我有一组数据, 想根据两个变量随机提取 (region & group), 每组提取3行 (如原始数据小于3行, 则全部提取)

比如, region = south   group=small 结果只有 3 行 (random sampling),
但是region = south   group=big 结果只有 2 行, 因为总共只用2行.

我现在用Excel VBA 做, 哪位指教一下, SAS怎么写? 先谢谢了

Name	region	group	feedback
A	south	small	4
B	south	small	5
C	south	small	3
D	south	small	7
E	south	big	6
F	south	big	8
G	North	big	5
H	North	big	9
I	North	big	4
J	North	big	6
K	North	small	7
L	North	small	7
M	North	small	9
N	North	small	9
O	West	big	5
P	West	big	2
Q	West	small	2
R	West	small	5