plot multiple groupwise means in R

Question

my data looks like the following. I need to create some lineplot/barplot for average val for each group like, status and category in the csv file.
Data in dput format.

df <-
structure(list(val = c(4608, 4137, 6507, 5124, 
3608, 34377, 5507, 5624, 4608, 4137, 6507, 5124, 
3608, 3437, 5507, 5507, 5624), status = c("1x", 
"1x", "1x", "2x", "2x", "2x", "2x", "2x", "50xy", 
"50xy", "50xy", "60xy", "60xy", "70xy", "xyz", 
"xyz", "xyz"), category = c("A", "C", "A", "A", 
"A", "B", "B", "C", "B", "C", "A", "B", "C", 
"B", "B", "C", "C")), row.names = c(NA, 
-17L), class = "data.frame")

I tried the following code but could not figure out the whole thing.

library(ggplot2)
ggplot(df, aes(x = status, y = val, group = category, color = source)) + 
      geom_smooth(method = "loess")

Help to plot them (each group wise, such as plotting mean val for each 2x and B) in a single window would be really appreciated. Thank you.

Uwe · Accepted Answer · 2019-01-02 12:53:35Z

2

You can do:

library(dplyr)
library(ggplot2)
df %>%
    group_by(category, status) %>%
    mutate(agg = mean(val)) %>%
    ggplot(., aes(status, agg, fill = category, color=status))+
    geom_col(position = "dodge")

edited Jan 2, 2019 at 12:53

Uwe

42.8k13 gold badges97 silver badges143 bronze badges

answered Dec 20, 2018 at 19:41

YOLO

22k5 gold badges25 silver badges42 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

camille Over a year ago

The OP wants to plot the means of groups, not just the values. Also just as shorthand, geom_col() is equivalent to geom_bar(stat = "identity")

Rui Barradas Over a year ago

The bars have uneven widths, the last solution in this answer solved it for me.

temp Over a year ago

thank you @YOLO, for the hint, it worked, later I converted into line plots.

Uwe · Accepted Answer · 2019-01-02 14:48:49Z

This question already has an accepted answer which requires to compute the aggregated mean(val) by status, category group beforehand.

However, ggplot2 includes transformations (or stats) which enable us to create the desired plot in one go without utilizing other packages:

library(ggplot2)
ggplot(df, aes(x = status, y = val, group = category, colour = category)) +
  stat_summary(geom = "line", fun.y = "mean")

This creates a line plot of the mean values as requested by the OP:

Alternatively, we can tell geom_line to use a summary statistics:

ggplot(df, aes(status, val, group = category, colour = category)) +
  geom_line(stat = "summary", fun.y = "mean")

which creates the same plot.

stat_summary() can also be used to show the original data and the summary statistics combined in one plot:

ggplot(df, aes(status, val, group = category, colour = category)) +
  geom_point() +
  stat_summary(geom = "line", fun.y = "mean")

This can help to better understand the structure of the underlying data, e.g., outliers. Please, note the different y scale.

Collectives™ on Stack Overflow

plot multiple groupwise means in R

2 Answers 2

3 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related