Plotting categorical data along with numerical variable

Question

I have data like as shown below

I would like to represent the above tabular data in a visual form.

However, the below graph may not work because my real data as 50K unique drug names. Doing so, will make the x-axis messy. Is there any other condensed way to represent this?

So, is there any better way to represent this? Can you share some suggestions on how this can be represented?

Answer 1

What would you like to communicate with the plot?

For a summary of the dataset, you can think about a scatter plot with x = unique no patients, y = no of units prescribed and put a label close to each point representing the drug id.
This is an example with the dataset mtcars

library("ggplot2")
data("mtcars")

mtcars$mdl <- rownames(mtcars)
ggplot(mtcars, aes(x=mpg, y=wt, label=mdl)) +
  geom_point() +
  geom_text(check_overlap=TRUE, vjust="inward", hjust="inward")

Set check_overlap=FALSE if you want to see all (overlapping) labels.

Since you have a large number of points, you may want to label just those that can be informative about how the data is distributed. To do that, you can do a scatter plot

plot(x=mtcars$mpg, y=mtcars$wt)

then use identify to click on the points you want to label

identify(x=mtcars$mpg, y=mtcars$wt, labels=mtcars$mdl, cex=0.8)

You have to click on the points that you want to label, then press ESC.

If you want to do it programmatically, you can set all labels to NA except those that you want to show:

mtcars$mdl_1 <- mtcars$mdl
mtcars$mdl_1[-sample(nrow(mtcars), 5)] <- NA  # Select 5 random to keep

ggplot(mtcars, aes(x=mpg, y=wt, label=mdl_1)) +
  geom_point() +
  geom_text(check_overlap=FALSE,vjust="inward",hjust="inward")

More than 2 variables:

In this case, you can use pairs or ggpairs from GGally package

library(GGally)

mtcars$mdl <- rownames(mtcars)
mtcars$mdl_1 <- mtcars$mdl
mtcars$mdl_1[-sample(nrow(mtcars), 5)] <- NA  ## Showing 5 random labels

gg <- ggpairs(data=mtcars, columns=c(1:5), aes(label=mdl_1))
for (i in 1:25) {  ## 5*5 plots
  for (j in 1:25) {
    if (j < i) {  ## lower half
      plt <- getPlot(gg,i,j) + geom_text(size=3) + geom_point(size=1)
      gg <- putPlot(gg,plt,i,j)
    }
  }
}

gg

where I've customized the scatter plots using the method described here.