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This study aims to develop a predictive model using linear regression to identify potential arrhythmias in the elderly based on electrocardiogram (ECG) data. Data were collected through observations at healthcare facilities from elderly patients with indications of arrhythmia, then preprocessed such as cleaning, normalization, feature selection, and outlier checking were carried out. The features used include PR interval, QRS duration, QT interval, and heart rate. The dataset was divided into training data (80%) and test data (20%) to build and evaluate the model. The training results showed that the model was able to predict the risk of arrhythmia with a Mean Squared Error (MSE) value of 0.15 and a coefficient of determination (R²) close to 1. Evaluation using a confusion matrix showed an accuracy of 76.19%, precision of 82.80%, recall of 76.19%, and F1 score of 72.70%. These results prove that linear regression can be used as an initial approach in the early detection of arrhythmias non-invasively in the elderly. This study provides a foundation for the development of ECG data-based clinical decision support systems and suggests future exploration of more complex models and integration with real-time monitoring technologies.

Credit card fraud is a critical issue in digital financial transactions. This study aims to develop and evaluate fraud detection models using Logistic Regression and Gradient Boosting on an imbalanced dataset, where fraudulent transactions constitute only a small portion of the data. To address this imbalance, the Synthetic Minority Over-sampling Technique (SMOTE) was applied during preprocessing. Logistic Regression, used as a baseline model, achieved 95% accuracy, 78.6% precision, 55.9% recall, and a 65.3% F1-score. After applying class weighting and SMOTE, recall improved to 88.7%, but precision dropped to 52%, indicating that the model became overly sensitive and prone to false positives. Gradient Boosting initially produced better results, with 98% accuracy, 95.5% precision, 84.3% recall, and an 89.5% F1-score. After hyperparameter tuning and resampling, its performance improved further to 96.7% precision, 86.1% recall, and a 91.1% F1-score. These results indicate that Gradient Boosting is more effective in handling imbalanced data and offers greater reliability in detecting fraudulent transactions. The findings support the growing evidence in favor of ensemble learning techniques in fraud detection applications. This research contributes practical insights into improving the accuracy and security of machine learning-based fraud detection systems in financial services.

Social media has become a strategic tool for the government to disseminate public information quickly, interactively, and efficiently in the digital era. The Lampung Provincial Government utilizes various social media platforms such as Facebook, Instagram, and TikTok to support public communication activities. This study aims to analyze the effectiveness of public communication by measuring the level of activity of Regional Apparatus Organization (OPD) social media accounts using the logistic regression method. Data were collected through web scraping techniques on the official OPD social media accounts and then processed using a quantitative approach. The results show that the level of social media activity influences the effectiveness of public communication and the transparency of government information. These findings are expected to serve as a basis for local governments in designing public communication strategies that are more optimal and adaptive to developments in digital technology.

Credit scoring is an important element in decision-making for providing financing, especially for microfinance institutions. Several methods for predicting credit scoring include Decession Tree, Gradient Boosted, Neural Network, K-NN, and Rule Induction. This study aims to improve the accuracy of financing risk prediction by efficiently integrating historical data. The Neural Network (NN) algorithm is a machine learning algorithm consisting of neurons (nodes) connected to each other in several layers (input, hidden, and output). NN is used for pattern recognition, classification, regression, and complex non-linear modeling. The NN algorithm has the advantage of working well on large and diverse data and unstructured data. However, the NN algorithm has weaknesses such as overfitting and data dependence. In this study, the integration of the Sample Bootstrapping and Weighted Principal Component Analysis (PCA) methods is proposed to improve optimal accuracy in the NN algorithm. The Sample Bootstrapping method is used to reduce the amount of training data to be processed. The Weighted PCA method is used to reduce attributes. This study uses a financing customer dataset. The results of the study show that the integration of the NN algorithm with Sample Bootstrapping and Weighted PCA resulted in an accuracy increase of 1-3% (97%-99%) compared to other algorithms. Therefore, it can be concluded that the integration of the NN algorithm with Sample Bootstrapping and Weighted PCA produces better accuracy than other algorithms

Penyakit jantung merupakan salah satu penyakit dengan angka kematian tertinggi di negara maju bahkan dunia. Penyakit jantung dapat mengancam jiwa jika tidak ditangani dengan serius. Jumlah penderita penyakit jantung meningkat setiap tahunnya. Penyakit jantung dapat disebabkan oleh beberapa faktor, yang utama adalah konsumsi alkohol berlebihan, kebiasaan merokok, dan faktor keturunan. Penelitian ini bertujuan untuk memprediksi dan mencegah penyakit jantung sejak dini menggunakan algoritma pembelajaran mesin, yaitu regresi logistik. Data yang digunakan untuk pelatihan dan pengujian algoritma regresi logistik sebanyak 1.190 data, yang terbagi menjadi 80% data pelatihan dan 20% data pengujian. Hasil pengujian menunjukkan bahwa model dapat memprediksi dengan akurasi sebesar 86%. Setelah model dibuat, model tersebut diimplementasikan ke dalam situs web. Penelitian ini diharapkan dapat berkontribusi pada diagnostik yang dapat membantu deteksi dini penyakit jantung.

Hubungan antara variabel-variabel independen dengan variabel-variabel dependen kemungkinandipengaruhi oleh variabel-variabel lain, salah satu diantaranya adalah variabel moderating. Variabelmoderating ini dapat memperkuat atau memperlemah hubungan antara variabel independen dan variabeldependen. Sifat atau arah hubungan antara variabel-variabel independen dengan variabel-variabel dependendapat positif atau negatif tergantung pada pada variabel moderating. Ada beberapa uji untuk untuk mengujipengaruh variabel moderating ini, diantaranya adalah Moderated Regression Analysis (MRA). ModeratedRegression Analysis (MRA) merupakan aplikasi khusus regresi berganda linear dimana dalam persamaanregresinya mengandung unsur interaksi (perkalian dua atau lebih variabel independen).