Detecting credit card fraud is a major challenge because fraudulent transactions represent only a small fraction of financial data. Traditional methods like SMOTE (Synthetic Minority Oversampling Technique) help balance datasets but can also introduce noise and make models over- fit, reducing their effectiveness. To tackle the issues that come with oversampling, we present the Enhanced Fraud Classifier with Tomek Links (EFC-Tomek) framework. This approach builds on the existing EFN-SMOTE but takes a different approach, using Tomek Links undersampling instead of SMOTE oversampling to balance the dataset. Our main goal is to improve data quality and enhance the model’s ability to detect fraud more accurately and effectively. To test EFC- Tomek, we used two real-world datasets: European cardholders and Loan Prediction. We evaluated its performance using a number of classifiers, such as Random Forest, eXtreme Gradient Boosting, Logistic Regression, Gradient Boosting, Artificial Neural Networks, and Support Vector Classifier. The results showed that EFC-Tomek improved fraud detection, with ANN achieving the highest accuracy on both datasets.

In the realm of financial security, the detection and prevention of credit card fraud has become paramount. With the ever-increasing reliance on digital transactions, the risk of fraudulent activities targeting credit card systems has grown significantly. To combat this, sophisticated techniques are required to swiftly identify and mitigate potential threats. Machine learning, a cornerstone of modern data analysis, has emerged as a powerful tool in this pursuit. By leveraging vast datasets and employing advanced algorithms, machine learning enables the automated scrutiny of transactions, distinguishing between legitimate and fraudulent activities with remarkable precision. This paper introduces an intelligent method for credit card fraud detection that relies on Competitive Swarm Optimization (CSO) and Random Weight Network (RWN). Additionally, the system includes an automated hybrid feature selection capability to identify the most pertinent features during the detection process. The experimental outcomes validate that this system can attain outstanding results in G-Mean, RUC, and Recall values.

Credit card fraud poses a significant challenge for both consumers and organizations worldwide, particularly with the increasing reliance on credit cards for financial transactions. Therefore, it is crucial to establish effective mechanisms to detect credit card fraud. However, the uneven distribution of instances between the two classes in the credit card dataset hinders traditional machine learning techniques, as they tend to prioritize the majority class, leading to inaccurate fraud pre- dictions. To address this issue, this paper focuses on the use of the Elbow Fuzzy Noise Filtering SMOTE (EFN-SMOTE) technique, an oversampling approach, to handle unbalanced data. EFN-SMOTE partitions the dataset into multiple clusters using the Elbow method, applies noise filtering to each cluster, and then employs SMOTE to synthesize new minority instances based on the nearest majority instance to each minority instance, thereby improving the model’s ability to perceive the decision boundary. EFN-SMOTE’s performance was evaluated using an Artificial Neural Network model with four hidden layers, resulting in significant improvements in classification performance, achieving an accuracy of 0.999, precision of 0.998, sensitivity of 0.999, specificity of 0.998, F-measure of 0.999, and G-Mean of 0.999.