Nickel Price Forecast Based on the LSTM Neural Network Optimized by the Improved PSO Algorithm

Table 5

The Ljung–Box test results of the residual square sequence of the ARIMA(1, 1, 2).

Lag	AC	Q	-value
1.0	0.001880	0.000407	0.983911
2.0	−0.013717	0.022247	0.988938
3.0	0.240741	6.811112	0.078168
4.0	0.060478	7.243522	0.123565
5.0	0.006430	7.248456	0.202808
6.0	0.191994	11.688549	0.069289
7.0	0.073203	12.340164	0.089913
8.0	0.060502	12.78956	0.119298
9.0	0.048683	13.083349	0.158871
10.0	0.184445	17.341826	0.067134
11.0	0.111246	18.906318	0.062796
12.0	−0.011588	18.923464	0.090392