求问怎么把4个变量变成一个变量-经管之家官网！

例如，有4个产品ABCD，目前数据库里选A的人是1，没选的是0；选B的是1，没选的0.. C和D也是这样。选ABCD的人是不重合的，即单选，且选A的人＋选B的人+选C的人+选D的人等于样本总人数。我现在想合成一个多分类无序变量，其中选A的=1，选B的=3，C=2，D=4。请问使用什么方法才可以实现呢？
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