Judul: Content Analysis of Consumer Reviews and Comments on E-commerce in Indonesia
Abstrak: Online consumer review (OCR) merupakan salah satu bentuk E-WOM yang dapat menjadi sumber informasi dan sumber acuan bagi calon konsumen dalam mengambil keputusan. Penelitian ini bertujuan untuk menganalisis isi review dan komentar konsumen pada e-commerce di Indonesia. Penelitian ini menggunakan desain penelitian mix method. Penelitian kuantitatif dilakukan dengan teknik survei menggunakan instrumen kuesioner. Penelitian kualitatif dilakukan dengan teknik analisis isi dan indepth interview. Analisis isi dilakukan dengan mengamati review dan rating yang diberikan konsumen pada produk fashion di toko online yang berada di e-commerce Shopee dan Tokopedia. Indepth interview dilakukan kepada dua konsumen dan satu penjual. Pengolahan dan analisis data dilakukan dengan menggunakan aplikasi Microsoft Excel, dan Statistical Package for Social Science (SPSS) 25.0. Data yang diperoleh dalam bentuk komentar dilakukan analisis sentimen. Hasil dari penelitian ini menunjukkan bahwa hampir semua konsumen melihat rating dan review sebelum membeli produk fashion. Kebanyakan konsumen hanya memberikan rating tanpa disertai dengan review. Hasil penelitian juga menunjukkan bahwa ulasan mengenai kualitas produk, dan ulasan mengenai harga merupakan ulasan paling banyak dibahas oleh konsumen yang membeli produk fashion. Terdapat konsumen yang memberikan komentar yang tidak sesuai, menggunakan kata-kata berulang atau kata-kata yang dipanjangkan hurufnya., Online consumer review (OCR) is a form of E-WOM that can be a source of information and a source of reference for potential consumers in making decisions. This study aims to analyze the content of consumer reviews and comments on e-commerce in Indonesia. This study uses a mixed method research design. Quantitative research is carried out by survey techniques using a questionnaire instrument. Qualitative research was conducted using content analysis techniques and in-depth interviews. Content analysis is carried out by observing reviews and ratings given by consumers on fashion products in online stores in the e-commerce Shopee and Tokopedia. In-depth interviews were conducted with two consumers and one seller. Data processing and analysis was performed using Microsoft Excel application, and Statistical Package for Social Science (SPSS) 25.0. The data obtained in the form of comments is subjected to a sentiment analysis. The results of this study indicate that almost all consumers look at ratings and reviews before buying fashion products. Most consumers only give ratings without being accompanied by a review. The results also show that reviews about product quality and reviews about prices are the most discussed reviews by consumers who buy fashion products. There are consumers who give inappropriate comments, use repetitive words or words that are lettered out.
Keyword: content analysis, e-commerce, online consumer rating, online consumer review, online shopping

Judul: Pengaruh Rating dan Online Customer Review Terhadap Keputusan Pembelian di E-commerce Shopee
Abstrak: Kemajuan teknologi informasi menimbulkan adanya E-commerce yang membuat aktivitas belanja menjadi semakin mudah. Berdasarkan jumlah pengunjung bulanan situs E-commerce pada kuartal IV 2020, Shopee merupakan E-commerce yang paling banyak dikunjungi oleh pengguna internet. Penelitian ini bertujuan menganalisis pengaruh rating dan online customer review terhadap keputusan pembelian di E-commerce Shopee. Sumber data menggunakan data primer yang diperoleh berdasarkan hasil pengisian kuesioner oleh responden dan data sekunder yang diperoleh melalui literasi jurnal ilmiah, buku, dan sumber bacaan lainnya. Penelitian ini dilaksanakan pada bulan juni 2022. Responden pada penelitian ini adalah mahasiswa Institut Pertanian Bogor. Teknik data yang digunakan yaitu uji validitas dan uji reliabilitas dengan metode pengolahan data yang digunakan yaitu analisis deskriptif dan SEM-PLS. Hasil penelitian menjelaskan bahwa Variabel rating berpengaruh secara positif dan signifikan terhadap variabel keputusan pembelian dan variabel customer online review berpengaruh secara positif dan signifikan terhadap keputusan pembelian., Advances in information technology have given rise to E-commerce which makes shopping activities easier. Based on the number of monthly visitors to E-commerce sites in the fourth quarter of 2020, Shopee is the most visited E-commerce by internet users. This study aims to analyze the effect of ratings and online customer reviews on purchasing decisions at E-commerce Shopee. Data sources use primary data obtained based on the results of filling out questionnaires by respondents and secondary data obtained through literacy in scientific journals, books and other reading sources. This research was conducted in June 2022. Respondents in this study were students of the Bogor Agricultural University. The data technique used is the validity test and reliability test with the data processing method used is descriptive analysis and SEM-PLS. The results of the study explain that the rating variable has a positive and significant effect on the purchasing decision variable and the online customer review variable has a positive and significant effect on the purchasing decision. Keywords: E-commerce, Online Customer Review, Rating, Purchase Decision, SEM-PLS
Keyword: E-commerce, Online Customer Review, Rating, Purchase Decision, SEM-Pls

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