Wavelet Denoising and Model Parsimony in High-Frequency Momentum Strategies: Evidence from China’s ChiNext Market
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Abstract
This study introduces a sophisticated dual-denoising framework for high-frequency momentum strategies in China's ChiNext market, integrating wavelet-based temporal filtering with isolation forest cross-sectional anomaly detection. Utilizing a comprehensive dataset of over 2 million daily observations from January 2016 to November 2025, the results demonstrate that wavelet denoising achieves exceptional efficacy for turnover series with a mean Signal-to-Noise Ratio improvement of 10.7 dB, while isolation forest robustly identifies anomalous stocks characterized by excessive trading activity and distorted risk-return profiles. Empirical results reveal that parsimonious models with wavelet denoising consistently outperform complex alternatives, with linear-kernel Support Vector Machines achieving Sharpe ratios of 0.1132 in long portfolios and 0.0649 in long-short implementations. Contrary to conventional wisdom, simpler architectures demonstrate superior performance, with single-layer neural networks and regularized linear models surpassing deeper architectures across all denoising configurations. The methodology demonstrates remarkable regime invariance, maintaining consistent performance during both low-volatility and high-volatility market states. These findings establish wavelet denoising as a critical preprocessing technique for high-frequency financial data and challenge assumptions about the necessity of complex models in quantitative finance, providing computationally efficient approaches suitable for both institutional and retail investors.
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References
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Cite This Article
TY - JOUR AU - Yi, Yingnan PY - 2026 DA - 2026/04/10 TI - Wavelet Denoising and Model Parsimony in High-Frequency Momentum Strategies: Evidence from China’s ChiNext Market JO - ICCK Transactions on Machine Intelligence T2 - ICCK Transactions on Machine Intelligence JF - ICCK Transactions on Machine Intelligence VL - 2 IS - 3 SP - 172 EP - 189 DO - 10.62762/TMI.2025.742127 UR - https://www.icck.org/article/abs/TMI.2025.742127 KW - momentum investing KW - wavelet denoising KW - portfolio management KW - chiNext market KW - machine learning KW - financial signal processing AB - This study introduces a sophisticated dual-denoising framework for high-frequency momentum strategies in China's ChiNext market, integrating wavelet-based temporal filtering with isolation forest cross-sectional anomaly detection. Utilizing a comprehensive dataset of over 2 million daily observations from January 2016 to November 2025, the results demonstrate that wavelet denoising achieves exceptional efficacy for turnover series with a mean Signal-to-Noise Ratio improvement of 10.7 dB, while isolation forest robustly identifies anomalous stocks characterized by excessive trading activity and distorted risk-return profiles. Empirical results reveal that parsimonious models with wavelet denoising consistently outperform complex alternatives, with linear-kernel Support Vector Machines achieving Sharpe ratios of 0.1132 in long portfolios and 0.0649 in long-short implementations. Contrary to conventional wisdom, simpler architectures demonstrate superior performance, with single-layer neural networks and regularized linear models surpassing deeper architectures across all denoising configurations. The methodology demonstrates remarkable regime invariance, maintaining consistent performance during both low-volatility and high-volatility market states. These findings establish wavelet denoising as a critical preprocessing technique for high-frequency financial data and challenge assumptions about the necessity of complex models in quantitative finance, providing computationally efficient approaches suitable for both institutional and retail investors. SN - 3068-7403 PB - Institute of Central Computation and Knowledge LA - English ER -
@article{Yi2026Wavelet,
author = {Yingnan Yi},
title = {Wavelet Denoising and Model Parsimony in High-Frequency Momentum Strategies: Evidence from China’s ChiNext Market},
journal = {ICCK Transactions on Machine Intelligence},
year = {2026},
volume = {2},
number = {3},
pages = {172-189},
doi = {10.62762/TMI.2025.742127},
url = {https://www.icck.org/article/abs/TMI.2025.742127},
abstract = {This study introduces a sophisticated dual-denoising framework for high-frequency momentum strategies in China's ChiNext market, integrating wavelet-based temporal filtering with isolation forest cross-sectional anomaly detection. Utilizing a comprehensive dataset of over 2 million daily observations from January 2016 to November 2025, the results demonstrate that wavelet denoising achieves exceptional efficacy for turnover series with a mean Signal-to-Noise Ratio improvement of 10.7 dB, while isolation forest robustly identifies anomalous stocks characterized by excessive trading activity and distorted risk-return profiles. Empirical results reveal that parsimonious models with wavelet denoising consistently outperform complex alternatives, with linear-kernel Support Vector Machines achieving Sharpe ratios of 0.1132 in long portfolios and 0.0649 in long-short implementations. Contrary to conventional wisdom, simpler architectures demonstrate superior performance, with single-layer neural networks and regularized linear models surpassing deeper architectures across all denoising configurations. The methodology demonstrates remarkable regime invariance, maintaining consistent performance during both low-volatility and high-volatility market states. These findings establish wavelet denoising as a critical preprocessing technique for high-frequency financial data and challenge assumptions about the necessity of complex models in quantitative finance, providing computationally efficient approaches suitable for both institutional and retail investors.},
keywords = {momentum investing, wavelet denoising, portfolio management, chiNext market, machine learning, financial signal processing},
issn = {3068-7403},
publisher = {Institute of Central Computation and Knowledge}
}
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