Mean Reversion Strategy: Betting on Price Normalcy
Mean reversion is based on the concept that prices, or other economic indicators, tend to revert to their historical average or mean over time. In the context of trading, a mean reversion strategy involves identifying and taking positions in assets that have deviated significantly from their historical average, anticipating that they will revert to that average.
Understanding Mean Reversion
At the heart of mean reversion is the idea that extreme up or down movements in price are likely to revert to the mean. This strategy often applies to assets that have inherent value, such as stocks, where prices can deviate due to short-term market sentiment but ultimately return to their intrinsic value.
Characteristics of Mean Reversion
- Cyclical Patterns: Assets that exhibit cyclical or oscillating patterns are often prime candidates for mean reversion strategies.
- Short to Medium-term: This strategy often plays out over shorter time frames than trend-following strategies. Weeks to months is common.
- Contrarian: Mean reversion can be seen as contrarian because it often involves buying assets that are out of favor (or selling assets that are in favor) with the broader market.
Tools and Indicators in Mean Reversion
- Bollinger Bands: These envelop price movements, with deviations from the middle band (a moving average) suggesting potential overbought or oversold conditions.
- Relative Strength Index (RSI): An oscillator that measures the speed and change of price movements. RSI readings above 70 indicate overbought conditions, while readings below 30 indicate oversold conditions.
- Moving Averages: Comparing short-term moving averages with long-term ones can help identify significant deviations from the mean.
- Standard Deviation: A statistical measure of volatility, it helps determine the extent of the deviation from the mean.
Risks in Mean Reversion Trading
While mean reversion strategies can be profitable, there are risks to consider:
- Extended Deviations: Prices can deviate from their mean for longer periods than expected, leading to potential losses.
- Changing Fundamentals: A significant change in an asset's fundamentals might mean it will not revert to its historical mean.
- Over-reliance on Past Data: Historical mean might not always be indicative of future performance, especially in changing market conditions.
Conclusion
Mean reversion trading is based on the belief in the natural equilibrium of asset prices. While historical patterns suggest that prices tend to revert to their mean, it's crucial for traders to combine technical indicators with a keen sense of market sentiment and fundamentals. As with all trading strategies, thorough research, back-testing, and risk management are essential for consistent success.