DETECTION OF SEASONAL COMPOSITION AND DETERMINATION OF THE SHAPE OF THE TIME SERIES OF THE MONTHLY PRICES OF THE CUCUMBER CROP IN BAGHDAD PROVINCE FOR THE PERIOD (2010-2015) AND FORECASTING USING THE SEASONAL TIME SERIES (SARIMA)

Abstract

The research aims to detect the seasonal phenomenon of the monthly prices of the cucumber crop in Baghdad City and for the period (January 2010 - December 2015), as well as the determined of the time series of the monthly prices of the cucumber crop follow the additive or multiplicative model. The research concluded that the monthly prices of cucumber crop contain a seasonal composition(seasonal variations), this confirms the nature of the pattern that the cucumber crop has been affected by the season to a large extent. The research concluded that there was a rise in the prices of the cucumber crop during certain months of the year. This is confirmed by the results of the research, which will be reflected in one way or another on lower prices in the months of high sales according to the law of supply and demand. Seasonal time series and autoregressive integrated moving average (SARIMA) models were used. The results showed that the appropriate and efficient model for representing the time series data for the monthly prices of the cucumber crop is the SARIMA double seasonal model (2.1.1) (0.1,1) 12. According to the estimation results of this model, the monthly prices of the cucumber crop were predicted at (60) observations and for the period (January 2016-December 2020). The results were consistent with those in the original time series. The research recommended the necessity of preventing import at peak time and the need to work on the development of laws and legislation to protect the local agricultural products from the importer as well as the imposition of taxes and customs duties on imported products and not to allow entry into Iraq in the peak season of production.