Econometric Analysis of the Effect of Price Dynamics of Selected Food Crops on Food Security in Nigeria

This study analyzed the dynamics and volatility of selected staple food crop prices and their effect on food security in Nigeria using monthly data from January 1980 to November 2025. The study focused on three major staple crops—maize, rice, and cowpea—due to their importance in household consumption and national food security. The Augmented Dickey-Fuller Test (ADF)and the Generalized Autoregressive Conditional Heteroskedasticity (GARCH) Model were employed to examine stationarity and volatility dynamics of the selected crop prices. The ADF test results revealed that all price series were non-stationary at level but became stationary after first differencing, indicating integration of order one, I (1). The ARCH-LM tests confirmed the presence of ARCH effects in all crop prices, justifying the use of the GARCH (1,1) model. The empirical findings revealed significant differences in volatility persistence among the selected crops. Maize prices exhibited the highest volatility persistence with a persistence parameter (α + β) of 0.9605 and a volatility half-life of approximately 17.2 months, indicating prolonged effects of market shocks. Cowpea prices also displayed high volatility persistence with a persistence coefficient of 0.9057 and a half-life of about 7 months, suggesting strong responsiveness to short-run shocks. Rice prices, however, showed relatively moderate volatility persistence with a persistence parameter of 0.5887 and a shorter half-life of 1.3 months, indicating faster market adjustment and greater stability. Diagnostic tests confirmed the adequacy and robustness of the estimated models, as no residual ARCH effects or serial correlation were detected. The study concludes that staple food price volatility constitutes a major threat to food security in Nigeria, particularly for maize and cowpea whose prices are highly sensitive to economic, climatic, and structural shocks. The study recommends strengthening strategic grain reserves, improving rural infrastructure, promoting climate-smart agriculture, ensuring macroeconomic stability, and enhancing market information systems to reduce food price volatility and improve food security outcomes in Nigeria.