Forecasting China’s per Capita Living Energy Consumption by Employing a Novel DGM (1, 1, t^α) Model with Fractional Order Accumulation

Table 2

Metrics for evaluating effectiveness of the models.

Indicator	Formula
The absolute percentage error (APE)
The mean absolute percentage error (MAPE)
The mean absolute error (MAE)
The mean squares error (MSE)
The root mean squares percentage error (RMSPE)
The index of agreement (IA)
The correlation coefficient (R)