In the current digital age, fraud detection has grown progressively more important, where large-scale transactions are processed in real time, posing challenges for conventional detection methods. The proliferation of big data in financial systems has introduced complexities in analyzing massive, high-dimensional datasets, necessitating advanced techniques to ensure accurate and timely fraud
... [Show full abstract] detection. These approaches do not solve the problems of imbalance and redundancy of data in the traditional way. This research work presents an enhanced fraud detection framework using Bi-directional Long Short-Term Memory (Bi-LSTM) networks for detecting anomalies and marking possibly fraudulent transactions. The parameters of the proposed model are then optimized through Grey Wolf Optimization (GWO) for better prediction of parameters and reduction of computational time. The suggested model is trained and validated using the Kaggle Credit Card Fraud Detection dataset. Principal Component Analysis (PCA) is the dimensionality reduction technique utilized for high-dimensional data. Additionally, samples of the minority classes (fraudulent transactions) are synthesized using the Synthetic Minority Over-Sampling Technique (SMOTE), which is used to rectify the dataset's imbalance. First, the Big Bang Big Crunch (BBBC) algorithm is used to choose the optimum input features for the Bi-LSTM model. Significant improvements in fraud detection are also demonstrated by the suggested GWO-Bi-LSTM framework; the quantitative outcomes include 96.2% recall, 97.4% accuracy, 95.9% precision, and 96.0% F1-score. These results are better than the baseline methods, which proves the efficiency of the proposed hybrid technique in identifying fraudulent transactions. The incorporation of state-of-the-art optimization techniques, feature reduction and deep learning models offers a reliable solution for fraud detection in big data business transactions.