Measuring Spatial Integration in Tomato and Onion Markets of Pakistan: An Application of Error Correction Model in the Presence of Stationarity

This paper empirically evaluates the degree of integration among spatially separated markets using monthly wholesale real price series of tomato and onion from regional markets located in each of the four provinces of Pakistan. Unit root test indicates that the price series are stationary, and are represented as autoregressive model for each region. Results of the error correction model show that the markets of both tomato and onion are spatially integrated, however, the overall degree of integration in onion markets is relatively stronger than in tomato markets. This difference may be attributed to relatively lower degree of perishability in onion as compared to tomato.