How do I manually change the key labels in a legend in ggplot2?

The standard way is to use the scale functions to change the displayed labels for groups. You can replace your ggplot call with.

The standard way is to use the scale functions to change the displayed labels for groups. You can replace your ggplot call with ggplot(data, aes(grp, fill=outcome)) + geom_bar() +xlab("group") + ylab("number of subjects") + scale_fill_discrete("Serologic response", breaks=c("(10.1,79.9","(79.9,150"), labels=c("double negative", "positive for a and/or b")) Note that the scale's title has been incorporated into the scale_fill_discrete call. You can do this with the axes too, if you like ggplot(data, aes(grp, fill=outcome)) + geom_bar() + scale_x_discrete("group") + scale_y_continuous("number of subjects") + scale_fill_discrete("Serologic response", breaks=c("(10.1,79.9","(79.9,150"), labels=c("double negative", "positive for a and/or b")).

I found a hybrid way of doing it. It does relabel the factor but I do not have to do it in the dataframe. Instead I just do it in the ggplot command.

Ggplot(data, aes(grp, fill=factor(outcome,labels=c("low","high")))) + geom_bar() +xlab("group") +ylab("number of subjects") + labs(fill="Serologic response") Are there any other ways?

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.