Dynamic Beta Estimation with Kalman Filter - Quant Researcher Interview Question
Difficulty: Hard
Category: machine_learning
Asked at: Jane Street, HRT, Interactive Brokers, QuantConnect, Citadel Securities, AQR Capital Management, WorldQuant, Millennium
Topics: quantitative finance, kalman filter, time series, beta, linear algebra
Problem Description
The Capital Asset Pricing Model (CAPM) traditionally assumes a constant beta, but in dynamic markets, a stock's sensitivity to market movements fluctuates due to changing business environments and leverage. The Kalman Filter provides a recursive, optimal estimation method for tracking these time-varying parameters by updating state estimates with new noisy measurements. This approach is essential in quantitative finance for adaptive hedging, risk management, and pairs trading strategies.
Task
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