R -模糊查找和重新编码

Question

我正在清理10多个学区提交的人口统计数据，这些数据没有标准化/统一。我想找到模式并重新编码它们，使数据干净简单。

假设我有一个变量叫做Race，其中一个类别是Native Hawaiian - Pacific Islander。

学校A将此类别作为Native Hawaiian or Other Pacific Islander提交。学校B将此类别提交为Native Hawaiian/Pacific Islander。学校C提交此类别为Native Hawaiian or Pacific Islander。

如果R在变量中看到Pacific这个词，它将重新编码为Native Hawaiian - Pacific Islander，我该如何重新编码?

原始数据:

df_original <- data.frame(Race=c("Native Hawaiian or Other Pacific Islander",
"Native Hawaiian/Pacific Islander", "Native Hawaiian or Pacific Islander",
"Black or African American", "Black", "Black/African American"))

这是理想的清理数据:

df_desired <- data.frame(Race=c("Native Hawaiian - Pacific Islander","Native Hawaiian - Pacific Islander",
"Native Hawaiian - Pacific Islander","Black - African American",
"Black - African American","Black - African American"))

Answer 1

对于包含"Pacific"的字符串，grepl()将返回TRUE否则为False。使用它来子集你的向量，并替换为你想要的字符串:

df_original$Race[grepl("Pacific", df_original$Race)] <- "Native Hawaiian - Pacific Islander"

Answer 2

使用str_detect和case_when

library(dplyr)
library(stringr)
df_original %>% 
mutate(Race2 = case_when(str_detect(Race, '\bPacific\b') ~
"Native Hawaiian - Pacific Islander", 
TRUE ~ "Black - African American"))

与产出

Race                              Race2
1 Native Hawaiian or Other Pacific Islander Native Hawaiian - Pacific Islander
2          Native Hawaiian/Pacific Islander Native Hawaiian - Pacific Islander
3       Native Hawaiian or Pacific Islander Native Hawaiian - Pacific Islander
4                 Black or African American           Black - African American
5                                     Black           Black - African American
6                    Black/African American           Black - African American

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另一种选择是创建一个键/值数据集，其中包含要替换的模式及其对应的值，然后用原始数据

执行regex_left_join(从fuzzyjoin)

library(fuzzyjoin)
keydat <- tibble(Race = c("Pacific", "Black"), 
Race2 = c("Native Hawaiian - Pacific Islander", "Black - African American"))
regex_left_join(df_original, keydat) %>%
transmute(Race = Race2)
#Joining by: "Race"
#                                Race
#1 Native Hawaiian - Pacific Islander
#2 Native Hawaiian - Pacific Islander
#3 Native Hawaiian - Pacific Islander
#4           Black - African American
#5           Black - African American
#6           Black - African American