问题
StudentData <- data.frame(gender = sample( c("male","female"), 100, replace=TRUE),
degree = sample( c("Associates", "Masters", "PhD"), 100, replace=TRUE),
category = sample( c("Audit", "Credit"), 100, replace=TRUE))
In the following dataset, I am trying to create a bar graph that plots the percentage of the sample which have an Associate's, Master's, or PhD, separated by gender (done by using facet_grid() ). This is what I have generated so far:
StudentData %>% ggplot(., aes(x=degree, group=gender)) +
geom_bar(aes(y=..prop..), stat="count", position=position_dodge()) +
geom_text(aes(label=scales::percent(round(..prop..,2)),
y=..prop..), stat="count", vjust=-.5) +
scale_y_continuous(limits=c(0,1),labels = scales::percent) +
ylab("Percent of Sample") +
facet_grid(~gender)
However, I would also like to display the difference between the groups "Audit" and "Credit" on each graph as side by bars. Yet, when I add "fill=category" to the aesthetics of ggplot, nothing changes:
StudentData %>% ggplot(., aes(x=degree, group=gender, fill=category)) +
geom_bar(aes(y=..prop..), stat="count", position=position_dodge()) +
geom_text(aes(label=scales::percent(round(..prop..,2)),
y=..prop..), stat="count", vjust=-.5) +
scale_y_continuous(limits=c(0,1),labels = scales::percent) +
ylab("Percent of Sample") +
facet_grid(~gender)
I realize that usually this is accomplished using geom_bar(stat="identity", position=position_dodge())
but when I change stat="identity"
, the following error message appears:
Error in FUN(X[[i]], ...) : object 'prop' not found
Any idea how to have a facet graph, use special characters such as ..prop.. AND add another fill to a ggplot2 graph?
回答1:
You could create the necessary four group
s (instead of two) like this:
StudentData %>%
ggplot(., aes(x=degree, group=interaction(gender, category), fill=category)) +
geom_bar(aes(y=..prop..), stat="count", position=position_dodge()) +
geom_text(aes(label=scales::percent(round(..prop..,2)),
y=..prop..), stat="count", vjust=-.5, position=position_dodge(.9)) +
scale_y_continuous(limits=c(0,1),labels = scales::percent) +
ylab("Percent of Sample") +
facet_grid(~gender)
来源:https://stackoverflow.com/questions/48086575/ggplot2-problems-with-using-prop-and-grouping-bar-graph-by-another-categor