Introduction

Introduction to Data Visualization with ggplot2

Rick Scavetta

Founder, Scavetta Academy

Your instructor - Rick Scavetta

- e-mail: [email protected]

- Twitter: @Rick_Scavetta

Data visualization & data science

A core skill in Data Science.

Exploratory versus explanatory

MASS::mammals

MASS::mammals

                              body   brain
Arctic fox                   3.385   44.50
Owl monkey                   0.480   15.50
Mountain beaver              1.350    8.10
Cow                        465.000  423.00
Grey wolf                   36.330  119.50
Goat                        27.660  115.00
Roe deer                    14.830   98.20
...
Pig                        192.000  180.00
Echidna                      3.000   25.00
Brazilian tapir            160.000  169.00
Tenrec                       0.900    2.60
Phalanger                    1.620   11.40
Tree shrew                   0.104    2.50
Red fox                      4.235   50.40

A scatter plot

ggplot(mammals, aes(x = body, y = brain)) +
  geom_point()

1.1.1-1.png

Explore with a linear model

ggplot(mammals, aes(x = body, y = brain)) +
  geom_point(alpha = 0.6) +
  stat_smooth(
    method = "lm", 
    color = "red", 
    se = FALSE
  )

1.1.1-2.png

Explore: fine-tuning

ggplot(mammals, aes(x = body, y = brain)) +
  geom_point(alpha = 0.6) +
  coord_fixed() +
  scale_x_log10() +
  scale_y_log10() +
  stat_smooth(
    method = "lm", 
    color = "#C42126", 
    se = FALSE, 
    size = 1
  )

1.1.1-3.png

Publication-ready plot

1.1.1-4.png

Anscombe's plots

Let's practice!

Introduction to Data Visualization with ggplot2