Prediction of Tuberculosis (TB) and Pneumonia Cases in East Java Province for 2025-2026 Using ARIMA

Abstract

This study forecasts annual counts of tuberculosis and pneumonia in East Java for 2025 and 2026 using ARIMA models fitted to provincial totals from 2017 to 2024. Time series processing included stationarity testing and second order differencing when required, model identification by ACF and PACF, parameter estimation, and model selection guided by AIC together with forecast accuracy metrics. The selected models were ARIMA(1,0,2) for tuberculosis and ARIMA(2,0,2) for pneumonia. Forecast evaluation produced MAPE 17.56 percent for tuberculosis and MAPE 5.86 percent for pneumonia indicating acceptable short term performance. Point forecasts for pneumonia are 86,948 cases in 2025 with 95 percent confidence interval 78,046 to 95,849 and 77,843 cases in 2026 with interval 68,193 to 87,492. Point forecasts for tuberculosis are 76,344 cases in 2025 with 95 percent confidence interval 36,628 to 116,060 and 66,635 cases in 2026 with interval 10,379 to 122,891.