Forecasting Price of Small Cardamom in Southern India Using ARIMA Model

Small cardamom is one of the most popular and expensive spices in India. Two top constraints as judged in the year 2019 were labour shortage during production and price fluctuations during the marketing of this crop. This work is an attempt to forecast the price of small cardamom by using its price data from May 2015 to December 2019. It is evident from the data that there is no seasonality in the crop price data during that period. So, Sen’s slope estimator and Mann–Kendall tests are employed to estimate the price trend, and it is found that there is an increasing trend with a magnitude of 0.429. Thus, ARIMA (Autoregressive Integrated Moving Average) model is used to predict the price of the crop for the 2020 period, where it is applied different combinations of (p, d, q) values based on ACF (Auto-Correlation Function) and PACF (Partial Autocorrelation Function) plots. By using standard criteria such as RMSE (Root Mean Square Error), MAPE (Mean Absolute Percentage Error), and MAD (Mean Absolute Deviation), the accuracy of the selected models was assessed. The ARIMA (3,1,3) model performed better in forecasting the prices for small cardamom in southern India. COVID-19 (2019–2020) had a significant impact on the price of small cardamom in southern India, where the price has more fluctuations with a variance of 639,147.93 compared to the forecasted price variance of 65,199.97.