小编Man*_*uel的帖子

我是R的新手,没有为我的问题找到解决方案.我真的希望你能帮助我.

虽然有更多的列和观察,但我的数据框如下所示:

dt <- data.frame(hid = c(1, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4),
                     syear = c(2000, 2001, 2003, 2003, 2003, 2000, 2000, 2001, 2001, 2002, 2002),
                     employlvl = c("Full-time", "Part-time", "Part-time", "Unemployed", "Unemployed",
                                    "Full-time", "Full-time", "Full-time", "Unemployed", "Part-time", 
                                    "Full-time"),
                     relhead = c("Head", "Head", "Head", "Partner", "other", "Head", 
                                                  "Partner", "Head", "Partner", "Head", "Partner")) 

| hid | syear |  employlvl  |       relhead         |
|-----|-------|-------------|-----------------------|
|  1  | 2000  |  Full-time  |         Head          |
|  2  | 2001  | …