FORECAST OF THE PRICE OF FRESH FRUIT BUNCHES OF OIL PALM IN BENGKULU PROVINCE FOR THE PERIOD 2021–2024
Keywords:
FFB price, forecasting, oil palm, price volatility, weighted moving averageAbstract
Fresh fruit bunch (FFB) prices are a principal source of income vulnerability for independent smallholders. This study maps FFB price volatility in Bengkulu Province, evaluates the accuracy of the three-period weighted moving average (WMA) method, and assesses the stability of that accuracy under normal and shock conditions. Monthly data on FFB prices from January 2021 to May 2024 (41 observations) were obtained from the Ministry of Trade's SP2KP system and Statistics Indonesia of Bengkulu Province. Accuracy was measured using MAD, MSE, RMSE, MAPE, and MPE, benchmarked against a naïve model via Theil's inequality coefficient, and validated by a hold-out test. The results show a mean price of IDR. 2,312.76/kg with a coefficient of variation of 19.46%; volatility peaked in 2022 (CV 34.49%), the deepest monthly decline being 52.63% in July 2022. The best weight combination, 9:1:1, yielded a MAPE of 9.56% and RMSE of IDR 346.16, outperforming equal weights (13.70%) and the conventional 3:2:1 scheme (11.86%). Nevertheless, all specifications produced Theil U values exceeding unity, failing to surpass the naive benchmark. Accuracy was also unstable across subperiods, at 7.13% during recovery but 34.39% during the shock. WMA is therefore defensible as a smoothing and short-run reference-price instrument but inadequate as an early-warning system.
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