Stacked barplot using ggplot2 - data visualisation

1
votes

I have very little experience with R and am trying to make a stacked barplot using ggplot2. I have 2 groups - control and experimental, and 2 choices - red and green. I'm not sure how to organise my data.

There were 80 animals in my trial (control n=40, experimental n=40) and they were given the choice of red and green substrate, I noted which substrate they chose, and that's the data I'm trying to plot.

I would essentially want 'Experimental' and 'Control on the x-axis, and the number of choices on the y-axis (e.g. Control, Red n=20, Control, Green = 12 etc).

Any help would be appreciated!

Edited to add:

This is the graph it's outputting

This is the code I'm using (including suggested adjustments):

df <- data.frame(group = rep(c("control", "experimental"), each = 40),
                 substrate = sample (c("red","green"), 80, TRUE))

ggplot(df, aes(x = group, y = substrate, fill = substrate)) + 
  geom_bar(stat = "identity") +
  scale_fill_manual(values = c("red", "green"))

This is the output:

structure(list(group = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L,1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), .Label = c("control", "experimental"
), class = "factor"), substrate = structure(c(1L, 2L, 1L, 2L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 1L, 1L, 2L, 1L, 1L, 1L, 
2L, 2L, 2L, 1L, 1L, 2L, 2L, 1L, 1L, 1L, 2L, 2L, 1L, 2L, 1L, 1L, 
2L, 1L, 1L, 2L, 1L, 2L, 1L, 2L, 1L, 2L, 2L, 2L, 1L, 2L, 1L, 1L, 
1L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 1L, 
1L, 1L, 2L, 2L, 1L, 1L, 1L, 2L, 2L, 2L, 1L, 2L), .Label = c("green", 
"red"), class = "factor")), class = "data.frame", row.names = c(NA, 
-80L))

output from df(behaviour) - original dataframe

structure(list(group = structure(c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("Control", "Experimental"
), class = "factor"), substrate = structure(c(1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("Green", 
"Red"), class = "factor")), class = "data.frame", row.names = c(NA, 
-80L))
2
rggplot2
Hi ChristyJudd, so you have tabulated your data. @AllanCameron's code assumes you haven't done that. you need to do y = <column containing counts> and geom_bar(stat="identity") - StupidWolf
The best is if you show us how your data frame looks like :) say df is your dataframe , do dput(df) and paste the output as part of your post? - StupidWolf
Thanks for your help. When I do dput(df) it comes up with something strange, but when I open 'df' from my global environment it shows my data? I can still paste above if you'd like. When I use the code you suggest the y-axis labels are 'red' and 'green' rather than a count of the number of red and green, which is the issue I was facing before. I can try and paste the graph above with the code I used if that would help at all? - Christy Judd
It's ok, dput(df) gives something like structure(....) right? Paste that output (starting from structure...) as part of your post. Screen shots are not going to help much unfortunately.. - StupidWolf
I'll paste that output now. - Christy Judd

2 Answers

0
votes

Your data:

behaviour=structure(list(group = structure(c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("Control", "Experimental"
), class = "factor"), substrate = structure(c(1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("Green", 
"Red"), class = "factor")), class = "data.frame", row.names = c(NA, 
-80L))

We can tabulate your data:

 table(behaviour$group,behaviour$substrate)                           
               Green Red
  Control         10  30
  Experimental    27  13

So you can only specify fill or y with geom_bar. In your case, you specify the fill, the geom_bar() function will do the counting for you:

ggplot(behaviour,aes(x=group,fill=substrate))+
geom_bar() + scale_fill_manual(values=c("#29c7ac","#c02739"))

enter image description here

0
votes

You could have your data like this, with one row for each observation (i.e. each animal), with the group and the substrate recorded for each:

df <- data.frame(group = rep(c("control", "experimental"), each = 40),
                 substrate = rep(c("green", "red", "green", "red"), c(10, 30, 27, 13)))

Now define your plot using ggplot, specifying group as your x axis, and ..count.. as your y axis. Use geom_bar to get the stacked bars you are looking for, and finally use scale_fill_manual to set the colours:

library(ggplot2)

ggplot(df, aes(x = group, y = ..count.., fill = substrate)) + 
  geom_bar(colour = "black") +
  scale_fill_manual(values = c("green", "red"))

enter image description here