Judul: The Effect of Corporate Social Responsibility on Financial Performance (A Comparison between Indonesia and Australia)
Abstrak: Setiap perusahaan memiliki tanggung jawab untuk melakukan kegiatan tanggung jawab sosial dan lingkungan (TJSL), pelaporan terhadap keberlanjutannya, serta mengelola dan mengembalikan dana yang diberikan oleh shareholders. Tujuan penelitian ini adalah menganalisis hubungan TJSL dengan kinerja keuangan di perusahaan Indonesia dan Australia, membandingkan pengungkapan TJSL di Indonesia dan Australia, dan membandingkan pengungkapan TJSL disetiap sektor. Sampel yang digunakan adalah perusahaan yang terdaftar pada LQ45 untuk Indonesia dan ASX50 untuk Australia. Metode yang digunakan adalah regresi linear sederhana. Hasil yang diperoleh ialah TJSL berpengaruh positif dan signifikan terhadap ROA di kedua negara namun tidak berpengaruh signifikan terhadap ROE. Selanjutnya, Australia memiliki pengungkapan TJSL yang lebih unggul dibandingkan Indonesia serta terdapat perbedaan pengungkapan secara kuantitas pada sektor-sektor yang menjadi sampel penelitian. Hal ini menunjukkan perlu adanya peningkatan pelaporan TJSL yang didukung oleh perencaan TJSL secara matang oleh perusahaan di Indonesia., Every company has a responsibility to carry out corporate social responsibility (CSR) activities, reporting on its sustainability, as well as managing and returning funds provided by shareholders. The purpose of this study was to analyze the relationship between CSR and financial performance in Indonesian and Australian companies, compare CSR disclosures in Indonesia and Australia, and compare CSR disclosures in each sector. The samples used are companies listed on LQ45 for Indonesia and ASX50 for Australia. The method used is simple linear regression. The results showed that CSR has a positive and significant effect on ROA in both countries but has no significant effect on ROE. Furthermore, Australia has superior CSR disclosures than Indonesia and there are differences in disclosure in quantity in the sectors that are the research sample. This shows that Indonesian companies need to increase their CSR reporting, which is supported by careful planning.
Keyword: Australia, Indonesia, ROA, ROE, corporate social responsibility

Judul: The Effect of Corporate Social Responsibility Disclosure on Financial Performance and  Firm Value (Comparative Study between Manufacturing Companies Listed in Indonesia  Stock Exchange and Malaysia Stock Exchange in 2016-2020)
Abstrak: Seiring dengan persaingan bisnis yang semakin ketat, perusahaan dituntut tidak hanya fokus untuk kepentingan internal tetapi harus bisa memberikan dampak kepada masyarakat dan lingkungan sekitar. Sehingga hal ini membuat perusahaan harus melalukan kegiatan CSR. Kegiatan CSR dijalankan perusahaan bersamaan dengan pengungkapan CSR. Pengungkapan CSR penting untuk dilakukan perusahaan akan memiliki pengaruh terhadap kinerja keuangan dan nilai perusahaan. Penelitian ini dilakukan dengan tujuan untuk mengetahui pengaruh pengungkapan CSR terhadap kinerja keuangan dan nilai perusahaan dengan melakukan studi komparasi pada perusahaan manufaktur yang terdaftar di BEI dan Bursa Malaysia. Penelitian ini menggunakan data sekunder yang bersumber dari laporan tahunan serta laporan berkelanjutan perusahaan. Perhitungan pengungkapan CSR diukur berdasarkan standar Global Reporting Initiative (GRI) G4. Metode pengolahan data menggunakan analisis rasio keuangan, analisis nilai perusahaan, serta uji beda Mann-Whitney yang digunakan untuk mengetahui tingkat perbedaan pengungkapan CSR di Indonesia dan Malaysia. Hasil penelitian menunjukkan bahwa pengungkapan CSR pada perusahaan manufaktur di Indonesia berpengaruh signifikan terhadap kinerja keuangan dan nilai perusahaan. Sementara pada perusahaan Malaysia, tidak ada pengaruh signifikan pengungkapan CSR terhadap kinerja keuangan dan nilai perusahaan. Pada penelitian ini juga didapatkan bahwa pengungkapan CSR di kedua negara tersebut tidak memiliki perbedaan yang signifikan., Along with increasingly fierce business competition, companies are required not only to focus on internal interests but must be able to have an impact on the community and the surrounding environment. So this makes the company must carry out CSR activities. CSR activities are carried out by the company in conjunction with CSR disclosure. CSR disclosure is important for companies to have an influence on financial performance and company value. This study was conducted with the aim of knowing the effect of CSR disclosure on financial performance and firm value by conducting a comparative study on manufacturing companies listed on the Indonesia Stock Exchange and the Malaysia Stock Exchange. This study uses secondary data sourced from annual reports and company sustainability reports. Calculation of CSR disclosure is measured based on the Global Reporting Initiative (GRI) G4 standard. The data processing method uses financial ratio analysis, firm value analysis, and the Mann-Whitney difference test which is used to determine the level of differences in CSR disclosure in Indonesia and Malaysia. The results show that CSR disclosure in manufacturing companies in Indonesia has a significant effect on financial performance and firm value. Meanwhile, in Malaysian companies, there is no significant effect of CSR disclosure on financial performance and firm value. In this study, it was also found that CSR disclosure in the two countries did not have a significant difference.
Keyword: corporate social responsibility disclosure, financial performance, firm value, indonesia, malaysia

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model