University of Tehran Iranian Economic Review 1026-6542 30 2 2026 06 01 The Impact of Investment Manager Expertise on Mutual Fund Performance in Indonesian Dynamic Market Conditions 600 615 97163 10.22059/ier.2024.373631.1007962 EN Alfi Syahri Faculty of Economics and Business, Diponegoro University, Semarang, Indonesia. 0009-0008-5065-4228 Irene Rini Demi Pangestuti Faculty of Economics and Business, Diponegoro University, Semarang, Indonesia. 0000-0003-3008-0972 Journal Article 2024 03 10 This study investigates the performance of 29 equity mutual funds in Indonesia, focusing on the influence of investment-manager expertise and market conditions. Using primary data sourced from Infovesta, we uncover a significant relationship between market conditions and fund performance. Our analysis reveals a statistically significant probability of changes in market conditions, with a calculated probability of 0.000, indicating a rare occurrence, less than 5% of the time. The coefficient value of 1.563714 further strengthens this relationship, indicating a substantial impact of market conditions on fund performance and supporting the acceptance of our third hypothesis. We find that bullish and bearish market conditions, representing rising and declining stock markets respectively, have a profound effect on equity mutual fund performance. Specifically, during bullish phases, fund performance improves, while in bearish market conditions, it declines. These results highlight the complex interplay between market dynamics and fund performance, underscoring the importance of skilled management in navigating market fluctuations effectively. Our findings contribute to the refinement of investment strategies, offering insights for achieving enhanced performance in dynamic market environments and advancing the discourse on effective portfolio management strategies. Market Sentiment Market timing skill mutual fund Mutual Fund Performance stock selection https://ier.ut.ac.ir/article_97163_d2e30fa59051e577818fdfe04334f963.pdf