Akademik Veri Yönetim Sistemi
XVI International Scientific Agriculture Symposium “AGROSYM 2025”, Sarajevo, Bosna-Hersek, 2 - 05 Ekim 2025, ss.600, (Özet Bildiri)
Agricultural price volatility significantly affects farmers, consumers, and policymakers, particularly in emerging market economies. Licensed warehouse systems have been increasingly advocated as mechanisms to stabilize markets by providing secure storage and enhancing farmers' market access. This study evaluates the effectiveness of licensed warehouses in mitigating price volatility, specifically focusing on wheat, maize, and barley in Türkiye. Monthly price data were analysed using ARCH (1994 to 2023) and GARCH (January 2003 to April 2025) modelling approaches to assess volatility dynamics. Initial diagnostic tests validated the suitability of ARCH modelling, revealing significant autocorrelation and ARCH effects. The ARCH(1) model for wheat demonstrated high statistical significance of parameters, with the ARCH parameter (α₁=0.7891) indicating strong but transient volatility following shocks. Descriptive statistics further highlighted substantial susceptibility to market shocks, evident from the extremely high kurtosis, significant Jarque-Bera statistic, and positive skewness, suggesting occasional sharp spikes and a long-term downward price trend. Significant volatility episodes were particularly pronounced in September 1995 and July 2022, attributable to drought, policy uncertainty, speculative behaviour, inadequate market information, and geopolitical events. Further analysis employing a GARCH(1,1) model confirmed substantial persistence of volatility across wheat, maize, and barley, indicating prolonged price impacts following shocks. Notably, the licensed warehouse dummy variable showed no statistically significant effect on conditional volatility, suggesting limited direct influence. These findings imply that licensed warehouses alone are insufficient to counteract extreme market shocks. Nonetheless, their potential role in broader agricultural market stabilization warrants further exploration and targeted integration within comprehensive policies.