About the data

palmerpinguins (https://allisonhorst.github.io/palmerpenguins) is an R package to provide a great dataset for data exploration & visualization, as an alternative to iris.

Let’s look into it !

library(palmerpenguins)
library(dplyr)
library(ggplot2)

The penguins data contains the following

glimpse(penguins)

## Rows: 344
## Columns: 8
## $ species           <fct> Adelie, Adelie, Adelie, Adelie, Adelie, Adelie, Adel~
## $ island            <fct> Torgersen, Torgersen, Torgersen, Torgersen, Torgerse~
## $ bill_length_mm    <dbl> 39.1, 39.5, 40.3, NA, 36.7, 39.3, 38.9, 39.2, 34.1, ~
## $ bill_depth_mm     <dbl> 18.7, 17.4, 18.0, NA, 19.3, 20.6, 17.8, 19.6, 18.1, ~
## $ flipper_length_mm <int> 181, 186, 195, NA, 193, 190, 181, 195, 193, 190, 186~
## $ body_mass_g       <int> 3750, 3800, 3250, NA, 3450, 3650, 3625, 4675, 3475, ~
## $ sex               <fct> male, female, female, NA, female, male, female, male~
## $ year              <int> 2007, 2007, 2007, 2007, 2007, 2007, 2007, 2007, 2007~

How many species ?

We have 3 species into this datasets: Adelie, Gentoo, and Chinstrap that are not equally reparted

penguins %>% 
  count(species)

Interesting Metrics

We can get some interesting mean metrics for each species:

mean_metric <- penguins %>%
  group_by(species) %>%
  select(-year) %>%
  summarize(across(where(is.numeric), mean, na.rm = TRUE))
mean_metric

The Gentoo species is heavier than other !

Is this equally distributed between Sex ?

ggplot(penguins, aes(x = flipper_length_mm,
                            y = body_mass_g)) +
  geom_point(aes(color = sex)) +
  theme_minimal() +
  scale_color_manual(values = c("darkorange","cyan4"), na.translate = FALSE) +
  labs(title = "Penguin flipper and body mass",
       subtitle = "Dimensions for male and female Adelie, Chinstrap and Gentoo Penguins at Palmer Station LTER",
       x = "Flipper length (mm)",
       y = "Body mass (g)",
       color = "Penguin sex") +
  theme(legend.position = "bottom",
        legend.background = element_rect(fill = "white", color = NA),
        plot.title.position = "plot",
        plot.caption = element_text(hjust = 0, face= "italic"),
        plot.caption.position = "plot") +
  facet_wrap(~species)

And where do they live ?

ggplot(penguins, aes(x = island, fill = species)) +
  geom_bar(alpha = 0.8) +
  scale_fill_manual(values = c("darkorange","purple","cyan4"),
                    guide = FALSE) +
  theme_minimal() +
  facet_wrap(~species, ncol = 1) +
  coord_flip()

One of the species lives on all island and the others are specific to one island only.

Acknowledgement

• Alison Horst, and Alison Presman-Hill for the package palmerpinguins and the article content from which the example above are taken and inspired.

• Alison Horst for the two illustrations.

• Source of content: https://allisonhorst.github.io/palmerpenguins