R . apply. tapply, table , .
Julien , (, ) , , . , "neuter", "neuter" , , . , .
, ( "" ), .
df<-as.data.frame(matrix(c("A-bom","de","A-bom","die","A-bom","de","A-bom","een","A-bom","n","A-bom","de","acroniem","het","acroniem","t","acroniem","het","acroniem","n","acroniem","een","act","de","act","het","act","die","act","dat","act","t","act","n"), byrow=T, ncol=2), stringsAsFactors=F)
names(df)<-c("node", "precedingWord")
classes<-c("t"="neuter", "het"="neuter" ,"dat"="neuter", "de"="non-neuter", "die"="non-neuter", "blorble"="nonword")
df$class<-"rest"
df$class<-ifelse(!is.na(classes[df$precedingWord]), classes[df$precedingWord], "rest")
table(df$node, df$class)
df$class<-factor(df$class)
levels(df$class)<-c(levels(df$class), unique(classes))
table(df$node, df$class)