# Practical Worksheet

As mentioned within the session setup, load the following packages using the `library()` function. Additionally, as we will be using a data set with large numbers, set scipen to 999 using the option function.

``````  library(tidyverse)
library(RColorBrewer)

options(scipen = 999)``````

Furthermore, for the purpose of this session, we will be using data from the World Bank Open Data. In particular we will be using a collection of variables from 1999, these variables were selected to provide us plenty of room to explore!

``WDB_1999 <- read_csv("data/WDB_1999.csv")``

It includes the following variables:

• Country Name (Country Name)
• Country Code (Country Code)
• Continent (Continent)
• Year (Year)
• Population (Pop)
• Female Population (Pop.fe)
• Male Population (Pop.ma)
• Birth Rate, crude per 1000 people (birthrate)
• Death Rate, crude per 1000 people (deathrate)
• Life Expectancy at Birth in years (lifeexp)
• Female Life Expectancy at Birth in years (lifeexp.fe)
• Male Life Expectancy at Birth in years (lifeexp.ma)
• Educational Spending, percentage of GDP (ed.spend)
• Compulsory Education Duration in Years (ed.years)
• Labour Force Total (labour)
• Literature Rate in adults, percentage % (lit.rate.per)
• CO2 Emissions, kt (co2)
• Gross Domestic product, \$ (gdp)
• Unemployment, percentage of total labour force (unemp)
• Female Unemployment, percentage of total labour force (unemp.fe)
• Male Unemployment, percentage of total labour force (unemp.ma)
• Health Expenditure per capita, \$ (health.exp)
• Hospital Beds per 1000 people (medbeds)
• Number of Surgical Procedures per 1000 people (surg.pro)
• Number of Nurses & Midwives per 1000 people (nurse.midwi)

Section 1: ggplot2 vs plot

Exercise 1: Plotting birthrate against deathrate using both the `plot()` and `ggplot()` function, discuss which has more potential in displaying data clearly.

Exercise 2: Expand the plot to group these points by Continent, which provides us with more information and is easier to achieve?

Section 2: Scatter Plots in ggplot

Exercise 3: Change the size parameter to ed.years to see if there is a trend between amount of years in Education and the Birth and Death Rate, set the alpha parameter to 0.5 to clearly see the relationships.

Exercise 4: Change the Labels on the X and Y axisâ€™ and provide a suitable title for the graph

Section 3: Bar Charts and Histograms

Exercise 5: Using the parameter `stat = "identity"` within the `geom_bar()` function, create a bar chart of `Continent` plotted against the mean `birthrate` or `deathrate`

Exercise 6: Using the function `geom_histogram()` create a histogram of the birthrate and deathrate

Section 4: Adding density plots to Histograms

Exercise 7: Using the plot created in exercise 6, add the y-variable `..density..` and `binwidth = 1` to `geom_histogram()` in addition to adding `geom_density()` to add density lines to the Histogram

Exercise 8: Add the parameter, `adjust = 2` in the density plot, to smooth this link and make it more easily interpretable

Section 5: Extra Useful Tips and Functions

Exercise 9: Add a `legends()` and `breaks()` to a plot

Exercise 10: Use the `ggsave()` function to save your last plot