Fama-French Three Factor Strategy
Model market, size, and value exposures in a systematic equity portfolio
Fama-French Three Factor Strategy is a systematic factor portfolio template that scores securities with market, size, and value factor exposures, converts ranks into controlled positions, and manages factor crowding with market beta band, size-value exposure caps, and factor drawdown controls. - Fama and French
本策略作為教育示例提供，其靈感來自常見的公共技術分析概念和參考材料。僅用於研究和產品演示，不構成投資建議。
策略適用性
風險: HIGH
✅ 適用於
❌ 避免使用於
Multi-factor systems can look diversified while still sharing hidden exposures; market beta band, size-value exposure caps, and factor drawdown controls must be measured explicitly.
問: What is the core idea behind Fama-French Three Factor Strategy?
The strategy combines market, size, and value factor exposures, ranks securities using expected exposure to market beta, SMB, and HML factors, enters when the portfolio earns targeted size and value exposure after market-risk controls, and exits when factor exposure leaves the target range or the rebalance model replaces the holding.
問: When does Fama-French Three Factor Strategy usually fail?
It usually fails when factor signals become crowded, accounting inputs are biased, turnover overwhelms the edge, or the chosen factors stop being rewarded.
問: How should Fama-French Three Factor Strategy be backtested?
Backtest it with point-in-time fundamentals, delisting-aware universes, realistic rebalance calendars, transaction costs, turnover limits, and exposure attribution.
此策略的運作方式
從市場解讀到交易管理的 5 階段決策流程
1
Factor Universe
Define eligible securities
Screen the universe before applying market, size, and value factor exposures
Remove names with unreliable fundamentals, stale prices, low liquidity, or survivorship-biased data
Normalize accounting dates, market caps, sectors, and currency exposure before ranking
2
Factor Scoring
Rank expected return drivers
Compute expected exposure to market beta, SMB, and HML factors with point-in-time inputs
Use beta drift, sector imbalance, and factor multicollinearity filters to reject crowded or structurally weak factor exposure
Check whether factor signals remain stable after sector, size, and liquidity constraints
3
Portfolio Construction
Balance return and exposure
Convert scores into weights without letting one factor dominate the book
Limit unintended beta, sector, country, and capitalization tilts
Verify that turnover is economically justified after costs and tax assumptions
4
Rebalance
Enter, rotate, and remove
Enter when R_i - R_f = alpha + beta_m MKT + beta_s SMB + beta_v HML produces a tested positive score
Prefer entries where the portfolio earns targeted size and value exposure after market-risk controls
Exit or reduce exposure when factor exposure leaves the target range or the rebalance model replaces the holding
5
Exposure Control
Stress-test factor risk
Define market beta band, size-value exposure caps, and factor drawdown controls before the first rebalance
Stress factor crashes, valuation regime shifts, stale fundamentals, and liquidity exits
Stop deploying the model when live factor behavior diverges from the tested sample
策略元件參考
- Fama-French Three Factor Strategy
- Fama-French Three Factor Strategy is a systematic factor portfolio template that scores securities with market, size, and value factor exposures, converts ranks into controlled positions, and manages factor crowding with market beta band, size-value exposure caps, and factor drawdown controls.
- Fama-French Three Factor Strategy Market Suitability
- The Fama-French Three Factor Strategy strategy works best in Broad liquid universes where market, size, and value factor exposures can be measured with point-in-time data.. Portfolio workflows that can rebalance systematically while controlling turnover, sectors, beta, and liquidity.. Regimes where factor premia are diversified rather than concentrated in one crowded trade.. Traders should avoid using this strategy in Small universes where factor rankings are dominated by accounting noise or stale prices.. Crowded factor unwind periods where many strategies hold similar long and short books.. Backtests with look-ahead fundamentals, missing delisting data, or unrealistic execution assumptions.. The risk level is categorized as HIGH. Multi-factor systems can look diversified while still sharing hidden exposures; market beta band, size-value exposure caps, and factor drawdown controls must be measured explicitly.
- What is the core idea behind Fama-French Three Factor Strategy?
- The strategy combines market, size, and value factor exposures, ranks securities using expected exposure to market beta, SMB, and HML factors, enters when the portfolio earns targeted size and value exposure after market-risk controls, and exits when factor exposure leaves the target range or the rebalance model replaces the holding.
- When does Fama-French Three Factor Strategy usually fail?
- It usually fails when factor signals become crowded, accounting inputs are biased, turnover overwhelms the edge, or the chosen factors stop being rewarded.
- How should Fama-French Three Factor Strategy be backtested?
- Backtest it with point-in-time fundamentals, delisting-aware universes, realistic rebalance calendars, transaction costs, turnover limits, and exposure attribution.
- market, size, and value factor exposures
- market, size, and value factor exposures defines the return drivers the model attempts to harvest before portfolio constraints are applied. Formula: R_i - R_f = alpha + beta_m MKT + beta_s SMB + beta_v HML
- Point-in-Time Data
- Point-in-time data prevents the backtest from using financial statements or index membership information before it was actually available. Formula: Use known values only
- Eligible Universe
- The eligible universe defines which securities can be scored and traded, reducing noise from illiquid or incomplete records. Formula: Liquidity + data filters
- expected exposure to market beta, SMB, and HML factors
- expected exposure to market beta, SMB, and HML factors converts raw factor data into comparable scores that can drive weights, inclusions, and exclusions. Formula: Composite factor rank
- beta drift, sector imbalance, and factor multicollinearity filters
- beta drift, sector imbalance, and factor multicollinearity filters keeps the model from allocating to securities whose factor score is not robust enough for a live rebalance. Formula: Reject unstable exposure
- Sector Normalization
- Sector normalization reduces the chance that a factor score is just a disguised industry or market-cap bet. Formula: Rank within comparable groups
- the portfolio earns targeted size and value exposure after market-risk controls
- the portfolio earns targeted size and value exposure after market-risk controls turns factor ranking into an investable position only after the score clears the tested inclusion rule. Formula: Score crosses inclusion rule
- Weighting Rule
- The weighting rule converts selected securities into portfolio exposure while limiting concentration in any single name or factor. Formula: Score, equal, or risk weight
- Rebalance Calendar
- A fixed rebalance calendar prevents hindsight entries and makes turnover, data lag, and execution cost assumptions testable. Formula: Monthly or quarterly refresh
- Rank Decay Exit
- The rank decay exit removes or reduces securities when factor exposure leaves the target range or the rebalance model replaces the holding, keeping the portfolio aligned with current factor evidence. Formula: factor exposure leaves the target range or the rebalance model replaces the holding
- Turnover Budget
- A turnover budget stops small score changes from creating trades whose costs are larger than their expected factor benefit. Formula: Trade only if benefit > cost
- Exposure Drift
- Exposure drift rules force a rebalance when market movement changes beta, sector, or factor exposures beyond the tested limits. Formula: Rebalance when constraints break
- market beta band, size-value exposure caps, and factor drawdown controls
- market beta band, size-value exposure caps, and factor drawdown controls defines the explicit controls that stop a factor portfolio from becoming an unintended one-way exposure. Formula: Factor and portfolio limits
- Beta Control
- Beta control separates factor selection skill from simple market direction and keeps the strategy comparable across regimes. Formula: Portfolio beta within band
- Crowding Review
- Crowding review asks whether many investors may be holding the same factor portfolio, increasing drawdown risk during forced exits. Formula: Reduce shared crowded exposure