change color for two geom_point() in ggplot2

Question

Sample dataset:

library(ggplot2)    
df = read.table(text = 
              \"id      year    value1  value2 value3
            1           2000    1   2000           


        

Answer 1

Is this what you are looking for?

ggplot(df, aes(y=id)) +
  geom_point(aes(x=year, color=value1), size=4) +
  geom_point(aes(x=value3, colour ='value3'), size=3) +
  geom_point(aes(x=value2, colour ='value2'), size=5) +
  scale_colour_manual(name="",  
                      values = c("1"="yellow", "2"="orange", "3"="red",
                                 "value3"="grey", "value2"="black"))

Basically, just putting all possible colour labels in a single list.