Testing Weak-Form Informational Efficiency of the BSE Sensex: Using Weekly Data

The evidence suggests that market efficiency in India is not a static property but a dynamic one, influenced by regulatory changes, investor behavior, and macroeconomic shocks.This time-varying weak-form efficiency exhibited by Sensex is consistent with the Adaptive Market Hypothesis,as evidenced by stationarity, martingale property, no nonlinearity, and no predictability,while the short-term serial dependence, mean re-version, and structural volatility breaks create periods of inefficiency.

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