ggplot2; how to draw group mean lines of two different groups in a categorical variable

Question

I have a following set of data;

    V1 V2  V3
 1: G1 P1 82.7
 2: G2 P1 64.6
 3: G2 P1 81.2
 4: G2 P1 95.3
 5: G1 P1 80.0
 6: G2 P1   NA
 7: G2 P1 65.0
 8: G1 P1 83.8
 9: G1 P1 88.0
10: G1 P1 66.9
11: G1 P1 56.8
12: G1 P2 65.1
13: G2 P2 57.7
14: G2 P2 60.4
15: G2 P2 18.6
16: G1 P2 41.2
17: G2 P2 47.0
18: G2 P2 37.1
19: G1 P2 18.8
20: G1 P2 47.9
21: G1 P2 40.0
22: G1 P2 54.3

I made the following plot by using ggplot2;

ggplot(a,aes(x=V2,y=V3))+
    geom_jitter(aes(group=V1,color=V1,na.rm=T), position =position_jitterdodge())+
    stat_summary(fun.y="mean",geom="crossbar", 
             mapping=aes(ymin=..y.., ymax=..y..), width=1)

V1 contains two categorial variable, P1 and P2 and within them, there are two subcategories, G1 and G2. What I like to do is to generate the plot with mean lines of G1 and G2 but the code above gives me the mean of categorical variables, P1 and P2.

I'd really appreciate any help on this.

Thanks.

Answer 1

Move color=V1 to aes() of ggplot() to have different colors for crossbars and aldo add postion_dodge() to stat_summary() .

ggplot(a,aes(x=V2,y=V3,color=V1))+
  geom_jitter(aes(group=V1,na.rm=T), position =position_jitterdodge())+
  stat_summary(fun.y="mean",geom="crossbar", 
               mapping=aes(ymin=..y.., ymax=..y..), width=1,
               position=position_dodge(),show.legend = FALSE)