表 4. Test statistics and P-values of COP feature parameters test at P2 across different periods.

P2下各个时期的COP特征参数检验的检验值和P值

对比方式	轨迹移动长度	轨迹包络面积	左右动摇轨迹长	前后动摇轨迹长
Q1 vs Q2	W = 13，P = 0.042	W = 12，P = 0.034	W = 30，P = 0.518	W = 11，P = 0.026
Q1 vs Q3	W = 10，P = 0.020	W = 6，P < 0.01	W = 26，P = 0.339	W = 4，P < 0.01
Q2 vs Q3	W = 26，P = 0.034	W = 13，P = 0.042	W = 28，P = 0.423	W = 12，P = 0.034