如何使用 R 或 Stata 识别数据集中成绩保留的学生？

Question

我有一个小数据集，其中有 4 条关于学生学业进展的数据记录。 第一列是id，第二列是等级。我的目标是创建一个名为“GR”（成绩保留）的新变量来识别成绩保留的学生。如果是，则GR=1，否则GR=0。生成的数据集应如下所示，

structure(list(id = c(1000, 1000, 1000, 1000, 1000, 1000, 1001, 
1001, 1001, 1001, 1001, 1001, 1001, 1002, 1002, 1002, 1002, 1002, 
1002, 1002, 1002, 1002, 1003, 1003, 1003, 1003, 1003, 1003), 
    grade = c("1", "2", "3", "4", "5", "6", "1", "2", "3", "4", 
    "5", "5", "6", "1", "2", "2", "3", "4", "4", "4", "5", "6", 
    "1", "2", "3", "4", "5", "6"), GR= c("0", "0", 
    "0", "0", "0", "0", "1", "1", "1", "1", "1", "1", "1", "1", 
    "1", "1", "1", "1", "1", "1", "1", "1", "0", "0", "0", "0", 
    "0", "0")), class = c("tbl_df", "tbl", "data.frame"), row.names = c(NA, 
-28L))->df_new

原始数据集的结构如下，

structure(list(id = c(1000, 1000, 1000, 1000, 1000, 1000, 1001, 
1001, 1001, 1001, 1001, 1001, 1001, 1002, 1002, 1002, 1002, 1002, 
1002, 1002, 1002, 1002, 1003, 1003, 1003, 1003, 1003, 1003), 
    grade = c("1", "2", "3", "4", "5", "6", "1", "2", "3", "4", 
    "5", "5", "6", "1", "2", "2", "3", "4", "4", "4", "5", "6", 
    "1", "2", "3", "4", "5", "6")), row.names = c(NA, -28L), class = c("tbl_df", 
"tbl", "data.frame"))->df

感谢您的帮助或指导！

Answer 1

您可以检查每个组是否包含任何 重复 等级：

library(tidyverse)

df %>%
  group_by(id) %>%
  mutate(GR = +any(duplicated(grade)))

输出

      id grade    GR
   <dbl> <chr> <int>
 1  1000 1         0
 2  1000 2         0
 3  1000 3         0
 4  1000 4         0
 5  1000 5         0
 6  1000 6         0
 7  1001 1         1
 8  1001 2         1
 9  1001 3         1
10  1001 4         1
# … with 18 more rows

Answer 2

如果您也想要 Stata 解决方案，那么这个问题就不会以友好的方式提出，但这是一种方法。这个想法只是获取任何重复成绩的指示符，然后将其传播到该标识符的其他观察（记录、行）。

* Example generated by -dataex-. For more info, type help dataex
clear
input int id byte grade float GR
1000 1 0
1000 2 0
1000 3 0
1000 4 0
1000 5 0
1000 6 0
1001 1 1
1001 2 1
1001 3 1
1001 4 1
1001 5 1
1001 5 1
1001 6 1
1002 1 1
1002 2 1
1002 2 1
1002 3 1
1002 4 1
1002 4 1
1002 4 1
1002 5 1
1002 6 1
1003 1 0
1003 2 0
1003 3 0
1003 4 0
1003 5 0
1003 6 0
end

bysort id grade : gen wanted = _N > 1

bysort id (wanted) : replace wanted = wanted[_N]

sort id grade

list, sepby(id)

     +----------------------------+
     |   id   grade   GR   wanted |
     |----------------------------|
  1. | 1000       1    0        0 |
  2. | 1000       2    0        0 |
  3. | 1000       3    0        0 |
  4. | 1000       4    0        0 |
  5. | 1000       5    0        0 |
  6. | 1000       6    0        0 |
     |----------------------------|
  7. | 1001       1    1        1 |
  8. | 1001       2    1        1 |
  9. | 1001       3    1        1 |
 10. | 1001       4    1        1 |
 11. | 1001       5    1        1 |
 12. | 1001       5    1        1 |
 13. | 1001       6    1        1 |
     |----------------------------|
 14. | 1002       1    1        1 |
 15. | 1002       2    1        1 |
 16. | 1002       2    1        1 |
 17. | 1002       3    1        1 |
 18. | 1002       4    1        1 |
 19. | 1002       4    1        1 |
 20. | 1002       4    1        1 |
 21. | 1002       5    1        1 |
 22. | 1002       6    1        1 |
     |----------------------------|
 23. | 1003       1    0        0 |
 24. | 1003       2    0        0 |
 25. | 1003       3    0        0 |
 26. | 1003       4    0        0 |
 27. | 1003       5    0        0 |
 28. | 1003       6    0        0 |
     +----------------------------+