Potato Price Forecasting with Holt-Winters and ARIMA Methods: A Case Study

In this paper, the first study using exponential smoothing methods and the Box-Jenkins method for forecasting consumer potato prices in Turkey is conducted. The exponential smoothing methods include the Holt-Winters multiplicative (HWM) method and the Holt-Winters additive (HWA) method. This study explores the application of the Holt-Winters approach to time series data of consumer potato prices covering the period from January 1st, 2005 to July 31st, 2019. The data were obtained from the database of the Turkish Statistical Institute. The paper explores and forecasts the trend of potato prices from August to December 2019. The results illustrate that the ARIMA method achieves good consumer potato price forecasting accuracy according to the mean absolute percentage error (MAPE), the root mean square error (RMSE) and the mean absolute deviation (MAD). As a result, the forecasted values from August 2019 to December 2019 are calculated in this paper via these methods.