r - 计算 R 数据框架中成员的频率

Question

我有以下 data.frame:

authors <- data.frame(
    surname = I(c("Tukey", "Venables", "Tierney", "Ripley", "McNeil")),
    nationality = c("US", "Australia", "US", "UK", "Australia"),
    deceased = c("yes", rep("no", 3),"noinfo"))

产生这个输出:

      surname nationality deceased
1    Tukey          US      yes
2 Venables   Australia       no
3  Tierney          US       no
4   Ripley          UK       no
5   McNeil   Australia   noinfo

我想要做的是获取 deceased的频率来自 nationality .
产生这个输出:

US yes 1
US no  1
US noinfo 0
Australia yes 0
Australia no 1
Australia noinfo 1
UK yes 0
UK no 1
UK noinfo 0

目前我只能通过 tables显示统计信息.

stat <- table(authors)

我不确定如何通过访问表的元素来继续。
建议将不胜感激。

Answer 1

您需要table关于您想要发生的事情...

table( authors[ c("nationality" , "deceased" ) ] )
#           deceased
#nationality no noinfo yes
#  Australia  1      1   0
#  UK         1      0   0
#  US         1      0   1

并获得您想要的确切输出...将其转换为 data.frame ....

data.frame( table( authors[ c("nationality" , "deceased" ) ] ) )
#  nationality deceased Freq
#1   Australia       no    1
#2          UK       no    1
#3          US       no    1
#4   Australia   noinfo    1
#5          UK   noinfo    0
#6          US   noinfo    0
#7   Australia      yes    0
#8          UK      yes    0
#9          US      yes    1