Journal of Behavioral and Experimental Finance, cilt.49, 2026 (SSCI, Scopus)
This study constructs a Composite Investor Sentiment Index (CIST) integrating six behavioral and market-based proxies to examine how investor sentiment influences cryptocurrency returns and volatility. Using weekly data from March 2018-July 2023, we decompose sentiment into rational and irrational components via ARDL and analyze dynamic effects through VAR and impulse responses. The first principal component explains almost 70 % of total variance. Results show that rational sentiment exerts persistent, long-run effects on returns and volatility, while irrational sentiment causes short-lived volatility spikes. The findings advance behavioral finance by demonstrating that distinguishing cognitive from emotional investor reactions enhances understanding of cryptocurrency market behavior.