谢谢哈,这样的做法是可以求出各个细格的统计量,但是
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-> a = 男, b = 1
variable | mean sd N
-------------+------------------------------
y | 25.5 4.795832 4
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-> a = 男, b = 2
variable | mean sd N
-------------+------------------------------
y | 10.75 2.872281 4
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有没有可以合在一起方法呢?