GRR 再生性为零？

A
Sample # 1st Trial 2nd Trial 3rd Trial
1 38.00 38.06 37.98
2 38.04 37.96 38.00
3 38.02 38.00 38.04
4 38.06 38.02 37.98
5 38.00 37.98 37.96
6 37.96 37.96 37.97
7 37.98 37.98 38.00
8 38.00 38.00 38.05
9 37.95 38.00 38.02
10 37.98 37.99 38.00

B
1st Trial 2nd Trial 3rd Trial
38.0200 38.0000 38.0400
38.0600 38.0200 37.9800
37.9800 37.9800 38.0000
38.0000 38.0000 38.0500
37.9500 38.0000 38.0200
38.0000 38.0600 37.9800
38.0400 37.9600 38.0000
38.0200 38.0000 38.0400
38.0600 38.0200 37.9800
38.0000 37.9600 37.9600

C
37.9500 38.0000 38.0200
38.0000 38.0600 37.9800
38.0200 38.0000 38.0400
38.0600 38.0200 37.9800
37.9800 37.9800 38.0000
38.0000 38.0000 38.0500
37.9500 38.0000 38.0200
38.0000 38.0600 37.9800
38.0600 38.0200 37.9800
38.0000 37.9800 37.9600
再生性计算为0，请教高人指点，多谢