Create density plots with ggridges package in R

Packages we will need:

library(tidyverse)
library(ggridges)
library(ggimage)  # to add png images
library(bbplot)   # for pretty graph themes

We will plot out the favourability opinion polls for the three main political parties in Ireland from 2016 to 2020. Data comes from Louwerse and Müller (2020)

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Before we dive into the ggridges plotting, we have a little data cleaning to do. First, we extract the last four “characters” from the date string to create a year variable.

I took this quick function from a StackOverflow response:

substrRight <- function(x, n){
  substr(x, nchar(x)-n+1, nchar(x))}

polls_csv$year <- substrRight(polls_csv$Date, 4)

Next, pivot the data from wide to long format.

More information of pivoting data with dplyr can be found here. I tend to check it at least once a month as the arguments refuse to stay in my head.

I only want to take the main parties in Ireland to compare in the plot.

polls <- polls_csv %>%
  select(year, FG:SF) %>% 
  pivot_longer(!year, names_to = "party", values_to = "opinion_poll")

I went online and found the logos for the three main parties (sorry, Labour) and saved them in the working directory I have for my RStudio. That way I can call the file with the prefix “~/**.png” rather than find the exact location they are saved on the computer.

polls %>% 
  filter(party == "FF" | party == "FG" | party == "SF" ) %>% 
  mutate(image = ifelse(party=="FF","~/ff.png",
 ifelse(party=="FG","~/fg.png", "~/sf.png"))) -> polls_three

Now we are ready to plot out the density plots for each party with the geom_density_ridges() function from the ggridges package.

We will add a few arguments into this function.

We add an alpha = 0.8 to make each density plot a little transparent and we can see the plots behind.

The scale = 2 argument pushes all three plots togheter so they are slightly overlapping. If scale =1, they would be totally separate and 3 would have them overlapping far more.

The rel_min_height = 0.01 argument removes the trailing tails from the plots that are under 0.01 density. This is again for aesthetics and just makes the plot look slightly less busy for relatively normally distributed densities

The geom_image takes the images and we place them at the beginning of the x axis beside the labels for each party.

Last, we use the bbplot package BBC style ggplot theme, which I really like as it makes the overall graph look streamlined with large font defaults.

polls_three %>% 
  ggplot(aes(x = opinion_poll, y = as.factor(party))) +  
  geom_density_ridges(aes(fill = party), 
                      alpha = 0.8, 
                      scale = 2,
                      rel_min_height = 0.01) + 
  ggimage::geom_image(aes(y = party, x= 1, image = image), asp = 0.9, size = 0.12) + 
  facet_wrap(~year) + 
  bbplot::bbc_style() +
  scale_fill_manual(values = c("#f2542d", "#edf6f9", "#0e9594")) +
  theme(legend.position = "none") + 
  labs(title = "Favourability Polls for the Three Main Parties in Ireland", subtitle = "Data from Irish Polling Indicator (Louwerse & Müller, 2020)")
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Comparing mean values across OECD countries with ggplot

Packages we will need:

library(tidyverse)
library(magrittr) # for pipes
library(ggrepel) # to stop overlapping labels
library(ggflags)
library(countrycode) # if you want create the ISO2C variable

I came across code for this graph by Tanya Shapiro on her github for #TidyTuesday.

Her graph compares Dr. Who actors and their average audience rating across their run as the Doctor on the show. So I have very liberally copied her code for my plot on OECD countries.

That is the beauty of TidyTuesday and the ability to be inspired and taught by other people’s code.

I originally was going to write a blog about how to download data from the OECD R package. However, my attempts to download the data leads to an unpleasant looking error and ends the donwload request.

I will try to work again on that blog in the future when the package is more established.

So, instead, I went to the OECD data website and just directly downloaded data on level of trust that citizens in each of the OECD countries feel about their governments.

Then I cleaned up the data in excel and used countrycode() to add ISO2 and country name data.

Click here to read more about the countrycode() package.

First I will only look at EU countries. I tried with all the countries from the OECD but it was quite crowded and hard to read.

I add region data from another dataset I have. This step is not necessary but I like to colour my graphs according to categories. This time I am choosing geographic regions.

my_df %<>%
  mutate(region = case_when(
    e_regiongeo == 1 ~ "Western",
    e_regiongeo == 2  ~ "Northern",
    e_regiongeo == 3  ~ "Southern", 
    e_regiongeo == 4  ~ "Eastern"))

To make the graph, we need two averages:

  1. The overall average trust level for all countries (avg_trust) and
  2. The average for each country across the years (country_avg_trust),
my_df %<>% 
  mutate(avg_trust = mean(trust, na.rm = TRUE)) %>% 
  group_by(country_name) %>% 
  mutate(country_avg_trust = mean(trust, na.rm = TRUE)) %>%
  ungroup()

When we plot the graph, we need a few geom arguments.

Along the x axis we have all the countries, and reorder them from most trusting of their goverments to least trusting.

We will color the points with one of the four geographic regions.

We use geom_jitter() rather than geom_point() for the different yearly trust values to make the graph a little more interesting.

I also make the sizes scaled to the year in the aes() argument. Again, I did this more to look interesting, rather than to convey too much information about the different values for trust across each country. But smaller circles are earlier years and grow larger for each susequent year.

The geom_hline() plots a vertical line to indicate the average trust level for all countries.

We then use the geom_segment() to horizontally connect the country’s individual average (the yend argument) to the total average (the y arguement). We can then easily see which countries are above or below the total average. The x and xend argument, we supply the country_name variable twice.

Next we use the geom_flag(), which comes from the ggflags package. In order to use this package, we need the ISO 2 character code for each country in lower case!

Click here to read more about the ggflags package.

my_df %>%
ggplot(aes(x = reorder(country_name, trust_score), y = trust_score, color = as.factor(region))) +
geom_jitter(aes(color = as.factor(region), size = year), alpha = 0.7, width = 0.15) +
geom_hline(aes(yintercept = avg_trust), color = "white", size = 2)+
geom_segment(aes(x = country_name, xend = country_name, y = country_avg_trust, yend = avg_trust), size = 2, color = "white") +
ggflags::geom_flag(aes(x = country_name, y = country_avg_trust, country = iso2), size = 10) + 
  coord_flip() + 
  scale_color_manual(values = c("#9a031e","#fb8b24","#5f0f40","#0f4c5c")) -> my_plot

Last we change the aesthetics of the graph with all the theme arguments!

my_plot +
 theme(panel.border = element_blank(),
        legend.position = "right",
        legend.title = element_blank(),
        legend.text = element_text(size = 20),
        legend.background = element_rect(fill = "#5e6472"),
        axis.title = element_blank(),
        axis.text = element_text(color = "white", size = 20),
        text= element_text(size = 15, color = "white"),
        panel.grid.major.y = element_blank(),
        panel.grid.minor.y = element_blank(),
        panel.grid.major.x = element_blank(),
        panel.grid.minor.x = element_blank(),
        legend.key = element_rect(fill = "#5e6472"),
        plot.background = element_rect(fill = "#5e6472"),
        panel.background = element_rect(fill = "#5e6472")) +
  guides(colour = guide_legend(override.aes = list(size=10))) 

And that is the graph.

We can see that countries in southern Europe are less trusting of their governments than in other regions. Western countries seem to occupy the higher parts of the graph, with France being the least trusting of their government in the West.

There is a large variation in Northern countries. However, if we look at the countries, we can see that the Scandinavian countries are more trusting and the Baltic countries are among the least trusting. This shows they are more similar in their trust levels to other Post-Soviet countries.

Next we can look into see if there is a relationship between democracy scores and level of trust in the goverment with a geom_point() scatterplot

The geom_smooth() argument plots a linear regression OLS line, with a standard error bar around.

We want the labels for the country to not overlap so we use the geom_label_repel() from the ggrepel package. We don’t want an a in the legend, so we add show.legend = FALSE to the arguments


my_df %>% 
  filter(!is.na(trust_score)) %>% 
  ggplot(aes(x = democracy_score, y = trust_score)) +
  geom_smooth(method = "lm", color = "#a0001c", size = 3) +
  geom_point(aes(color = as.factor(region)), size = 20, alpha = 0.6) +
 geom_label_repel(aes(label = country_name, color = as.factor(region)), show.legend = FALSE, size = 5) + 
scale_color_manual(values = c("#9a031e","#fb8b24","#5f0f40","#0f4c5c")) -> scatter_plot

And we change the theme and add labels to the plot.

scatter_plot + theme(panel.border = element_blank(),
        legend.position = "bottom",
        legend.title = element_blank(),
        legend.text = element_text(size = 20),
        legend.background = element_rect(fill = "#5e6472"),
        text= element_text(size = 15, color = "white"),

        legend.key = element_rect(fill = "#5e6472"),
        plot.background = element_rect(fill = "#5e6472"),
        panel.background = element_rect(fill = "#5e6472")) +
  guides(colour = guide_legend(override.aes = list(size=10)))  +
  labs(title = "Democracy and trust levels", 
       y = "Democracy score",
       x = "Trust level of respondents",
       caption="Data from OECD") 

We can filter out the two countries with low democracy and examining the consolidated democracies.

Thank you for reading!

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Graphing Pew survey responses with ggplot in R

Packages we will need:

library(tidyverse)
library(forcats)
library(ggthemes)

We are going to look at a few questions from the 2019 US Pew survey on relations with foreign countries.

Data can be found by following this link:

We are going to make bar charts to plot out responses to the question asked to American participaints: Should the US cooperate more or less with some key countries? The countries asked were China, Russia, Germany, France, Japan and the UK.

Before we dive in, we can find some nice hex colors for the bar chart. There are four possible responses that the participants could give: cooperate more, cooperate less, cooperate the same as before and refuse to answer / don’t know.

pal <- c("Cooperate more" = "#0a9396",
         "Same as before" = "#ee9b00",
         "Don't know" = "#005f73",
         "Cooperate less" ="#ae2012")

We first select the questions we want from the full survey and pivot the dataframe to long form with pivot_longer(). This way we have a single column with all the different survey responses. that we can manipulate more easily with dplyr functions.

Then we summarise the data to count all the survey reponses for each of the four countries and then calculate the frequency of each response as a percentage of all answers.

Then we mutate the variables so that we can add flags. The geom_flag() function from the ggflags packages only recognises ISO2 country codes in lower cases.

After that we change the factors level for the four responses so they from positive to negative views of cooperation

pew %>% 
  select(id = case_id, Q2a:Q2f) %>% 
  pivot_longer(!id, names_to = "survey_question", values_to = "response")  %>% 
  group_by(survey_question, response) %>% 
  summarise(n = n()) %>%
  mutate(freq = n / sum(n)) %>% 
  ungroup() %>% 
  mutate(response_factor = as.factor(response)) %>% 
  mutate(country_question = ifelse(survey_question == "Q2a", "fr",
ifelse(survey_question == "Q2b", "gb",
ifelse(survey_question == "Q2c", "ru",
ifelse(survey_question == "Q2d", "cn",
ifelse(survey_question == "Q2e", "de",
ifelse(survey_question == "Q2f", "jp", survey_question))))))) %>% 
  mutate(response_string = ifelse(response_factor == 1, "Cooperate more",
ifelse(response_factor == 2, "Cooperate less",
ifelse(response_factor == 3, "Same as before",
ifelse(response_factor == 9, "Don't know", response_factor))))) %>% 
  mutate(response_string = fct_relevel(response_string, c("Cooperate less","Same as before","Cooperate more", "Don't know"))) -> pew_clean

We next use ggplot to plot out the responses.

We use the position = "stack" to make all the responses “stack” onto each other for each country. We use stat = "identity" because we are not counting each reponses. Rather we are using the freq variable we calculated above.

pew_clean %>%
  ggplot() +
  geom_bar(aes(x = forcats::fct_reorder(country_question, freq), y = freq, fill = response_string), color = "#e5e5e5", size = 3, position = "stack", stat = "identity") +
  geom_flag(aes(x = country_question, y = -0.05 , country = country_question), color = "black", size = 20) -> pew_graph

And last we change the appearance of the plot with the theme function

pew_graph + 
coord_flip() + 
  scale_fill_manual(values = pal) +
  ggthemes::theme_fivethirtyeight() + 
  ggtitle("Should the US cooperate more or less with the following country?") +
  theme(legend.title = element_blank(),
        legend.position = "top",
        legend.key.size = unit(2, "cm"),
        text = element_text(size = 25),
        legend.text = element_text(size = 20),
        axis.text = element_blank())

Lollipop plots with ggplot2 in R

Packages we will need:

library(tidyverse)
library(rvest)
library(ggflags)
library(countrycode)
library(ggpubr)

We will plot out a lollipop plot to compare EU countries on their level of income inequality, measured by the Gini coefficient.

A Gini coefficient of zero expresses perfect equality, where all values are the same (e.g. where everyone has the same income). A Gini coefficient of one (or 100%) expresses maximal inequality among values (e.g. for a large number of people where only one person has all the income or consumption and all others have none, the Gini coefficient will be nearly one).

To start, we will take data on the EU from Wikipedia. With rvest package, scrape the table about the EU countries from this Wikipedia page.

Click here to read more about the rvest pacakge

With the gsub() function, we can clean up the different variables with some regex. Namely delete the footnotes / square brackets and change the variable classes.

eu_site <- read_html("https://en.wikipedia.org/wiki/Member_state_of_the_European_Union")

eu_tables <- eu_site %>% html_table(header = TRUE, fill = TRUE)

eu_members <- eu_tables[[3]]

eu_members %<>% janitor::clean_names()  %>% 
  filter(!is.na(accession))

eu_members$iso3 <- countrycode::countrycode(eu_members$geo, "country.name", "iso3c")

eu_members$accession <- as.numeric(gsub("([0-9]+).*$", "\\1",eu_members$accession))

eu_members$name_clean <- gsub("\\[.*?\\]", "", eu_members$name)

eu_members$gini_clean <- gsub("\\[.*?\\]", "", eu_members$gini)

Next some data cleaning and grouping the year member groups into different decades. This indicates what year each country joined the EU. If we see clustering of colours on any particular end of the Gini scale, this may indicate that there is a relationship between the length of time that a country was part of the EU and their domestic income inequality level. Are the founding members of the EU more equal than the new countries? Or conversely are the newer countries that joined from former Soviet countries in the 2000s more equal. We can visualise this with the following mutations:

eu_members %>%
  filter(name_clean != "Totals/Averages") %>% 
  mutate(gini_numeric = as.numeric(gini_clean)) %>% 
  mutate(accession_decades = ifelse(accession < 1960, "1957", ifelse(accession > 1960 & accession < 1990, "1960s-1980s", ifelse(accession == 1995, "1990s", ifelse(accession > 2003, "2000s", accession))))) -> eu_clean 

To create the lollipop plot, we will use the geom_segment() functions. This requires an x and xend argument as the country names (with the fct_reorder() function to make sure the countries print out in descending order) and a y and yend argument with the gini number.

All the countries in the EU have a gini score between mid 20s to mid 30s, so I will start the y axis at 20.

We can add the flag for each country when we turn the ISO2 character code to lower case and give it to the country argument.

Click here to read more about the ggflags package

eu_clean %>% 
ggplot(aes(x= name_clean, y= gini_numeric, color = accession_decades)) +
  geom_segment(aes(x = forcats::fct_reorder(name_clean, -gini_numeric), 
                   xend = name_clean, y = 20, yend = gini_numeric, color = accession_decades), size = 4, alpha = 0.8) +
  geom_point(aes(color = accession_decades), size= 10) +
  geom_flag(aes(y = 20, x = name_clean, country = tolower(iso_3166_1_alpha_2)), size = 10) +
  ggtitle("Gini Coefficients of the EU countries") -> eu_plot

Last we add various theme changes to alter the appearance of the graph

eu_plot + 
coord_flip() +
ylim(20, 40) +
  theme(panel.border = element_blank(),
        legend.title = element_blank(),
        axis.title = element_blank(),
        axis.text = element_text(color = "white"),
        text= element_text(size = 35, color = "white"),
        legend.text = element_text(size = 20),
        legend.key = element_rect(colour = "#001219", fill = "#001219"),
        legend.key.width = unit(3, 'cm'),
        legend.position = "bottom",
        panel.grid.major.y = element_line(linetype="dashed"),
        plot.background = element_rect(fill = "#001219"),
        panel.background = element_rect(fill = "#001219"),
        legend.background = element_rect(fill = "#001219") )

We can see there does not seem to be a clear pattern between the year a country joins the EU and their level of domestic income inequality, according to the Gini score.

Of course, the Gini coefficient is not a perfect measurement, so take it with a grain of salt.

Another option for the lolliplot plot comes from the ggpubr package. It does not take the familiar aesthetic arguments like you can do with ggplot2 but it is very quick and the defaults look good!

eu_clean %>% 
  ggdotchart( x = "name_clean", y = "gini_numeric",
              color = "accession_decades",
              sorting = "descending",                      
              rotate = TRUE,                                
              dot.size = 10,   
              y.text.col = TRUE,
              ggtheme = theme_pubr()) + 
  ggtitle("Gini Coefficients of the EU countries") + 
  theme(panel.border = element_blank(),
        legend.title = element_blank(),
        axis.title = element_blank(),
        axis.text = element_text(color = "white"),
        text= element_text(size = 35, color = "white"),
        legend.text = element_text(size = 20),
        legend.key = element_rect(colour = "#001219", fill = "#001219"),
        legend.key.width = unit(3, 'cm'),
        legend.position = "bottom",
        panel.grid.major.y = element_line(linetype="dashed"),
        plot.background = element_rect(fill = "#001219"),
        panel.background = element_rect(fill = "#001219"),
        legend.background = element_rect(fill = "#001219") )

Replicating Eurostat graphs in R

Packages we will need:

library(eurostat)
library(tidyverse)
library(maggritr)
library(ggthemes)
library(forcats)

In this blog, we will try to replicate this graph from Eurostat!

It compares all European countries on their Digitical Intensity Index scores in 2020. This measures the use of different digital technologies by enterprises.

The higher the score, the higher the digital intensity of the enterprise, ranging from very low to very high. 

For more information on the index, I took the above information from this site: https://ec.europa.eu/eurostat/web/products-eurostat-news/-/ddn-20211029-1

First, we will download the digital index from Eurostat with the get_eurostat() function.

Click here to learn more about downloading data on EU from the Eurostat package.

Next some data cleaning. To copy the graph, we will aggregate the different levels into very low, low, high and very high categories with the grepl() function in some ifelse() statements.

The variable names look a bit odd with lots of blank space because I wanted to space out the legend in the graph to replicate the Eurostat graph above.

dig <- get_eurostat("isoc_e_dii", type = "label")

dig %<>% 
   mutate(dii_level = ifelse(grepl("very low", indic_is), "Very low        " , ifelse(grepl("with low", indic_is), "Low        ", ifelse(grepl("with high", indic_is), "High        ", ifelse(grepl("very high", indic_is), "Very high        ", indic_is)))))

Next I fliter out the year I want and aggregate all industry groups (from the sizen_r2 variable) in each country to calculate a single DII score for each country.

dig %>% 
  select(sizen_r2, geo, values, dii_level, year) %>%  
  filter(year == 2020) %>% 
  group_by(dii_level, geo) %>% 
  summarise(total_values = sum(values, na.rm = TRUE)) %>% 
  ungroup() -> my_dig

I use a hex finder website imagecolorpicker.com to find the same hex colors from the Eurostat graph and assign them to our version.

dii_pal <- c("Very low        " = "#f0aa4f",
             "Low        " = "#fee229",
             "Very high        " = "#154293", 
             "High        " = "#7fa1d4")

We can make sure the factors are in the very low to very high order (rather than alphabetically) with the ordered() function

my_dig$dii_level <- ordered(my_dig$dii_level, levels = c("Very Low        ", "Low        ", "High        ","Very high        "))

Next we filter out the geo rows we don’t want to add to the the graph.

Also we can change the name of Germany to remove its longer title.

my_dig %>% 
  filter(geo != "Euro area (EA11-1999, EA12-2001, EA13-2007, EA15-2008, EA16-2009, EA17-2011, EA18-2014, EA19-2015)") %>% 
  filter(geo != "United Kingdom") %>% 
  filter(geo != "European Union - 27 countries (from 2020)") %>% 
  filter(geo != "European Union - 28 countries (2013-2020)") %>% 
  mutate(geo = ifelse(geo == "Germany (until 1990 former territory of the FRG)", "Germany", geo)) -> my_dig 

And also, to have the same order of countries that are in the graph, we can add them as ordered factors.

my_dig$country <- factor(my_dig$geo, levels = c("Finland", "Denmark", "Malta", "Netherlands", "Belgium", "Sweden", "Estonia", "Slovenia", "Croatia", "Italy", "Ireland","Spain", "Luxembourg", "Austria", "Czechia", "France", "Germany", "Portugal", "Poland", "Cyprus", "Slovakia", "Hungary", "Lithuania", "Latvia", "Greece", "Romania", "Bulgaria", "Norway"), ordered = FALSE)

Now to plot the graph:

my_dig %>% 
  filter(!is.na(country)) %>% 
  group_by(country, dii_level) %>% 
  ggplot(aes(y = country, 
             x = total_values,
             fill = forcats::fct_rev(dii_level))) +
  geom_col(position = "fill", width = 0.7) + 
  scale_fill_manual(values = dii_pal) + 
  ggthemes::theme_pander() +
  coord_flip() +
  labs(title = "EU's Digital Intensity Index (DII) in 2020",
       subtitle = ("(% of enterprises with at least 10 persons employed)"),
       caption = "ec.europa/eurostat") +
  xlab("") + 
  ylab("") + 
  theme(text = element_text(family = "Verdana", color = "#154293"),
        axis.line.x = element_line(color = "black", size = 1.5),
        axis.text.x = element_text(angle = 90, size = 20, color = "#154293", hjust = 1),
        axis.text.y = element_text(color = "#808080", size = 13, face = "bold"),
        legend.position = "top", 
        legend.title = element_blank(),
        legend.text = element_text(color = "#808080", size = 20, face = "bold"),
        plot.title = element_text(size = 42, color = "#154293"),
        plot.subtitle = element_text(size = 25, color = "#154293"),
        plot.caption = element_text(size = 20, color = "#154293"),
        panel.background = element_rect(color = "#f2f2f2"))

It is not identical and I had to move the black line up and the Norway model more to the right with Paint on my computer! So a bit of cheating!

Click to read Part 1, Part 2 and Part 3 of the blog series on visualising Eurostat data

For information on the index discussed in this blog post: https://ec.europa.eu/eurostat/web/products-eurostat-news/-/ddn-20211029-1

Visualize EU data with Eurostat package in R: Part 2 (with maps)

In this post, we will map prison populations as a percentage of total populations in Europe with Eurostat data.

library(eurostat)
library(tidyverse)
library(sf)
library(rnaturalearth)
library(ggthemes)
library(countrycode)
library(ggflags)
library(viridis)
library(rvest)

Click here to read Part 1 about downloading Eurostat data.


prison_pop <- get_eurostat("crim_pris_pop", type = "label")

prison_pop$iso3 <- countrycode::countrycode(prison_pop$geo, "country.name", "iso3c")

prison_pop$year <- as.numeric(format(prison_pop$time, format = "%Y"))

Next we will download map data with the rnaturalearth package. Click here to read more about using this package.

We only want to zoom in on continental EU (and not include islands and territories that EU countries have around the world) so I use the coordinates for a cropped European map from this R-Bloggers post.

map <- rnaturalearth::ne_countries(scale = "medium", returnclass = "sf")

europe_map <- sf::st_crop(map, xmin = -20, xmax = 45,
                          ymin = 30, ymax = 73)

prison_map <- merge(prison_pop, europe_map, by.x = "iso3", by.y = "adm0_a3", all.x = TRUE)

We will look at data from 2000.

prison_map %>% 
  filter(year == 2000) -> map_2000

To add flags to our map, we will need ISO codes in lower case and longitude / latitude.

prison_map$iso2c <- tolower(countrycode(prison_map$geo, "country.name", "iso2c"))

coord <- read_html("https://developers.google.com/public-data/docs/canonical/countries_csv")

coord_tables <- coord %>% html_table(header = TRUE, fill = TRUE)

coord <- coord_tables[[1]]

prison_map <- merge(prison_map, coord, by.x= "iso_a2", by.y = "country", all.y = TRUE)

Nex we will plot it out!

We will focus only on European countries and we will change the variable from total prison populations to prison pop as a percentage of total population. Finally we multiply by 1000 to change the variable to per 1000 people and not have the figures come out with many demical places.

prison_map %>% 
  filter(continent == "Europe") %>% 
  mutate(prison_pc = (values / pop_est)*1000) %>% 
  ggplot() +
  geom_sf(aes(fill = prison_pc, geometry = geometry), 
          position = "identity") + 
  labs(fill='Prison population')  +
  ggflags::geom_flag(aes(x = longitude, 
                         y = latitude+0.5, 
                         country = iso2_lower), 
                     size = 9) +  
  scale_fill_viridis_c(option = "mako", direction = -1) +
  ggthemes::theme_map() -> prison_map

Next we change how it looks, including changing the background of the map to a light blue colour and the legend.

prison_map + 
  theme(legend.title = element_text(size = 20),
        legend.text = element_text(size = 14), 
         legend.position = "bottom",
        legend.background = element_rect(fill = "lightblue",
                                         colour = "lightblue"),
        panel.background = element_rect(fill = "lightblue",
                                        colour = "lightblue"))

I will admit that I did not create the full map in ggplot. I added the final titles and block colours with canva.com because it was just easier! I always find fonts very tricky in R so it is nice to have dozens of different fonts in Canva and I can play around with colours and font sizes without needing to reload the plot each time.

Download EU data with Eurostat package in R: Part 1 (with pyramid graphs)

library(eurostat)
library(tidyverse)
library(janitor)
library(ggcharts)
library(rvest)
library(countrycode)
library(magrittr)

Eurostat is the statistical office of the EU. It publishes statistics and indicators that enable comparisons between countries and regions.

With the eurostat package, we can visualise some data from the EU and compare countries. In this blog, we will create a pyramid graph and a Statista-style bar chart.

First, we use the get_eurostat_toc() function to see what data we can download. We only want to look at datasets.

available_data <- get_eurostat_toc()

available_datasets <- available_data %>% 
  filter(type == "dataset")

A simple dataset that we can download looks at populations. We can browse through the available datasets and choose the code id. We feed this into the get_eurostat() dataset.

demo <- get_eurostat(id = "demo_pjan", 
                     type = "label")

View(demo)

Some quick data cleaning. First changing the date to a numeric variable. Next, extracting the number from the age variable to create a numeric variable.

demo$year <- as.numeric(format(demo$time, format = "%Y"))

demo$age_number <- as.numeric(gsub("([0-9]+).*$", "\\1", demo$age))

Next we filter out the data we don’t need. For this graph, we only want the total columns and two years to compare.


demo %>%
  filter(age != "Total") %>%
  filter(age != "Unknown") %>% 
  filter(sex == "Total") %>% 
  filter(year == 1960 | year == 2019 ) %>% 
  select(geo, iso3, values, age_number) -> demo_two_years

I want to compare the populations of the founding EU countries (in 1957) and those that joined in 2004. I’ll take the data from Wikipedia, using the rvest package. Click here to learn how to scrape data from the Internet.

eu_site <- read_html("https://en.wikipedia.org/wiki/Member_state_of_the_European_Union")

eu_tables <- eu_site %>% html_table(header = TRUE, fill = TRUE)

eu_members <- eu_tables[[3]]

eu_members %<>% janitor::clean_names()  %>% 
filter(!is.na(accession))

Some quick data cleaning to get rid of the square bracket footnotes from the Wikipedia table data.

eu_members$accession <- as.numeric(gsub("([0-9]+).*$", "\\1",eu_members$accession))

eu_members$name_clean <- gsub("\\[.*?\\]", "", eu_members$name)

We merge the two datasets, on the same variable. In this case, I will use the ISO3C country codes (from the countrycode package). Using the names of each country is always tricky (I’m looking at you, Czechia / Czech Republic).

demo_two_years$iso3 <- countrycode::countrycode(demo_two_years$geo, "country.name, "iso3c")

my_pyramid <- merge(demo_two_years, eu_members, by.x = "iso3", by.y = "iso_3166_1_alpha_3", all.x = TRUE)

We will use the pyramid_chart() function from the ggcharts package. Click to read more about this function.

The function takes the age group (we go from 1 to 99 years of age), the number of people in that age group and we add year to compare the ages in 1960 versus in 2019.

The first graph looks at the countries that founded the EU in 1957.

my_pyramid %>%  
  filter(!is.na(age_number)) %>%  
  filter(accession == 1957 ) %>% 
  arrange(age_number) %>% 
  group_by(year, age_number) %>% 
  summarise(mean_age = mean(values, na.rm = TRUE)) %>% 
  ungroup() %>% 
  pyramid_chart(age_number, mean_age, year,
                bar_colors = c("#9a031e", "#0f4c5c")) 
Source: Eurostat

The second graph is the same, but only looks at the those which joined in 2004.

my_pyramid %>%  
  filter(!is.na(age_number)) %>%  
  filter(accession == 2004 ) %>% 
  arrange(age_number) %>% 
  group_by(year, age_number) %>% 
  summarise(mean_age = mean(values, na.rm = TRUE)) %>% 
  ungroup() %>% 
  pyramid_chart(age_number, mean_age, year,
                bar_colors = c("#9a031e", "#0f4c5c")) 

Next we will use the Eurostat data on languages in the EU and compare countries in a bar chart.

I want to try and make this graph approximate the style of Statista graphs. It is far from identical but I like the clean layout that the Statista website uses.

Similar to above, we add the code to the get_eurostat() function and claen the data like above.

lang <- get_eurostat(id = "edat_aes_l22", 
                     type = "label")

lang$year <- as.numeric(format(lang$time, format = "%Y"))

lang$iso2 <- tolower(countrycode(lang$geo, "country.name", "iso2c"))

lang %>% 
  mutate(geo = ifelse(geo == "Germany (until 1990 former territory of the FRG)", "Germany", 
                      ifelse(geo == "European Union - 28 countries (2013-2020)", "EU", geo))) %>% 
  filter(n_lang == "3 languages or more") %>% 
  filter(year == 2016) %>% 
  filter(age == "From 25 to 34 years") %>% 
  filter(!is.na(iso2)) %>% 
  group_by(geo, year) %>% 
  mutate(mean_age = mean(values, na.rm = TRUE)) %>% 
  arrange(mean_age) -> lang_clean

Next we will create bar chart with the stat = "identity" argument.

We need to make sure our ISO2 country code variable is in lower case so that we can add flags to our graph with the ggflags package. Click here to read more about this package

lang_clean %>%
  ggplot(aes(x = reorder(geo, mean_age), y = mean_age)) + 
  geom_bar(stat = "identity", width = 0.7, color = "#0a85e5", fill = "#0a85e5") + 
  ggflags::geom_flag(aes(x = geo, y = -1, country = iso2), size = 8) +
  geom_text(aes(label= values), position = position_dodge(width = 0.9), hjust = -0.5, size = 5, color = "#000500") + 
  labs(title = "Percentage of people that speak 3 or more languages",
       subtitle = ("(% of overall population)"),
       caption = "         Source: Eurostat ") +
  xlab("") + 
  ylab("") -> lang_plot 
  

To try approximate the Statista graphs, we add many arguments to the theme() function for the ggplot graph!

lang_plot + coord_flip() + 
  expand_limits(y = 65) + 
  ggthemes::theme_pander() + 
  theme(plot.background = element_rect(color = "#f5f9fc"),
        panel.grid = element_line(colour = "#f5f9fc"),
        # axis.title.x = element_blank(),
        axis.text.x = element_blank(),
        axis.text.y = element_text(color = "#000500", size = 16),
        # axis.title.y = element_blank(),
        axis.ticks.x = element_blank(),
        text = element_text(family = "Gadugi"),
        plot.title = element_text(size = 28, color = "#000500"),
        plot.subtitle = element_text(size = 20, color = "#484e4c"),
        plot.caption = element_text(size = 20, color = "#484e4c") )

Next, click here to read Part 2 about visualizing Eurostat data with maps

Alternatives to pie charts: coxcomb and waffle charts

Packages we will need

library(tidyverse)
library(rnaturalearth)
library(countrycode)
library(peacesciencer)
library(ggthemes)
library(bbplot)

If we want to convey nuance in the data, sometimes that information is lost if we display many groups in a pie chart.

According to Bernard Marr, our brains are used to equal slices when we think of fractions of a whole. When the slices aren’t equal, as often is the case with real-world data, it’s difficult to envision the parts of a whole pie chart accurately.

Below are some slight alternatives that we can turn to and visualise different values across groups.

I’m going to compare regions around the world on their total energy consumption levels since the 1900s.

First, we can download the region data with information about the geography and income levels for each group, using the ne_countries() function from the rnaturalearth package.

map <- ne_countries(scale = "medium", returnclass = "sf")

Click here to learn more about downloading map data from the rnaturalearth package.

Next we will select the variables that we are interested in, namely the income group variable and geographic region variable:

map %>% 
  select(name_long, subregion, income_gr) %>% as_data_frame() -> region_var

And add a variable of un_code that it will be easier to merge datasets in a bit. Click here to learn more about countrycode() function.

region_var$un_code <- countrycode(region_var$name_long, "country.name", "un") 

Next, we will download national military capabilities (NMC) dataset. These variables – which attempt to operationalize a country’s power – are military expenditure, military personnel, energy consumption, iron and steel production, urban population, and total population. It serves as the basis for the most widely used indicator of national capability, CINC (Composite Indicator of National Capability) and covers the period 1816-2016.

To download them in one line of code, we use the create_stateyears() function from the peacesciencer package.

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states <- create_stateyears(mry = FALSE) %>% add_nmc() 

Click here to read more about downloading Correlates of War and other IR variables from the peacesciencer package

Next we add a UN location code so we can easily merge both datasets we downloaded!

states$un_code <- countrycode(states$statenme, "country.name", "un")
states_df <- merge(states, region_var, by ="un_code", all.x = TRUE)

Next, let’s make the coxcomb graph.

First, we will create one high income group. The map dataset has a separate column for OECD and non-OECD countries. But it will be easier to group them together into one category. We do with with the ifelse() function within mutate().

Next we filter out any country that is NA in the dataset, just to keep it cleaner.

We then group the dataset according to income group and sum all the primary energy consumption in each region since 1900.

When we get to the ggplotting, we want order the income groups from biggest to smallest. To do this, we use the reorder() function with income_grp as the second argument.

To create the coxcomb chart, we need the geom_bar() and coord_polar() lines.

With the coord_polar() function, it takes the following arguments :

  • theta – the variable we map the angle to (either x or y)
  • start – indicates the starting point from 12 o’clock in radians
  • direction – whether we plot the data clockwise (1) or anticlockwise (-1)

We feed in a theta of “x” (this is important!), then a starting point of 0 and direction of -1.

Next we add nicer colours with hex values and label the legend in the scale_fill_manual() function.

I like using the fonts and size stylings in the bbc_style() theme.

Last we can delete some of the ticks and text from the plot to make it cleaner.

Last we add our title and source!

states_df %>% 
  mutate(income_grp = ifelse(income_grp == "1. High income: OECD", "1. High income", ifelse(income_grp == "2. High income: nonOECD", "1. High income", income_grp))) %>% 
  filter(!is.na(income_grp)) %>% 
  filter(year > 1899) %>% 
  group_by(income_grp) %>% 
  summarise(sum_pec = sum(pec, na.rm = TRUE)) %>% 
  ggplot(aes(x = reorder(sum_pec, income_grp), y = sum_pec, fill = as.factor(income_grp))) + 
  geom_bar(stat = "identity") + 
  coord_polar("x", start = 0, direction = -1)  + 
  ggthemes::theme_pander() + 
  scale_fill_manual(
    values = c("#f94144", "#f9c74f","#43aa8b","#277da1"), 
    labels = c("High Income", "Upper Middle Income", "Lower Middle Income", "Low Income"), name = "Income Level") +
  bbplot::bbc_style() + 
  theme(axis.text = element_blank(),
            axis.title.x = element_blank(),
            axis.title.y = element_blank(),
            axis.ticks = element_blank(),
            panel.grid = element_blank()) + 
  ggtitle(label = "Primary Energy Consumption across income levels since 1900", subtitle = "Source: Correlates of War CINC")

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We can compare to the number of countries in each region :

states_df %>% 
  mutate(income_grp = ifelse(income_grp == "1. High income: OECD", "1. High income",
 ifelse(income_grp == "2. High income: nonOECD", "1. High income", income_grp))) %>% 
  filter(!is.na(income_grp)) %>% 
  filter(year == 2016) %>% 
  count(income_grp) %>% 
  ggplot(aes(reorder(n, income_grp), n, fill = as.factor(income_grp))) + 
  geom_bar(stat = "identity") + 
  coord_polar("x", start = 0, direction = - 1)  + 
  ggthemes::theme_pander() + 
  scale_fill_manual(
    values = c("#f94144", "#f9c74f","#43aa8b","#277da1"), 
    labels = c("High Income", "Upper Middle Income", "Lower Middle Income", "Low Income"), 
    name = "Income Level") +
  bbplot::bbc_style() + 
  theme(axis.text = element_blank(),
        axis.title.x = element_blank(),
        axis.title.y = element_blank(),
        axis.ticks = element_blank(),
        panel.grid = element_blank()) + 
  ggtitle(label = "Number of countries per region")

Another variation is the waffle plot!

It is important we do not install the CRAN version, but rather the version in development. I made the mistake of installing the non-github version and nothing worked.

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It was an ocean of error messages.

So, instead, install the following version:

remotes::install_github("hrbrmstr/waffle")
library(waffle)

When we add the waffle::geom_plot() there are some arguments we can customise.

  • n_rows – rhe default is 10 but this is something you can play around with to see how long or wide you want the chart
  • size – again we can play around with this number to see what looks best
  • color – I will set to white for the lines in the graph, the default is black but I think that can look a bit too busy.
  • flip – set to TRUE or FALSE for whether you want the coordinates horizontal or vertically stacked
  • make_proportional – if we set to TRUE, compute proportions from the raw values? (i.e. each value n will be replaced with n/sum(n)); default is FALSE

We can also add theme_enhance_waffle() to make the graph cleaner and less cluttered.

states_df %>% 
  filter(year == 2016) %>% 
  filter(!is.na(income_grp)) %>% 
  mutate(income_grp = ifelse(income_grp == "1. High income: OECD",
 "1. High income", ifelse(income_grp == "2. High income: nonOECD", "1. High income", income_grp))) %>% 
  count(income_grp) %>% 
  ggplot(aes(fill = income_grp, values = n)) +
  scale_fill_manual(
values = c("#f94144", "#f9c74f","#43aa8b","#277da1"), 
labels = c("High Income", "Upper Middle Income", 
"Lower Middle Income", "Low Income"), 
name = "Income Level") +
  waffle::geom_waffle(n_rows = 10, size = 0.5, colour = "white",
              flip = TRUE, make_proportional = TRUE) + bbplot::bbc_style() +  
  theme_enhance_waffle() + 
  ggtitle(label = "Number of countries per region")

We can also look at the sum of military expenditure across each region

states_df %>% 
  filter(!is.na(income_grp)) %>%
  filter(year > 1899) %>% 
  mutate(income_grp = ifelse(income_grp == "1. High income: OECD",
 "1. High income", ifelse(income_grp == "2. High income: nonOECD", 
"1. High income", income_grp))) %>% 
group_by(income_grp) %>%
  summarise(sum_military = sum(milex, na.rm = TRUE)) %>% 
  ggplot(aes(fill = income_grp, values = sum_military)) +
  scale_fill_manual(
    values = c("#f94144", "#f9c74f","#43aa8b","#277da1"), 
    labels = c("High Income", "Upper Middle Income", 
               "Lower Middle Income", "Low Income"), 
    name = "Income Level") +
  geom_waffle(n_rows = 10, size = 0.3, colour = "white",
              flip = TRUE, make_proportional = TRUE) + bbplot::bbc_style() +  
  theme_enhance_waffle() + 
  ggtitle(label = "Sum of military expenditure per region")
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Building a dataset for political science analysis in R, PART 2

Packages we will need

library(tidyverse)
library(peacesciencer)
library(countrycode)
library(bbplot)

The main workhorse of this blog is the peacesciencer package by Stephen Miller!

The package will create both dyad datasets and state datasets with all sovereign countries.

Thank you Mr Miller!

There are heaps of options and variables to add.

Go to the page to read about them all in detail.

Here is a short list from the package description of all the key variables that can be quickly added:

We create the dyad dataset with the create_dyadyears() function. A dyad-year dataset focuses on information about the relationship between two countries (such as whether the two countries are at war, how much they trade together, whether they are geographically contiguous et cetera).

In the literature, the study of interstate conflict has adopted a heavy focus on dyads as a unit of analysis.

Alternatively, if we want just state-year data like in the previous blog post, we use the function create_stateyears()

We can add the variables with type D to the create_dyadyears() function and we can add the variables with type S to the create_stateyears() !

Focusing on the create_dyadyears() function, the arguments we can include are directed and mry.

The directed argument indicates whether we want directed or non-directed dyad relationship.

In a directed analysis, data include two observations (i.e. two rows) per dyad per year (such as one for USA – Russia and another row for Russia – USA), but in a nondirected analysis, we include only one observation (one row) per dyad per year.

The mry argument indicates whether they want to extend the data to the most recently concluded calendar year – i.e. 2020 – or not (i.e. until the data was last available).

dyad_df <- create_dyadyears(directed = FALSE, mry = TRUE) %>%
  add_atop_alliance() %>%  
  add_nmc() %>%
  add_cow_trade() %>% 
  add_creg_fractionalization() 

I added dyadic variables for the

You can follow these links to check out the codebooks if you want more information about descriptions about each variable and how the data were collected!

The code comes with the COW code but I like adding the actual names also!

dyad_df$country_1 <- countrycode(dyad_df$ccode1, "cown", "country.name")

With this dataframe, we can plot the CINC data of the top three superpowers, just looking at any variable that has a 1 at the end and only looking at the corresponding country_1!

According to our pals over at le Wikipedia, the Composite Index of National Capability (CINC) is a statistical measure of national power created by J. David Singer for the Correlates of War project in 1963. It uses an average of percentages of world totals in six different components (such as coal consumption, military expenditure and population). The components represent demographic, economic, and military strength

First, let’s choose some nice hex colors

pal <- c("China" = "#DE2910",
         "United States" = "#3C3B6E", 
         "Russia" = "#FFD900")

And then create the plot

dyad_df %>% 
 filter(country_1 == "Russia" | 
          country_1 == "United States" | 
          country_1 == "China") %>% 
  ggplot(aes(x = year, y = cinc1, group = as.factor(country_1))) +
  geom_line(aes(color = country_1)) +
  geom_line(aes(color = country_1), size = 2, alpha = 0.8) + 
  scale_color_manual(values =  pal) +
  bbplot::bbc_style()

In PART 3, we will merge together our data with our variables from PART 1, look at some descriptive statistics and run some panel data regression analysis with our different variables!

Building a dataset for political science analysis in R, PART 1

When you want to create a dataset for large-n political science analysis from scratch, it can get muddled fast. Some tips I have found helpful to create clean data ready for panel data analysis.

Click here for PART 2 to create dyad-year and state-year variables with conflict, geographic features and alliance data from Correlates of War and Uppsala datasets.

Packages we will need

library(tidyverse)  # of course!
library(states)
library(WDI)
library(countrycode)
library(rnaturalearth)
library(VIM)

The states package by Andreas Beger can provide the skeleton for our panel dataset.

It create a cross-sectional, time-series dataset of independent sovereign countries that stretch back to 1816.

The package includes both the Gleditsch & Ward (G&W) and Correlates of War (COW) lists of independent states.

Click here for a discussion of the difference by Stephen Miller.

With the state_panel function from the states package, we create a data.frame from a start date to an end date, using the following syntax.

state_panel(start, end, by = NULL, partial = "any", useGW = TRUE)

The partial argument indicates how we want to deal with states that is independent for only part of the year. We can indicate “any”, “exact”, “first” or “last”.

For this example, I want to create a dataset starting in 1990 and ending in 2020. I put useGW = FALSE because I want to use the COW list of states.

df <- state_panel(1990, 2020, by = "year", partial = "last", useGW = FALSE)
View(df)

And this is the resulting dataset

So we have our basic data.frame. We can see how many states there have been over the years.

df %>% 
  group_by(year) %>% 
  count() %>%  
  arrange(n) 
# A tibble: 31 x 2
# Groups:   year [31]
    year     n
   <int> <int>
 1  1990   161
 2  1991   177
 3  1992   181
 4  1993   186
 5  1994   187
 6  1995   187
 7  1996   187
 8  1997   187
 9  1998   187
10  1999   190
11  2000   191
12  2001   191
13  2002   192
14  2003   192
15  2004   192
16  2005   192
17  2006   193
18  2007   193
19  2008   194
20  2009   194
# ... with 11 more rows

We can see that the early 1990s saw the creation of many states after the end of the Soviet Union. Since 2011, the dataset levels out at 195 (after the creation of South Sudan)

Next, we can add the country name with the countrycode() function from the countrycode package. We feed in the cowcode variable and add the full country names. Click here to read more about the function in more detail and see other options to add country ISO code, for example.

df$country <- countrycode(df$cowcode, "cown", "country.name")

With our dataset with all states, we can add variables for our analysis

We can use the WDI package to download any World Bank indicator.

Click here for more information about this super easy package.

I’ll first add some basic variables, such as population, GDP per capita and infant mortality. We can do this with the WDI() function. The indicator code for population is SP.POP.TOTL so we add that to the indicator argument. (If we wanted only a few countries, we can add a vector of ISO2 code strings to the country argument).

POP <- WDI(country = "all",
           indicator = 'SP.POP.TOTL',
           start = 1990, 
           end = 2020)

The default variable name for population is the long string, so I’ll quickly change that

POP$population <- POP$SP.POP.TOTL 
POP$SP.POP.TOTL <- NULL

I’ll do the same for GDP and infant mortality

GDP <- WDI(country = "all",
       indicator = 'NY.GDP.MKTP.KD',
       start = 1990, 
       end = 2020)

GDP$gdp <- GD$PNY.GDP.MKTP.KD
GDP$NY.GDP.MKTP.KD <- NULL

INF_MORT <- WDI(country = "all",
       indicator = 'SP.DYN.IMRT.IN',
       start = 1990, 
       end = 2020)

INF_MORT$infant_mortality <- INF_MORT$SP.DYN.IMRT.IN
INF_MORT$SP.DYN.IMRT.IN <- NULL

Next, I’ll bind all the variables them together with cbind()

wb_controls <- cbind(POP, GDP, INF_MORT)

This cbind will copy the country and year variables three times so we can delete any replicated variables:

wb_controls <- wb_controls[, !duplicated(colnames(wb_controls), fromLast = TRUE)] 

When we download World Bank data, it comes with aggregated data for regions and economic groups. If we only want in our dataset the variables for countries, we have to delete the extra rows that we don’t want. We have two options for this.

The first option is to add the cow codes and then filter out all the rows that do not have a cow code (i.e. all non-countries)

wb_controls$cow_code <- countrycode(wb_controls$country, "country.name", 'cown')

Then we re-organise the variables a bit more nicely in the dataset with select() and keep only the countries with filter() and the !is.na argument that will remove any row with NA values in the cow_code column.

df_v2 <- wb_controls %>%
  select(country, iso2c, cow_code, year, everything()) %>%
  filter(!is.na(cow_code))

Alternatively, we can merge the World Bank variables with our states df and it can filter out any row that is not a sovereign, independent state.

In the merge() function, we use by to indicate the columns by which we want to merge the datasets. The all argument indicates which dataset we want to keep and NOT delete rows that do not match. If we typed all = TRUE, it would not delete any rows that do not match.

wb_controls %<>%
  select(cow_code, year, everything()) 

df_v3 <- merge(df, wb_controls, by.x = c("cowcode", "year"), by.y = c("cow_code", "year"), all.x = TRUE)

You can see that df_v2 has 85 more rows that df_v3. So it is up to you which way you want to use, and which countries you want to include each year. The df_v3 contains states that are more likely to be recognised as sovereign. df_v2 contains more territories.

Let’s look at the prevalence of NA values across our dataset.

We can use the plot_missing() function from the states package.

plot_missing(df_v3, ccode = "cowcode")

It is good to see a lot of green!

Let’s add some constant variables, such as geographical information. The rnaturalearth package is great for plotting maps. Click here to see how to plot maps with the package.

For this dataset, we just want the various geography group variables to add to our dataset:

map <- ne_countries(scale = "medium", returnclass = "sf")

We want to take some of the interesting variables from this map object:

map %>% 
  select(admin, economy, income_grp, continent, region_un, subregion, region_wb) -> regions_sf

This regions_sf is not in a data.frame object, it is a simple features dataset. So we delete the variables that make it an sf object and explicitly coerce it to data.frame

regions_sf$geometry<- NULL
regions_df <- as.data.frame(regions_sf)

Finally, we add our COW codes like we did above:

regions_df$cow_code <- countrycode(regions_df$admin, "country.name", "cown")
Warning message:
In countrycode(regions_df$admin, "country.name", "cown") :

Some values were not matched unambiguously: Antarctica, Kashmir, Republic of Serbia, Somaliland, Western Sahara

Sometimes we cannot avoid hand-coding some of our variables. In this case, we don’t want to drop Serbia because the countrycode function couldn’t add the right code.

So we can check what its COW code is and add it to the dataset directly with the mutate function and an ifelse condition:

regions_df %<>% 
  dplyr::mutate(cow_code = ifelse(admin == "Republic of Serbia", 345, cow_code))

If we look at the countries, we can spot a problem. For Cyprus, it was counted twice – due to the control by both Turkish and Greek authorities. We can delete one of the versions because all the other World Bank variables look at Cyprus as one entity so they will be the same across both variables.

regions_df <- regions_df %>% slice(-c(38)) 

Next we merge the new geography variables to our dataset. Note that we only merge by one variable – the COW code – and indicate that we want to merge for every row in the x dataset (i.e. the first dataset in the function). So it will apply to each year row for each country!

df_v4 <- merge(df_v3, regions_df, by.x = "cowcode", by.y = "cow_code", all.x = TRUE)

So far so good! We have some interesting variables all without having to open a single CSV or DTA file!

Let’s look at the NA values in the data.frame

nhanes_miss = VIM::aggr(df_v3,
                   labels = names(df_v3), 
                   sortVars = TRUE,
                   numbers = TRUE)

We with the aggr() function from the VIM package to look at the prevalence of NA values. It’s always good to keep an eye on this and catch badly merged or badly specified datasets!

Click here for PART 2, where we add some Correlates of War data and interesting variables with the peacesciencer package .

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