Ich erstelle ein Diagramm in ggplot aus einem 2 x 2-Studiendesign und möchte 2 Farben und 2 Symbole verwenden, um meine 4 verschiedenen Behandlungskombinationen zu klassifizieren. Derzeit habe ich 2 Legenden, eine für die Farben und eine für die beiden Formen. Wie kann ich sie zu einer einzigen Legende zusammenfassen, sodass ich einen blauen Kreis, einen roten Kreis, ein blaues Dreieck und ein gelesenes Dreieck habe?

Daten:

state1 <- c(rep(c(rep("N", 7), rep("Y", 7)), 2))
year <- rep(c(2003:2009), 4)
group1 <- c(rep("C", 14), rep("E", 14))
group2 <- paste(state1, group1, sep = "")
beta <- c(0.16,0.15,0.08,0.08,0.18,0.48,0.14,0.19,0.00,0.00,0.04,0.08,0.27,0.03,0.11,0.12,0.09,0.09,0.10,0.19,0.16,0.00,0.11,0.07,0.08,0.09,0.19,0.10)
    lcl <- c(0.13,0.12,0.05,0.05,0.12,0.35,0.06,0.13,0.00,0.00,0.01,0.04,0.20,0.00,0.09,0.09,0.06,0.06,0.07,0.15,0.11,0.00,0.07,0.03,0.05,0.06,0.15,0.06)
    ucl <- c(0.20,0.20,0.13,0.14,0.27,0.61,0.28,0.27,0.00,1.00,0.16,0.16,0.36,0.82,0.14,0.15,0.13,0.13,0.15,0.23,0.21,0.00,0.15,0.14,0.12,0.12,0.23,0.16)
data <- data.frame(state1,year,group1,group2,beta,lcl,ucl)

Handlung:

library(ggplot2)
pd <- position_dodge(.65)
ggplot(data = data, aes(x = year, y = beta, colour = state1, group = group2, shape = group1)) +
  geom_point(position = pd, size = 4) +
  geom_errorbar(aes(ymin = lcl, ymax = ucl),colour = "black", width = 0.5, position = pd) +
  scale_colour_hue(name = "Treatment & State",  #Legend label, use darker colors
                   labels = c("Control", "Exclosure"),
                   l = 40) +
  scale_shape(name = "State", labels = c("Non-F", "Flwr"))