Quantum Temporal Convolutional Neural Networks for Cross-Sectional Equity Return Prediction: A Comparative Benchmark Study
Financial time series exhibit high noise levels, frequent regime shifts, and pose challenges for classical models due to limited generalization. To address these, this paper proposes the Quantum Temporal Convolutional Neural Network (QTCNN), which integrates a classical multi-scale temporal encoder with a parameter-efficient, trainable quantum convolutional circuit. Leveraging quantum superposition and entanglement, QTCNN enhances feature representation while mitigating overfitting. We evaluate the model on cross-sectional stock return prediction using JPX Tokyo Stock Exchange data and construct long–short portfolios for empirical validation. Out-of-sample testing yields a Sharpe ratio of 0.538—72% higher than the best classical baseline—demonstrating substantial improvements in prediction stability and generalization. This work pioneers the application of lightweight, differentiable quantum convolution to high-frequency quantitative forecasting, establishing a novel paradigm and providing empirical validation for practical quantum–classical hybrid modeling in real-world financial settings.