Research on the Prediction Method of Monthly Hidden Danger Quantity in Coal Mine Based on BP Neural Network Periodic Combination Model

Table 5

Accuracy inspection level table.

Level	Postdifference ratio C	Small error probability
1	≤0.35	≥0.95
2	≤0.50	≥0.80
3	≤0.65	≥0.70
4	>0.65	<0.70

Note. The model’s accuracy level .