Challenge 5

Introduction to Visualization

Code

library(tidyverse)
library(ggplot2)
library(here)

knitr::opts_chunk$set(echo = TRUE, warning=FALSE, message=FALSE)

Read in data

Code

cereal <- here("posts","_data","cereal.csv")%>%
  read_csv()
cereal

# A tibble: 20 × 4
   Cereal                Sodium Sugar Type 
   <chr>                  <dbl> <dbl> <chr>
 1 Frosted Mini Wheats        0    11 A    
 2 Raisin Bran              340    18 A    
 3 All Bran                  70     5 A    
 4 Apple Jacks              140    14 C    
 5 Captain Crunch           200    12 C    
 6 Cheerios                 180     1 C    
 7 Cinnamon Toast Crunch    210    10 C    
 8 Crackling Oat Bran       150    16 A    
 9 Fiber One                100     0 A    
10 Frosted Flakes           130    12 C    
11 Froot Loops              140    14 C    
12 Honey Bunches of Oats    180     7 A    
13 Honey Nut Cheerios       190     9 C    
14 Life                     160     6 C    
15 Rice Krispies            290     3 C    
16 Honey Smacks              50    15 A    
17 Special K                220     4 A    
18 Wheaties                 180     4 A    
19 Corn Flakes              200     3 A    
20 Honeycomb                210    11 C    

Univariate Visualization

I chose to use two histograms to display the Sodium and Sugar content of various cereal brands because these are single numeric variables.

Code

ggplot(cereal, aes(Sodium)) + 
  geom_histogram(aes(y = ..density..), alpha = 0.5) +
  geom_density(alpha = 0.2, fill="red")

Code

  labs(title = "Sodium Content by Cereal Brand", x = "Sodium")

$x
[1] "Sodium"

$title
[1] "Sodium Content by Cereal Brand"

attr(,"class")
[1] "labels"

Code

ggplot(cereal, aes(Sugar)) + 
  geom_histogram(aes(y = ..density..), alpha = 0.5) +
  geom_density(alpha = 0.2, fill="red")

Code

  labs(title = "Sugar Content by Cereal Brand", x = "Sugar")

$x
[1] "Sugar"

$title
[1] "Sugar Content by Cereal Brand"

attr(,"class")
[1] "labels"

Bivariate Visualization

I chose to use a scatterplot to display the Sodium by Sugar content of various cereal brands because these are numeric variables and the scatterplot can be used to reveal relationships between them.

Code

ggplot(cereal, aes(Sugar, Sodium)) + geom_point()

Code

  labs(title = "Sodium Content by Sugar for Cereal Brands", x = "Sugar", y = "Sodium")

$x
[1] "Sugar"

$y
[1] "Sodium"

$title
[1] "Sodium Content by Sugar for Cereal Brands"

attr(,"class")
[1] "labels"