Statistical Identification and Backtesting of Mean-Reverting Forex Pairs Using Augmented Dickey-Fuller and Hurst Exponent Methods for Algorithmic Trading
DOI:
https://doi.org/10.64807/z5z11q86Abstract
This study investigates the mean-reverting behavior of major and minor foreign exchange (forex) currency pairs using statistical time-series analysis methods. The foreign exchange market is among the most liquid and widely traded financial markets globally, yet understanding the statistical dynamics of currency pairs remains a critical challenge for the development of algorithmic trading strategies. The primary objective of this research is to determine which major and minor forex pairs exhibit mean-reverting characteristics through the application of the Augmented Dickey-Fuller (ADF) test and Hurst exponent analysis, using ten years of daily closing price data spanning from 2016 to 2025. The study covers 28 currency pairs, comprising 7 major and 21 minor pairs. Exotic pairs were excluded due to lower liquidity and wider bid-ask spreads that may distort statistical results. Data was retrieved via the Google Finance function and analyzed using Python. The ADF test was employed to assess stationarity, while the Hurst exponent quantified the degree of mean-reversion or persistence in the return series. Results from the ADF test indicated rejection of the unit root null hypothesis for all currency pairs at the 5% significance level, confirming that the log return series are stationary. Hurst exponent analysis further revealed that all pairs exhibit values well below 0.5, consistent with mean-reverting behavior. The convergence of both statistical methods provides robust evidence that the log return dynamics of the analyzed forex pairs follow mean-reverting processes. These findings suggest opportunities for developing quantitative and algorithmic trading strategies based on statistical arbitrage principles. Future research is recommended to incorporate transaction costs, out-of-sample backtesting, exotic pairs, and additional statistical methods to validate further and expand these results.
Keywords:
Mean Reversion, Augmented Dickey-Fuller, Hurst Exponent, Forex Algorithmic Trading, StationarityReferences
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