Concepts of Multi-Factor Risk Models
masterThe attribution analysis is based on the multi-factor risk model theory, which posits that stock returns are driven by common factors. The model decomposes returns into:
- Style Factors: Factors affecting returns such as size, growth, leverage, etc.
- Industry Factors: Returns associated with specific industry sectors.
- Country Factors: The overall market movement affecting all stocks in the same market.
- Specific Returns (Idiosyncratic Returns): The portion of returns that cannot be explained by the common factors (e.g., company-specific news, management decisions).
The mathematical representation of stock return $R_i$ is: $R_i = \text{Country Factor Return} + \sum \text{Style Factor Returns} + \sum \text{Industry Factor Returns} + \text{Specific Return}$