AI-DRIVEN SENTIMENT AND VOLATILITY DYNAMICS: AN EGARCH ANALYSIS OF INDIAN AND EUROPEAN STOCK MARKETS
DOI:
https://doi.org/10.69980/88r7sk35Keywords:
EGARCH, Investor Sentiment, Artificial Intelligence, Volatility Modelling, behavioural finance, Leverage EffectAbstract
The increasing interconnectedness of global financial markets has heightened the need for advanced analytical frameworks capable of capturing investor behaviour, volatility dynamics, and the broader accounting information environment. This study examines the relationship between leverage, volatility, and stock market performance across major European (DAX, Euronext, FTSE, SMI) and Indian (NIFTY 50, SENSEX) indices over ten years, incorporating the COVID-19 pandemic as a structural shock through a dummy-variable approach. The analysis employs the EGARCH (1,1) model to estimate volatility asymmetry and leverage effects using daily return data, complemented by machine learning–based sentiment indicators to capture behavioural influences and their interaction with information asymmetry and disclosure environments. The empirical findings reveal the presence of volatility clustering and significant negative leverage effects across all indices, with stronger effects observed during the pandemic period. European markets exhibit higher volatility persistence, whereas Indian markets demonstrate faster mean reversion, reflecting differences in structural, behavioural, and informational dynamics. Regression and EGARCH results indicate that leverage significantly influences market volatility but has a limited effect on short-term performance. The COVID-19 pandemic emerges as a major structural break, contributing substantially to volatility across markets. AI-based sentiment indicators provide meaningful explanatory insights and are interpreted as external information signals influencing perceptions of financial reporting quality and disclosure credibility. This study contributes to the literature by integrating AI-driven sentiment analytics with econometric volatility modelling within the accounting information framework. The findings offer important implications for financial reporting, disclosure practices, and information asymmetry, benefiting portfolio managers, policymakers, and governance stakeholders.
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