk mendapatkan hasil tersebut, rumus affine dihitung terhadap basisnya yang diinduksi dari struktur simplektiknya. Lebih jauh, metode penelitian yang digunakan adalah studi literatur terhadap beberapa artikel yang relevan. Sebagai hasil utamanya, diperoleh rumus eksplisit struktur affine pada aljabar Lie dari grup Lie similitude berdimensi 4

Optimisasi Portofolio Expected Shortfall Pada Saham Sektor Energi dan Pertambangan

Saham sebagai salah satu produk investasi di pasar modal Indonesia tentunya memiliki risiko yang dapat memengaruhi keputusan investor dalam berinvestasi, dalam menentukan risiko dapat dilakukan dengan melihat diversifikasi portofolio dari beberapa saham. Data saham meliputi perusahaan energi dan pertambangan yang memenuhi kriteria kapitalisasi pasar besar dan Debt to Equity Ratio (DER) rendah. Salah satu metode yang dapat digunakan untuk membentuk diversifikasi portofolio adalah Expected Shortfall (ES). ES adalah nilai ekspektasi dari return jika return tersebut melampaui batas return maksimum (Value-at-Risk). Dengan tujuan untuk meminimumkan risiko investasi. Dari perhitungan ES didapat masing-masing proporsi saham dalam satu portofolio optimal, dari beberapa portofolio yang dibentuk terlihat bahwa portofolio yang terdiri dari kombinasi saham paling banyak maka portofolio tersebut menghasilkan risiko yang paling rendah. Data dalam penelitian ini adalah data harga penutupan saham harian sector energi dan pertambangan periode Januari 2016 – Januari 2019. Ada beberapa tahap dalam penelitian ini. Langkah pertama adalah menghitung nilai return setiap saham perusahaan. Kemudian menghitung nilai expected return dan korelasi antar saham dari setiap saham perusahaan. Setelah itu pembentukan portofolio dan perumusan portofolio dengan menggunakan Expected Shortfall dengan fungsi tujuan yang dibentuk

Analysis of the Company's Cash Flow Statement Kopinian Café

Café is a very popular place for young people today, so many entrepreneurs open up opportunities in this business, but seeing a promising market, entrepreneurs still find it difficult to manage their financial reports. Financial reports are important for a company to know the financial condition of the business being run, and the preparation of non-detailed financial statements will also have a big impact on the company, which causes difficulties in developing a business and including investment capital. With the existence of financial reports on. This writing aims to help the company "Kopinian" Café improve company performance by identifying the company's current financial condition. The cash flow statement method is sourced from the income statement and balance sheet report. This statement of cash flows is prepared with three business activities: cash flows from operating activities, investing activities, and financing activities. Kopinian Café has good management performance, shown by companies that can ideally pay current debts, pay liabilities, and manage inventory turnover