r - 如何将数据框中的向量值与 R 中的常量进行比较？

Question

背景:我正在使用一些人口普查公众使用的微数据样本(特别是美国社区调查)来检查已完成不同学位(例如高中文凭、学士学位、硕士学位)的人的行为。该公共(public)使用文件的变量称为“Schooling”。问题是变量“Schooling”中包含的代码每年都在变化。例如，对于截至 2007 年的文件，“13”值反射(reflect)完成学士学位，但从 2008 年开始，当某人完成学士学位时，该值变为“21”。
目标:创建一个新的“Degree Competed”变量，翻译“Schooling”代码以反射(reflect)完成的学位级别，同时考虑到文件的年份。
后勤:所有年份的文件都已连接起来，出于审查目的，我必须按原样处理文件，而不是在它到达这一点之前对其进行更正。
现有代码:这是我尝试过的。

if      (original.file$year %in% c(2000,2001)) {
    if      (original.file$Schooling <= 08) {original.file$degree.completed <- 0}
    else if (original.file$Schooling <= 10) {original.file$degree.completed <- 1}
    else if (original.file$Schooling <= 12) {original.file$degree.completed <- 2}
    else if (original.file$Schooling == 13) {original.file$degree.completed <- 3}
    else if (original.file$Schooling == 14) {original.file$degree.completed <- 4}
    else if (original.file$Schooling == 15) {original.file$degree.completed <- 5}
    else if (original.file$Schooling == 16) {original.file$degree.completed <- 6}
    }
else if (original.file$year %in% c(2002,2003,2004,2005,2006,2007)) {
    if      (original.file$Schooling <= 08) {original.file$degree.completed <- 0}
    else if (original.file$Schooling <= 11) {original.file$degree.completed <- 1}
    else if (original.file$Schooling == 12) {original.file$degree.completed <- 2}
    else if (original.file$Schooling == 13) {original.file$degree.completed <- 3}
    else if (original.file$Schooling == 14) {original.file$degree.completed <- 4}
    else if (original.file$Schooling == 15) {original.file$degree.completed <- 5}
    else if (original.file$Schooling == 16) {original.file$degree.completed <- 6}
    }
else if (original.file$year %in% c(2008,2009,2010,2011)) {
    if      (original.file$Schooling <= 15) {original.file$degree.completed <- 0}
    else if (original.file$Schooling <= 19) {original.file$degree.completed <- 1}
    else if (original.file$Schooling == 20) {original.file$degree.completed <- 2}
    else if (original.file$Schooling == 21) {original.file$degree.completed <- 3}
    else if (original.file$Schooling == 22) {original.file$degree.completed <- 4}
    else if (original.file$Schooling == 23) {original.file$degree.completed <- 5}
    else if (original.file$Schooling == 24) {original.file$degree.completed <- 6}
    }

问题:我收到以下此类警告消息。

Warning messages:

1: In if (original.file$year %in% c(2000, 2001)) { : the condition has length > 1 and only the first element will be used

2: In if (original.file$Schooling <= 8) { : the condition has length > 1 and only the first element will be used

3: In if (original.file$Schooling <= 10) { : the condition has length > 1 and only the first element will be used

问题:我知道这里的“if”存在向量与标量问题，正如我从 StackOverflow 上的其他问题中看到的那样，但答案似乎不适用于这种情况。这里的解决方案是什么？

Answer 1

首先，使用 cut或 table而不是所有这些if的和 else的:

CutOffs1 <- c(0,8,10,12,13,14,15,16)
CutOffs2 <- c(0,8,11,12,13,14,15,16)
CutOffs3 <- c(0,15,19,20,21,22,23,24)
CutOffs <- cbind(CutOffs1, CutOffs2, CutOffs3)
MyTable <- apply(CutOffs, 2, function(X) cut(1:24, X, FALSE)-1)

      CutOffs1 CutOffs2 CutOffs3
 [1,]        0        0        0
 [2,]        0        0        0
 [3,]        0        0        0
 [4,]        0        0        0
 [5,]        0        0        0
 [6,]        0        0        0
 [7,]        0        0        0
 [8,]        0        0        0
 [9,]        1        1        0
[10,]        1        1        0
[11,]        2        1        0
[12,]        2        2        0
[13,]        3        3        0
[14,]        4        4        0
[15,]        5        5        0
[16,]        6        6        1
[17,]       NA       NA        1
[18,]       NA       NA        1
[19,]       NA       NA        1
[20,]       NA       NA        2
[21,]       NA       NA        3
[22,]       NA       NA        4
[23,]       NA       NA        5
[24,]       NA       NA        6

您还需要 cut年成因素。

original.file$Period <- cut(original.file$year, c(2000,2001, 2007, 2011), FALSE,   
                            include.lowest=TRUE) 
## To demonstrate:
    > cbind(2000:2011, cut(2000:2011, c(2000,2001, 2007, 2011), FALSE,   
+     include.lowest=TRUE))
      [,1] [,2]
 [1,] 2000    1
 [2,] 2001    1
 [3,] 2002    2
 [4,] 2003    2
 [5,] 2004    2
 [6,] 2005    2
 [7,] 2006    2
 [8,] 2007    2
 [9,] 2008    3
[10,] 2009    3
[11,] 2010    3
[12,] 2011    3

然后你应该能够做到:

Degrees <- apply(original.file, 1, function(X) MyTable[X['Schooling'], X['Period']])