Setup

library(tidyverse)

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A Saturated Scatterplot

I’ll use the diamonds dataset to demonstrate the problem and the solutions.

First the Problem

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point()

Very little detail is visible. With 53,940 rows, the scatterplot is totally saturated.

Solution

Use the transparency (alpha) and/or size parameters.

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(alpha = .1)

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(alpha = .01)

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(alpha = .005)

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(size = .1)

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(size = .001)

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(alpha = .1,size=.1)

Smoothing

You can use a smoother instead of a scatterplot.

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_smooth()

## `geom_smooth()` using method = 'gam' and formula = 'y ~ s(x, bs = "cs")'

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_point(alpha=.01) +
  geom_smooth(aes(color = cut))

## `geom_smooth()` using method = 'gam' and formula = 'y ~ s(x, bs = "cs")'

Density Plot

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_density_2d()

diamonds %>% 
  ggplot(aes(x = carat, y = price)) +
  geom_density_2d_filled()