9 Jul, 2025
Does Stat Arb (Pairs Trading) Work in Crypto?
Pairs trading—also known as statistical arbitrage—has long been a cornerstone of institutional equity strategies. Its transition into cryptocurrency markets promises a similarly market‐neutral path to alpha but demands rigorous adaptation to crypto’s unique characteristics. This article presents an overview of the mechanics underpinning crypto pairs trading, surveys leading empirical studies by name, categorizes the main methodological approaches, and evaluates why and how the strategy continues to deliver in today’s digital‐asset landscape.

Mechanics of Crypto Pairs Trading

At its core, pairs trading constructs a relative‐value position by longing one asset and shorting another when their price relationship deviates from historical norms. In cryptocurrencies, the typical workflow comprises:

  1. Identification of Cointegrated Pairs
    Institutional practitioners employ formal cointegration tests (e.g., Johansen trace or Bounds tests) to confirm a stable long‐run equilibrium between log‐price series. Only pairs with test statistics exceeding critical thresholds (p < 0.05) are shortlisted .
  2. Spread Construction and Hedge Ratio Estimation
    A linear regression of the form: ln⁡PA,t=α+β ln⁡PB,t+εt \ln P_{A,t} = α + β\,\ln P_{B,t} + ε_tlnPA,t​=α+βlnPB,t​+εt​yields the hedge ratio βββ and residual spread εtε_tεt​. Advanced desks favor dynamic estimation—via a Kalman filter state‐space model—which allows βtβ_tβt​ to evolve and adapt to regime shifts .
  1. Signal Generation and Execution
    Entry signals arise when the standardized spread St=εt/σ(ε)S_t = ε_t/\sigma(ε)St​=εt​/σ(ε) breaches the 5th or 95th percentiles of its empirical distribution. Exit occurs upon reversion to the mean or when a predetermined time stop (e.g., 30–60 days) is reached, protecting against persistent structural breaks.
  2. Risk and Cost Management
    Execution models integrate real‐time liquidity metrics, funding‐rate forecasts for perpetual derivatives, and granular slippage estimates. Positions are volatility‐scaled, with diversified clusters to contain drawdowns.

Types of Pairs Methodologies

Institutional crypto desks leverage several distinct approaches to identify and trade pairs, each with its own signal characteristics and implementation demands:

  1. Distance- or Z-Score-Based Pairs
    • Mechanics: Normalize two price series (e.g., divide each by its rolling mean), compute the difference DtD_tDt​, and calculate the Z-score Zt=(Dt−μD)/σDZ_t = (D_t – \mu_D)/\sigma_DZt​=(Dt​−μD​)/σD​.
    • Signals: Enter when ∣Zt∣|Z_t|∣Zt​∣ exceeds a threshold (commonly 1.5–2.0) and exit when ZtZ_tZt​ returns toward zero.
    • Pros/Cons: Simple to implement; vulnerable to regime shifts and false breaks in volatile markets .
  2. Cointegration-Based Pairs
    • Mechanics: Test for a long-run equilibrium via Engle–Granger or Johansen frameworks. Estimate a static hedge ratio βββ from the cointegrating regression and trade residuals.
    • Signals: Entry/exit defined by residual deviations from zero, often in standard-deviation units.
    • Pros/Cons: Filters out spurious correlations; may lag when true relationships evolve .
  3. Kalman Filter-Enhanced Pairs
    • Mechanics: Model the hedge ratio βtβ_tβt​ as a random walk in a state-space representation, updating estimates in real time using the Kalman filter.
    • Signals: Similar residual-based triggers, but with dynamically adjusted βtβ_tβt​.
    • Pros/Cons: Adapts to regime shifts, reducing large drawdowns; requires more computational infrastructure .
  4. Quantile-Based Spread Trading
    • Mechanics: Empirically determine extreme percentiles (e.g., 5th/95th) of the spread’s historical distribution rather than assuming normality.
    • Signals: Entry when spread breaches these quantiles; exit when it reverts inside.
    • Pros/Cons: Robust to fat tails and asymmetry; needs large data samples for reliable quantile estimation.
  5. Copula-Augmented Pairs
    • Mechanics: After establishing a linear relationship, fit a copula to model joint tail dependencies between two assets.
    • Signals: Identify simultaneous extreme moves beyond linear residuals, capturing non-linear co-movements.
    • Pros/Cons: Enhances signal quality for tail events; introduces model complexity and estimation risk .
  6. Machine Learning & Graph-Matching Selection
    • Mechanics: Represent each token as a node in a graph; edge weights derive from cointegration strength or other features. Use algorithms (e.g., maximum-weight matching, genetic algorithms) to select disjoint, high-potential pairs.
    • Signals: Follow any of the above entry/exit rules once pairs are chosen.
    • Pros/Cons: Optimizes portfolio-level objectives; requires careful regularization to avoid overfitting.

Empirical Evidence: Named Studies

A growing body of research confirms that disciplined crypto pairs strategies can rival their equity counterparts in risk-adjusted returns:

  • Fil & Kristoufek (2020) filtered 181 Binance-listed tokens to 26 liquid names and applied daily and hourly cointegration methods, achieving a net Sharpe ratio of 1.02 after realistic trading costs .
  • SSRN’s “Pairs Trading in the Cryptocurrency Market: A Long-Short Story” (2024) examined the top 100 coins (2019–2023), reporting a 14.3% annualized return, 0.93 Sharpe, and peak drawdowns near 15.7% .
  • Tadi & Witzany (2023) introduced copula models to capture tail dependencies, boosting Bitcoin–Ethereum pair performance to a gross Sharpe of 1.24 and a net Sharpe of 1.10 .
  • In Acta Oeconomica (2025), Mahajan & Chandra used an NSGA-II genetic algorithm to optimize pair selection, delivering 12.6% annualized returns and a 1.15 Sharpe while cutting turnover by 24% .

Why Crisis Alpha Emerges

During periods of extreme volatility—such as the March 2020 crash—crypto markets exhibit exaggerated price swings and temporary liquidity imbalances. These conditions accentuate mean reversion for two reasons:

  1. Transient Dislocations: Aggressive liquidations in one token can outpace moves in its pair, creating exploitable gaps as market-makers and algorithmic liquidity providers recalibrate quotes.
  2. Synchronous Overreaction: Panic-driven selloffs across correlated assets magnify spread deviations. As sentiment normalizes, the relative valuation gap tends to snap back rapidly.

Institutional Considerations & Advanced Topics

  • Ongoing Validity Monitoring: Automated triggers for rolling cointegration tests and residual-volatility spikes ensure prompt model recalibration.
  • On-Chain Data Integration: Incorporating metrics such as token flows between exchanges or DeFi total value locked can refine entry timing.
  • Cross-Asset Extensions: Some desks layer crypto pairs with commodity or FX pairs (e.g., BTC vs. oil-linked currencies), broadening alpha sources while maintaining market neutrality.
  • Governance & Risk Controls: Governance frameworks encompassing stop-loss thresholds, capital limits per pair, and third-party audits safeguard model integrity.

Conclusion

Named empirical evidence—from Fil & Kristoufek’s Binance deep-dive to Tadi & Witzany’s copula augmentations and Mahajan & Chandra’s genetic-algorithm optimizations—demonstrates that statistical arbitrage remains a potent, market-neutral strategy in cryptocurrencies. By selecting pairs through rigorous cointegration and graph-matching techniques, employing dynamic hedge ratios, and integrating robust risk controls, institutional traders can continue to extract alpha from crypto’s distinct market structure.

References

  • Fil, M., & Kristoufek, L. (2020). Profitability of Pairs Trading in Crypto Markets: Evidence from Binance.
  • SSRN. (2024). Pairs Trading in the Cryptocurrency Market: A Long-Short Story.
  • Tadi, M., & Witzany, J. (2023). Copula-Based Trading of Cointegrated Cryptocurrency Pairs.
  • Mahajan, D., & Chandra, A. (2025). NSGA-II-Based Crypto Pairs Selection. Acta Oeconomica.
  • Amberdata Blog. (2024). Crypto Pairs Trading: Empirical Results and Performance Analysis.