How to create a stacked bar chart from summarized data in ggplot2

Question

I\'m trying to create a stacked bar graph using ggplot 2. My data in its wide form, looks like this. The numbers in each cell are the frequency of responses.

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Answer 1

You haven't said what it is that's not right about your solution. But some issues that could be construed as problems, and one possible solution for each, are:

• The x axis tick mark labels run into each other. SOLUTION - rotate the tick mark labels;
• The order in which the labels (and their corresponding bars) appear are not the same as the order in the original dataframe. SOLUTION - reorder the levels of the factor 'activity';
• To position text inside the bars set the vjust parameter in position_stack to 0.5

The following might be a start.

    # Load required packages
library(ggplot2)
library(reshape2)

    # Read in data
df = read.table(text = "
activity                         yes    no  dontknow
Social.events                     27    3   3
Academic.skills.workshops         23    5   8
Summer.research                   22    7   7
Research.fellowship               20    6   9
Travel.grants                     18    8   7
Resume.preparation                17    4   12
RAs                               14    11  8
Faculty.preparation               13    8   11
Job.interview.skills              11    9   12
Preparation.of.manuscripts        10    8   14
Courses.in.other.campuses          5    11  15
Teaching.fellowships               4    14  16
TAs                                3    15  15
Access.to.labs.in.other.campuses   3    11  18
Interdisciplinay.research          2    11  18
Interdepartamental.projects        1    12  19", header = TRUE, sep = "")

    # Melt the data frame
dfm = melt(df, id.vars=c("activity"), measure.vars=c("yes","no","dontknow"),
    variable.name="haveused", value.name="responses")

    # Reorder the levels of activity
dfm$activity = factor(dfm$activity, levels = df$activity)

    # Draw the plot
ggplot(dfm, aes(x = activity, y = responses, group = haveused)) + 
geom_col(aes(fill=haveused)) +
theme(axis.text.x = element_text(angle = 90, hjust = 1, vjust = 0.25)) +
geom_text(aes(label = responses), position = position_stack(vjust = .5), size = 3)  # labels inside the bar segments