Short-Term Coalmine Gas Concentration Prediction Based on Wavelet Transform and Extreme Learning Machine

Table 2

Comparison of different prediction methods.

Method	MAE	MAPE	RMSE	NRMSE	Training time (s)	Testing time (s)
CART	0.0249	0.0622	0.0314	0.0470	0.0280	0.0084
BPNN	0.0194	0.0481	0.0241	0.0361	0.5531	0.0650
SVM	0.0193	0.0479	0.0239	0.0358	N/A	N/A
ELM	0.0189	0.0468	0.0237	0.0354	0.0063	0.0054
WELM	0.0049	0.0123	0.0061	0.0091	0.0155	0.0073