ggplot add customized sample

Question

I am using the following code (related part only) to generate my graph

p <- ggplot(avg.dice, aes(x=type, y=average)) +
    theme_bw() +
    geom_point() +
    geom_point(aes(x=type, y=cc.average), col="red", shape = 8) +
    geom_errorbar(aes(ymin=ci.lower, ymax=ci.upper))+
    theme(plot.margin=unit(c(2,2,2,3),"lines"))

How can I make a legend showing that the red star is for "test1" and the black solid dot is for "test2"? Both points are generated using geom_point with different color and shape.

My data points look like this:

median.dice
      type median ci.lower ci.upper cc.median
1      e70 0.6250    0.550    0.725     0.575
2      e89 0.5500    0.450    0.650     0.525
3      f10 0.6500    0.550    0.725     0.525
4      f15 0.4500    0.375    0.525     0.325
5      f20 0.6000    0.525    0.675     0.600
6      f22 0.4500    0.400    0.525     0.350
7      f48 0.3000    0.200    0.500     0.125
8      f80 0.6500    0.550    0.750     0.350
9     i3i8 0.5500    0.500    0.650     0.400
10      m5 0.6250    0.550    0.725     0.575
11 series6 0.5500    0.500    0.675     0.350
12 series7 0.5375    0.450    0.625     0.425
13      x3 0.6250    0.550    0.725     0.750
14   z4e85 0.5750    0.500    0.675     0.625

Answer 1

Using scale_shape_manual and scale_colour_manual while also specifying shape and colour within aes in the geom_point calls should work.

ggplot(median.dice, aes(x=type, y=median)) +
    theme_bw() +
    geom_point(aes(colour = 'test2', shape = 'test2')) +
    geom_point(aes(x = type, y = cc.median, colour = 'test1', shape = 'test1')) +
    geom_errorbar(aes(ymin=ci.lower, ymax=ci.upper))+
    theme(plot.margin=unit(c(2,2,2,3),"lines"))+
    scale_shape_manual(values = c('test1' = 8, 'test2' = 16), name = 'Test')+
    scale_colour_manual(values = c('test1' = 'red', 'test2' = 'black'), name = 'Test')

data

median.dice <- structure(list(type = c("e70", "e89", "f10", "f15", "f20", "f22", 
"f48", "f80", "i3i8", "m5", "series6", "series7", "x3", "z4e85"
), median = c(0.625, 0.55, 0.65, 0.45, 0.6, 0.45, 0.3, 0.65, 
0.55, 0.625, 0.55, 0.5375, 0.625, 0.575), ci.lower = c(0.55, 
0.45, 0.55, 0.375, 0.525, 0.4, 0.2, 0.55, 0.5, 0.55, 0.5, 0.45, 
0.55, 0.5), ci.upper = c(0.725, 0.65, 0.725, 0.525, 0.675, 0.525, 
0.5, 0.75, 0.65, 0.725, 0.675, 0.625, 0.725, 0.675), cc.median = c(0.575, 
0.525, 0.525, 0.325, 0.6, 0.35, 0.125, 0.35, 0.4, 0.575, 0.35, 
0.425, 0.75, 0.625)), .Names = c("type", "median", "ci.lower", 
"ci.upper", "cc.median"), class = "data.frame", row.names = c("1", 
"2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", 
"14"))