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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Compare Irish census years with compareBars and csodata package in R

Packages we will need:

library(csodata)
library(janitor)
library(ggcharts)
library(compareBars)
library(tidyverse)

First, let’s download population data from the Irish census with the Central Statistics Office (CSO) API package, developed by Conor Crowley.

You can search for the data you want to analyse via R or you can go to the CSO website and browse around the site.

I prefer looking through the site because sometimes I stumble across a dataset I didn’t even think to look for!

Keep note of the code beside the red dot star symbol if you’re looking around for datasets.

Click here to check out the CRAN PDF for the CSO package.

You can search for keywords with cso_search_toc(). I want total population counts for the whole country.

cso_search_toc("total population")

We can download the variables we want by entering the code into the cso_get_data() function

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irish_pop <- cso_get_data("EY007")
View(irish_pop)

The EY007 code downloads population census data in both 2011 and 2016 at every age.

It needs a little bit of tidying to get it ready for graphing.

irish_pop %<>%  
  clean_names()

First, we can be lazy and use the clean_names() function from the janitor package.

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Next we can get rid of the rows that we don’t want with select().

Then we use the pivot_longer() function to turn the data.frame from wide to long and to turn the x2011 and x2016 variables into one year variable.

irish_pop %>% 
  filter(at_each_year_of_age == "Population") %>% 
  filter(sex == 'Both sexes') %>% 
  filter(age_last_birthday != "All ages") %>% 
  select(!statistic) %>% 
  select(!sex) %>% 
  select(!at_each_year_of_age) -> irish_wide

irish_wide %>% 
  pivot_longer(!age_last_birthday,
    names_to = "year", 
    values_to = "pop_count",
    values_drop_na = TRUE) %>% 
    mutate(year = as.factor(year)) -> irish_long

No we can create our pyramid chart with the pyramid_chart() from the ggcharts package. The first argument is the age category for both the 2011 and 2016 data. The second is the actual population counts for each year. Last, enter the group variable that indicates the year.

irish_long %>%   
  pyramid_chart(age_last_birthday, pop_count, year)

One problem with the pyramid chart is that it is difficult to discern any differences between the two years without really really examining each year.

One way to more easily see the differences with the compareBars function

The compareBars package created by David Ranzolin can help to simplify comparative bar charts! It’s a super simple function to use that does a lot of visualisation leg work under the hood!

First we need to pivot the data.frame back to wide format and then input the age, and then the two groups – x2011 and x2016 – in the compareBars() function.

We can add more labels and colors to customise the graph also!

irish_long %>% 
  pivot_wider(names_from = year, values_from = pop_count) %>% 
  compareBars(age_last_birthday, x2011, x2016, orientation = "horizontal",
              xLabel = "Population",
              yLabel = "Year",
              titleLabel = "Irish Populations",
              subtitleLabel = "Comparing 2011 and 2016",
              fontFamily = "Arial",
              compareVarFill1 = "#FE6D73",
              compareVarFill2 = "#17C3B2") 

We can see that under the age of four-ish, 2011 had more at the time. And again, there were people in their twenties in 2011 compared to 2016.

However, there are more older people in 2016 than in 2011.

Similar to above it is a bit busy! So we can create groups for every five age years categories and examine the broader trends with fewer horizontal bars.

First we want to remove the word “years” from the age variable and convert it to a numeric class variable. We can easily do this with the parse_number() function from the readr package

irish_wide %<>% 
mutate(age_num = readr::parse_number(as.character(age_last_birthday))) 

Next we can group the age years together into five year categories, zero to 5 years, 6 to 10 years et cetera.

We use the cut() function to divide the numeric age_num variable into equal groups. We use the seq() function and input age 0 to 100, in increments of 5.

irish_wide$age_group = cut(irish_wide$age_num, seq(0, 100, 5))

Next, we can use group_by() to calculate the sum of each population number in each five year category.

And finally, we use the distinct() function to remove the duplicated rows (i.e. we only want to keep the first row that gives us the five year category’s population count for each category.

irish_wide %<>% 
  group_by(age_group) %>% 
  mutate(five_year_2011 = sum(x2011)) %>% 
  mutate(five_year_2016 = sum(x2016)) %>% 
  distinct(five_year_2011, five_year_2016, .keep_all = TRUE)

Next plot the bar chart with the five year categories

compareBars(irish_wide, age_group, five_year_2011, five_year_2016, orientation = "horizontal",
              xLabel = "Population",
              yLabel = "Year",
              titleLabel = "Irish Populations",
              subtitleLabel = "Comparing 2011 and 2016",
              fontFamily = "Arial",
              compareVarFill1 = "#FE6D73",
              compareVarFill2 = "#17C3B2") 

irish_wide2 %>% 
  select(age_group, five_year_2011, five_year_2016) %>% 
  pivot_longer(!age_group,
             names_to = "year", 
             values_to = "pop_count",
             values_drop_na = TRUE) %>% 
  mutate(year = as.factor(year)) -> irishlong2

irishlong2 %>%   
  pyramid_chart(age_group, pop_count, year)

Graph linear model plots with sjPlots in R

This blog post will look at the plot_model() function from the sjPlot package. This plot can help simply visualise the coefficients in a model.

Packages we need:

library(sjPlot)
library(kable)

We can look at variables that are related to citizens’ access to public services.

This dependent variable measures equal access access to basic public services, such as access to security, primary education, clean water, and healthcare and whether they are distributed equally or unequally according to socioeconomic position.

Higher scores indicate a more equal society.

I will throw some variables into the model and see what relationships are statistically significant.

The variables in the model are

  • level of judicial constraint on the executive branch,
  • freedom of information (such as freedom of speech and uncensored media),
  • level of democracy,
  • level of regime corruption and
  • strength of civil society.

So first, we run a simple linear regression model with the lm() function:

summary(my_model <- lm(social_access ~ judicial_constraint +
        freedom_information +
        democracy_score + 
        regime_corruption +
        civil_society_strength, 
        data = df))

We can use knitr package to produce a nice table or the regression coefficients with kable().

I write out the independent variable names in the caption argument

I also choose the four number columns in the col.names argument. These numbers are:

  • beta coefficient,
  • standard error,
  • t-score
  • p-value

I can choose how many decimals I want for each number columns with the digits argument.

And lastly, to make the table, I can set the type to "html". This way, I can copy and paste it into my blog post directly.

my_model %>% 
tidy() %>%
kable(caption = "Access to public services by socio-economic position.", 
col.names = c("Predictor", "B", "SE", "t", "p"),
digits = c(0, 2, 3, 2, 3), "html")
Access to public services by socio-economic position
Predictor B SE t p
(Intercept) 1.98 0.380 5.21 0.000
Judicial constraints -0.03 0.485 -0.06 0.956
Freedom information -0.60 0.860 -0.70 0.485
Democracy Score 2.61 0.807 3.24 0.001
Regime Corruption -2.75 0.381 -7.22 0.000
Civil Society Strength -1.67 0.771 -2.17 0.032
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Higher democracy scores are significantly and positively related to equal access to public services for different socio-economic groups.

There is no statistically significant relationship between judicial constraint on the executive.

But we can also graphically show the coefficients in a plot with the sjPlot package.

There are many different arguments you can add to change the colors of bars, the size of the font or the thickness of the lines.

p <-  plot_model(my_model, 
      line.size = 8, 
      show.values = TRUE,
      colors = "Set1",
      vline.color = "#d62828",
      axis.labels = c("Civil Society Strength",  "Regime Corruption", "Democracy Score", "Freedom information", "Judicial constraints"), title = "Equal access to public services distributed by socio-economic position")

p + theme_sjplot(base_size = 20)

So how can we interpret this graph?

If a bar goes across the vertical red line, the coefficient is not significant. The further the bar is from the line, the higher the t-score and the more significant the coefficient!

Make a timeline graph with dates in ggplot2

We will use the geom_segment layer from ggplot2 to make a timeline graph!

This layer takes

  • x and xend for the start of the segment lines
  • y and yend inputs for the end of the segment lines

For our timeline, the x will be the start of each Irish Taoiseach’s term.

The xend will be the end of their term, when they get kicked out of office.

Taoisigh (plural of Taoiseach) are Irish prime ministers and are in charge of the executive branch when their party is in change.

For Ireland, that means that basically every Taoiseach has been the leader of one of the two main parties – Fianna Fail or Fine Gael.

Not very exciting.

Also they have all been men.

This is also not very exciting.

We have a bit more to go with increasing the diversity in Ireland’s top job.

The y argument is the Taoiseach number in office. Although there have been fifteen men that have held the office of Taoiseach, this does not mean that they only held office for one time only.

Ireland has a parliamentary system so when a party loses an election, the former Taoiseach can become the leader of the opposition and hope in the future they can become Taoiseach again. Some men have been Taoiseach two or three times in non-consecutive terms.

When we are adding the labels with the geom_text() layer, I created an order variable which indicates the first time each man took the office of Taoiseach.

This is so I only have the name of each man only once in the graph. If we don’t do this step, if a man held office more than once, their name appears every time on the graph and the plot becomes a crowded mess.

I add the ifelse statement so that the first name appears after the segment line and therefore text does not take up too much room on the left edge of the graph.

Last we use the scale_color_manual() function with nice hex colors for each of the political parties.

time_line <- df %>% 
 ggplot(aes(x = as.Date(start), y = number, color = party_factor)) +
 geom_segment(aes(xend = as.Date(end), yend = number, color =  party_factor), size = 6) +
 geom_text(aes(label = order, hjust = ifelse(taoiseach_number < 2, -0.7, 1.1)), size = 8, show.legend = FALSE) +
 scale_color_manual(values = c("Fine Gael" = "#004266", "Fianna Fáil" = "#FCB322", "Cumann na nGaedheal" = "#D62828"))

I increase the limits of the graph to accommodate the name labels. Most of the time, these extra bits of code in ggplot2 depend on the type of data you have and what fits on the graph plane nicely!

So this stages is often only finished after trial-and-error.

I add a snazzy theme_fivethirtyeight() theme from ggthemes package.

Last, with the theme() function, we can remove most of the elements of the graph to make the graph cleaner.

time_line <- time_line + 
  expand_limits(x = as.Date("1915-01-01")) +
  theme_fivethirtyeight() +
  theme(legend.position = "top",
        legend.title = element_blank(),
        legend.direction = "vertical",
        axis.title.y = element_blank(),
        axis.text.y = element_blank(),
        text = element_text(size = 20)) +
  labs(title = "Taoiseach Terms in Ireland",
 subtitle = "From 1922 to 2021") 

We can also create the pie chart to see which party has held power longest in Ireland.

With dplyr we can subtract the start date from the end date and add all the Taoiseach durations (in days) together with the cumsum() argument.

We then choose the highest duration value for each party with the slice(which.max()) functions.

I was lazy and I just re-wrote the values in a new data.frame and called it counts.

df %>%
  group_by(party_factor) %>% 
  dplyr::summarise(max_count = cumsum(duration_number)) %>%  
  slice(which.max(max_count)) %>% 
  select(party_factor, max_count) %>% 
  arrange(desc(max_count))

counts <- data.frame(group = c("Cumann na nGaedheal", "Fine Gael" ,"Fianna Fáil"), 
                     value = c(3381, 10143, 22539))

Create proportion values for our pie-chart graph. To do this divide value by the sum of the values and multiply by 100.

data <- counts %>% 
  arrange(desc(group)) %>%
  dplyr::mutate(prop = value / sum(value) * 100) 

Change the numeric variables to factors.

data$duration <- as.factor(data$value)
data$party_factor <- as.factor(data$group)

We use the coord_polar() to create the piechart. To learn more, check out the r-graph-gallery page about creating pie-charts:

pie_chart <- ggplot(data, aes(x = ", y = prop, fill = group)) + geom_bar(stat = "identity", width = 1, color = "white") + coord_polar("y", start = 0) +

theme(legend.position = "none") + scale_fill_manual(values = c("Fine Gael" = "#004266", "Fianna Fáil" = "#FCB322", "Cumann na nGaedheal" = "#D62828")) +
 labs(title = "Which party held the office of Taoiseach longest?", subtitle = "From 1922 to 2021")

We can tidy up the plot and get rid of theme elements we don’t want with theme_void()

pie_chart <- pie_chart + theme_void() + theme(legend.title = element_blank(), legend.position = none, text = element_text(size = 40))

I want to add both graphs together so I can save the pie chart with a transparent background with the ggsave() function. I also make sure the lines are not jagged with the type = "cairo" from with Cairo package.

ggsave(pie_chart, file="pie_chart.png", type="cairo", bg = "transparent", width = 50, height = 50, units = "cm")

And we can use canva.com to add them together and create a single chart

And viola!

Examining speeches from the UN Security Council Part 1

Let’s look at how many speeches took place at the UN Security Council every year from 1995 until 2019.

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I want to only look at countries, not organisations. So a quick way to do that is to add a variable to indicate whether the speaker variable has an ISO code.

Only countries have ISO codes, so I can use this variable to filter away all the organisations that made speeches

library(countrycode)

speech$iso2 <- countrycode(speech$country, "country.name", "iso2c")

library(bbplot)

speech %>% 
  dplyr::filter(!is.na(iso2)) %>% 
  group_by(year) %>% 
  count() %>% 
  ggplot(aes(x = year, y = n)) + 
  geom_line(size = 1.2, alpha = 0.4) +
  geom_label(aes(label = n)) +
  bbplot::bbc_style() +
  theme(plot.title = element_text(hjust = 0.5)) +
  labs(title = "Number of speeches given by countries at UNSC")

We can see there has been a relatively consistent upward trend in the number of speeches that countries are given at the UN SC. Time will tell what impact COVID will have on these trends.

There was a particularly sharp increase in speeches in 2015.

We can look and see who was talking, and in the next post, we can examine what they were talking about in 2015 with some simple text analytic packages and functions.

First, we will filter only the year 2015 and count the number of observations per group (i.e. the number of speeches per country this year).

To add flags to the graph, add the iso2 code to the dataset (and it must be in lower case).

Click here to read more about adding circular flags to graphs and maps

speech %>% 
  dplyr::filter(year == 2015) %>% 
  group_by(country) %>% 
  dplyr::summarise(speech_count = n()) -> speech_2015

speech_2015$iso2_lower <- tolower(speech_2015$iso2)

We can clean up the names and create a variable that indicates whether the country is one of the five Security Council Permanent Members, a Temporary Member elected or a Non-,ember.

I also clean up the names to make the country’s names in the dataset smaller. For example, “United Kingdom Of Great Britain And Northern Ireland”, will be very cluttered in the graph compared to just “UK” so it will be easier to plot.

library(ggflags)
library(ggthemes)

speech_2015 %>% 
# To avoid the graph being too busy, we only look at countries that gave over 20 speeches
  dplyr::filter(speech_count > 20) %>% 

# Clean up some names so the graph is not too crowded
  dplyr::mutate(country = ifelse(country == "United Kingdom Of Great Britain And Northern Ireland", "UK", country)) %>%
  dplyr::mutate(country = ifelse(country == "Russian Federation", "Russia", country)) %>%
  dplyr::mutate(country = ifelse(country == "United States Of America", "USA", country)) %>%
  dplyr::mutate(country = ifelse(country == "Republic Of Korea", "South Korea", country)) %>%
  dplyr::mutate(country = ifelse(country == "Venezuela (Bolivarian Republic Of)", "Venezuela", country)) %>% 
  dplyr::mutate(country = ifelse(country == "Islamic Republic Of Iran", "Iran", country)) %>% 
  dplyr::mutate(country = ifelse(country == "Syrian Arab Republic", "Syria", country)) %>% 
 
# Create a Member status variable:
# China, France, Russia, the United Kingdom, and the United States are UNSC Permanent Members
  dplyr::mutate(Member = ifelse(country == "UK", "Permanent", 
  ifelse(country == "USA", "Permanent",
  ifelse(country == "China", "Permanent",
  ifelse(country == "Russia", "Permanent",
  ifelse(country == "France", "Permanent",

# Non-permanent members in their first year (elected October 2014)
  ifelse(country == "Angola", "Temporary (Elected 2014)",
  ifelse(country == "Malaysia", "Temporary (Elected 2014)",              
  ifelse(country == "Venezuela", "Temporary (Elected 2014)",       
  ifelse(country == "New Zealand", "Temporary (Elected 2014)",
  ifelse(country == "Spain", "Temporary (Elected 2014)",                 

# Non-permanent members in their second year (elected October 2013)        
  ifelse(country == "Chad", "Temporary (Elected 2013)",                                                               
  ifelse(country == "Nigeria", "Temporary (Elected 2013)",
  ifelse(country == "Jordan", "Temporary (Elected 2013)",
  ifelse(country == "Chile", "Temporary (Elected 2013)",
  ifelse(country == "Lithuania", "Temporary (Elected 2013)", 
 
# Non members that will join UNSC next year (elected October 2015)          
  ifelse(country == "Egypt", "Non-Member (Elected 2015)",                                                               
  ifelse(country == "Sengal", "Non-Member (Elected 2015)",
  ifelse(country == "Uruguay", "Non-Member (Elected 2015)",
  ifelse(country == "Japan", "Non-Member (Elected 2015)",
  ifelse(country == "Ukraine", "Non-Member (Elected 2015)", 

# Everyone else is a regular non-member           
               "Non-Member"))))))))))))))))))))) -> speech_2015

When we have over a dozen nested ifelse() statements, we will need to check that we have all our corresponding closing brackets.

Next choose some colours for each Memberships status. I always take my hex values from https://coolors.co/

membership_palette <- c("Permanent" = "#e63946", "Non-Member" = "#2a9d8f", "Non-Member (Elected 2015)" = "#a8dadc", "Temporary (Elected 2013)" = "#457b9d","Temporary (Elected 2014)" = "#1d3557")
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And all that is left to do is create the bar chart.

With geom_bar(), we can indicate stat = "identity" because we are giving the plot the y values and ggplot does not need to do the automatic aggregation on its own.

To make sure the bars are descending from most speeches to fewest speeches, we use the reorder() function. The second argument is the variable according to which we want to order the bars. So for us, we give the speech_count integer variable to order our country bars with x = reorder(country, speech_count).

We can change the bar from vertical to horizontal with coordflip().

I add flags with geom_flag() and feed the lower case ISO code to the country = iso2_lower argument.

I add the bbc_style() again because I like the font, size and sparse lines on the plot.

We can move the title of the plot into the centre with plot.title = element_text(hjust = 0.5))

Finally, we can supply the membership_palette vector to the values = argument in the scale_fill_manual() function to specify the colours we want.

speech_2015 %>%  ggplot(aes(x = reorder(country, speech_count), y = speech_count)) + 
  geom_bar(stat = "identity", aes(fill = as.factor(Member))) +
  coord_flip() +
  ggflags::geom_flag(mapping = aes(y = -15, x = country, country = iso2_lower), size = 10) +
  geom_label(mapping = aes( label = speech_count), size = 8) +
  theme(legend.position = "top") + 
  labs(title = "UNSC speeches given in 2015", y = "Number of speeches", x = "") +
  bbplot::bbc_style() +
  theme(text = element_text(size = 20),
  plot.title = element_text(hjust = 0.5)) +
  scale_fill_manual(values =  membership_palette)

In the next post, we will look at the texts themselves. Here is a quick preview.

library(tidytext)

speech_tokens <- speech %>%
  unnest_tokens(word, text) %>% 

  anti_join(stop_words)

We count the number of tokens (i.e. words) for each country in each year. With the distinct() function we take only one observation per year per country. This reduces the number of rows from 16601520 in speech_tokesn to 3142 rows in speech_words_count :

speech_words_count <- speech_tokens %>%
  group_by(year, country) %>%
  mutate(word_count = n_distinct(word)) %>%
  select(country, year, word_count, permanent, iso2_lower) %>%
  distinct() 

Subset the data.frame to only plot the five Permanent Members. Now we only have 125 rows (25 years of total annual word counts for 5 countries!)

permanent_words_summary <- speech_words_count %>% 
  filter(permanent == 1) 

Choose some nice hex colors for my five countries:

five_pal <- c("#ffbc42","#d81159","#8f2d56","#218380","#73d2de")

It is a bit convoluted to put the flags ONLY at the start and end of the lines. We need to subset the dataset two times with the geom_flag() sections. First, we subset the data.frame to year == 1995 and the flags appear at the start of the word_count on the y axis. Then we subset to year == 2019 and do the same

ggplot(data = permanent_word_summary) +
  geom_line(aes(x = year, y = word_count, group = as.factor(country), color = as.factor(country)), 
size = 2) +
  ggflags::geom_flag(data = subset(permanent_word_summary, year == 1995), aes(x = 1995, y = word_count,  country = iso2_lower), size = 9) +
  ggflags::geom_flag(data = subset(permanent_word_summary, 
year == 2019), 
aes(x = 2019, 
y = word_count, 
country = iso2_lower), 
size = 12) + 
  bbplot::bbc_style() +
 theme(legend.position = "right") + labs(title = "Number of words spoken by Permanent Five in the UN Security Council") + 
  scale_color_manual(values = five_pal)

We can see that China has been the least chattiest country if we are measuring chatty with number of words spoken. Translation considerations must also be taken into account. We can see here again at around the 2015 mark, there was a discernible increase in the number of words spoken by most of the countries!

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Improve your visualizations with ggsave in R

When we save our plots and graphs in R, we can use the ggsave() function and specify the type, size and look of the file.

We are going to look two features in particular: anti-aliasing lines with the Cairo package and creating transparent backgrounds.

Make your graph background transparent

First, let’s create a pie chart with a transparent background. The pie chart will show which party has held the top spot in Irish politics for the longest.

After we prepare and clean our data of Irish Taoisigh start and end dates in office and create a doughnut chart (see bottom of blog for doughnut graph code), we save it to our working directory with ggsave().

To see where we set that to, we can use getwd().

ggsave(pie_chart, filename = 'pie_chart.png', width = 50, height = 50, units = 'cm')

If we want to add our doughnut chart to a power point but we don’t want it to be a white background, we can ask ggsave to save the chart as transparent and then we can add it to our powerpoint or report!

To do this, we specify bg argument to "transparent"

ggsave(pie_chart, filename = 'pie_chart_transparent.png', bg = "transparent", width = 50, height = 50, units = 'cm')

This final picture was made in canva.com

Hex color values come from coolors.co

Remove aliasing lines

Aliasing lines are jagged and pixelated.

When we save our graph in R with ggsave(), we can specify in the type argument that we want type = cairo.

I make a quick graph that looks at the trends in migration and GDP from 1960s to 2018 in Ireland. I made the lines extra large to demonstrate the difference between aliased and anti-aliased lines in the graphs.

library(Cairo)
ggsave(mig_trend, file="mig_alias.png", width = 80, height = 50, units = "cm")
ggsave(mig_trend, file="mig_antialias.png", type="cairo-png", dpi = 300,
 width = 80, height = 50, units = "cm")

When we zoom in, we can see the difference due to the anti-aliasing.

First, picture 1 appears far more jagged when we zoom in :

Figure 1: Aliased lines

And after we add Cairo package adjustment, we can see the lines are smoother in figure 2

Figure 2: Anti-aliasing lines

Doughnut graph code:

terms$duration <- as.Date(terms$end) - as.Date(terms$start)
terms$duration_number <- as.numeric(terms$duration)

terms %>%
  group_by(party) %>% 
  dplyr::summarise(max_count = cumsum(duration_number)) %>%  
  slice(which.max(max_count)) %>% 
  select(party, max_count) %>% 
  arrange(desc(max_count))

counts <- data.frame(party = c("Cumann na nGaedheal", "Fine Gael" ,"Fianna Fáil"), 
                     value = c(3381, 10143, 22539))

data <- counts %>% 
  arrange(desc(party)) %>%
  dplyr::mutate(proportion = value / sum(counts$value)*100) %>%
  dplyr::mutate(ypos = cumsum(prop)- 0.35*proportion)

data$duration <- as.factor(data$value)
data$party_factor <- as.factor(data$party)


pie_chart <- ggplot(data, aes(x = 2, y = proportion, fill = party)) +
  geom_bar(stat = "identity", width = 1, color = "white") +
  coord_polar("y", start = 0) +
  xlim(0.5, 2.5) +
  theme(legend.position="none") +
  geom_text(aes(y = ypos-1, label = duration), color = "white", size = 10) +
  scale_fill_manual(values = c("Fine Gael" = "#004266", "Fianna Fáil" = "#FCB322", "Cumann na nGaedheal" = "#D62828")) +
  labs(title = "Which party held the office of Taoiseach longest?",
       subtitle = "From 1922 to 2021")

pie_chart <- pie_chart + theme_void() + theme(legend.title = element_blank(), 
                                 legend.position = "top",
                                 text = element_text(size = 25))

Migration and GNP trend graph code:

migration_trend <- ire_scale %>% 
  dplyr::filter(!is.na(mig_value)) %>% 
  ggplot() + 
  geom_rect(aes(ymin= 0, ymax = -Inf, xmin =-Inf, xmax =Inf), fill = "#9d0208", colour = NA, alpha = 0.07) +
  geom_rect(aes(ymin= 0, ymax = Inf, xmin =-Inf, xmax =Inf), fill = "#2a9d8f", colour = NA, alpha = 0.07) +
  geom_line(aes(x = year, y = gnp_scale), linetype = "dashed", color = "#457b9d", size = 3.5, alpha = 0.7) +
  geom_line(aes(x = year, y = mig_scale), size = 2.5) +
  labs(title = "Relationship between GNP and net migration in Ireland?",
       subtitle = "From 1960 to 2018")


mig_trend <- migration_trend + 
  annotate(geom = "text", x = 1983, y = 1.3, label = "Net Migration", size = 10, hjust = "left") +
  annotate(geom = "curve", x = 1990, y = 1.4, xend = 2000, yend = 1.5, curvature = -0.3, arrow = arrow(length = unit(0.7, "cm")), size = 3) +
  annotate(geom = "text", x = 1995, y = -1.2, label = "GNP", color = "#457b9d", size = 10, hjust = "left") +
  annotate(geom = "curve", x = 1999, y = -1.1, xend = 2000, color = "#457b9d", yend = -0.1, curvature = 0.3, arrow = arrow(length = unit(0.7, "cm")), size = 3)

mig_trend <- mig_trend  + 
  theme_fivethirtyeight() + 
  scale_y_continuous(name = "Net Migration", labels = comma) +
  bbplot::bbc_style() +
  theme(text = element_text(size = 25))

Create a correlation matrix with GGally package in R

We can create very informative correlation matrix graphs with one function.

Packages we will need:

library(GGally)
library(bbplot) #for pretty themes

First, choose some nice hex colors.

my_palette <- c("#005D8F", "#F2A202")
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Next, we can go create a dichotomous factor variable and divide the continuous “freedom from torture scale” variable into either above the median or below the median score. It’s a crude measurement but it serves to highlight trends.

Blue means the country enjoys high freedom from torture. Yellow means the county suffers from low freedom from torture and people are more likely to be tortured by their government.

Then we feed our variables into the ggpairs() function from the GGally package.

I use the columnLabels to label the graphs with their full names and the mapping argument to choose my own color palette.

I add the bbc_style() format to the corr_matrix object because I like the font and size of this theme. And voila, we have our basic correlation matrix (Figure 1).

corr_matrix <- vdem90 %>% 
  dplyr::mutate(
    freedom_torture = ifelse(torture >= 0.65, "High", "Low"),
    freedom_torture = as.factor(freedom_t))
  dplyr::select(freedom_torture, civil_lib, class_eq) %>% 
  ggpairs(columnLabels = c('Freedom from Torture', 'Civil Liberties', 'Class Equality'), 
    mapping = ggplot2::aes(colour = freedom_torture)) +
  scale_fill_manual(values = my_palette) +
  scale_color_manual(values = my_palette)

corr_matrix + bbplot::bbc_style()
Figure 1.
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First off, in Figure 2 we can see the centre plots in the diagonal are the distribution plots of each variable in the matrix

Figure 2.

In Figure 3, we can look at the box plot for the ‘civil liberties index’ score for both high (blue) and low (yellow) ‘freedom from torture’ categories.

The median civil liberties score for countries in the high ‘freedom from torture’ countries is far higher than in countries with low ‘freedom from torture’ (i.e. citizens in these countries are more likely to suffer from state torture). The spread / variance is also far great in states with more torture.

Figure 3.

In Figur 4, we can focus below the diagonal and see the scatterplot between the two continuous variables – civil liberties index score and class equality index scores.

We see that there is a positive relationship between civil liberties and class equality. It looks like a slightly U shaped, quadratic relationship but a clear relationship trend is not very clear with the countries with higher torture prevalence (yellow) showing more randomness than the countries with high freedom from torture scores (blue).

Saying that, however, there are a few errant blue points as outliers to the trend in the plot.

The correlation score is also provided between the two categorical variables and the correlation score between civil liberties and class equality scores is 0.52.

Examining at the scatterplot, if we looked only at countries with high freedom from torture, this correlation score could be higher!

Figure 4.

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Add weights to survey data with survey package in R: Part 2

Click here to read why need to add pspwght and pweight to the ESS data in Part 1.

Packages we will need:

library(survey)
library(srvy)
library(stargazer)
library(gtsummary)
library(tidyverse)

Click here to learn how to access and download ESS round data for the thirty-ish European countries (depending on the year).

So with the essurvey package, I have downloaded and cleaned up the most recent round of the ESS survey, conducted in 2018.

We will examine the different demographic variables that relate to levels of trust in politicians across 29 European countries (education level, gender, age et cetera).

Before we create the survey weight objects, we can first make a bar chart to look at the different levels of trust in the different countries.

We can use the cut() function to divide the 10-point scale into three groups of “low”, “mid” and “high” levels of trust in politicians.

I also choose traffic light hex colors in color_palette vector and add full country names with countrycode() so it’s easier to read the graph

color_palette <- c("1" = "#f94144", "2" = "#f8961e", "3" = "#43aa8b")

round9$country_name <- countrycode(round9$country, "iso2c", "country.name")

trust_graph <- round9 %>% 
  dplyr::filter(!is.na(trust_pol)) %>% 
  dplyr::mutate(trust_category = cut(trust_pol, 
                                     breaks=c(-Inf, 3, 7, Inf), 
                                     labels=c(1,2,3))) %>% 
  mutate(trust_category = as.numeric(trust_category)) %>% 
  mutate(trust_pol_fac = as.factor(trust_category)) %>%
  ggplot(aes(x = reorder(country_name, trust_category))) +
  geom_bar(aes(fill = trust_pol_fac), 
               position = "fill") +
  bbplot::bbc_style() +
  coord_flip() 

trust_graph <- trust_graph + scale_fill_manual(values= color_palette, 
                                      name="Trust level",
                                      breaks=c(1,2,3),
                                      labels=c("Low", "Mid", "High")) 

The graph lists countries in descending order according to the percentage of sampled participants that indicated they had low trust levels in politicians.

The respondents in Croatia, Bulgaria and Spain have the most distrust towards politicians.

For this example, I want to compare different analyses to see what impact different weights have on the coefficient estimates and standard errors in the regression analyses:

  • with no weights (dEfIniTelYy not recommended by ESS)
  • with post-stratification weights only (not recommended by ESS) and
  • with the combined post-strat AND population weight (the recommended weighting strategy according to ESS)

First we create two special svydesign objects, with the survey package. To create this, we need to add a squiggly ~ symbol in front of the variables (Google tells me it is called a tilde).

The ids argument takes the cluster ID for each participant.

psu is a numeric variable that indicates the primary sampling unit within which the respondent was selected to take part in the survey. For example in Ireland, this refers to the particular electoral division of each participant.

The strata argument takes the numeric variable that codes which stratum each individual is in, according to the type of sample design each country used.

The first svydesign object uses only post-stratification weights: pspwght

Finally we need to specify the nest argument as TRUE. I don’t know why but it throws an error message if we don’t …

post_design <- svydesign(ids = ~psu, 
                         strata = ~stratum, 
                         weights = ~pspwght
                         data = round9, 
                         nest = TRUE)

To combine the two weights, we can multiply them together and store them as full_weight. We can then use that in the svydesign function

r2$full_weight <- r2$pweight*r2$pspwght
 

full_design <- svydesign(ids = ~psu, 
                         strata = ~stratum, 
                         weights = ~full_weight,
                         data = round9, 
                         nest = TRUE)
class(full_design)

With the srvyr package, we can convert a “survey.design” class object into a “tbl_svy” class object, which we can then use with tidyverse functions.

full_tidy_design <- as_survey(full_design)
class(full_tidy_design)

Click here to read the CRAN PDF for the srvyr package.

We can first look at descriptive statistics and see if the values change because of the inclusion of the weighted survey data.

First, we can compare the means of the survey data with and without the weights.

We can use the gtsummary package, which creates tables with tidyverse commands. It also can take a survey object

library(gtsummary)
round9 %>% select(trust_pol, trust_pol, age, edu_years, gender, religious, left_right, rural_urban) %>% 
  tbl_summary(include = c(trust_pol, age, edu_years, gender, religious, left_right, rural_urban),
                 statistic = list(all_continuous() ~"{mean} ({sd})"))

And we look at the descriptive statistics with the full_design weights:

full_design %>% 
  tbl_svysummary(include = c(trust_pol, age, edu_years, gender, religious, left_right),
                 statistic = list(all_continuous() ~"{mean} ({sd})"))
WITHOUT weights AND WITH weights (post-stratification and population weights)

We can see that gender variable is more equally balanced between males (1) and females (2) in the data with weights

Additionally, average trust in politicians is lower in the sample with full weights.

Participants are more left-leaning on average in the sample with full weights than in the sample with no weights.

Next, we can look at a general linear model without survey weights and then with the two survey weights we just created.

Do we see any effect of the weighting design on the standard errors and significance values?

So, we first run a simple general linear model. In this model, R assumes that the data are independent of each other and based on that assumption, calculates coefficients and standard errors.

simple_glm <- glm(trust_pol ~ left_right + edu_years + rural_urban + age, data = round9)

Next, we will look at only post-stratification weights. We use the svyglm function and instead of using the data = r2, we use design = post_design .

post_strat_glm <- svyglm(trust_pol ~ left_right + edu_years + rural_urban  + age, design = post_design) 

And finally, we will run the regression with the combined post-stratification AND population weight with the design = full_design argument.

full_weight_glm <- svyglm(trust_pol ~ left_right + edu_years + rural_urban + age, design = full_design))

With the stargazer package, we can compare the models side-by-side:

library(stargazer)
stargazer(simple_glm, post_strat_glm, full_weight_glm, type = "text")

We can see that the standard errors in brackets were increased for most of the variables in model (3) with both weights when compared to the first model with no weights.

The biggest change is the rural-urban scale variable. With no weights, it is positive correlated with trust in politicians. That is to say, the more urban a location the respondent lives, the more likely the are to trust politicians. However, after we apply both weights, it becomes negative correlated with trust. It is in fact the more rural the location in which the respondent lives, the more trusting they are of politicians.

Additionally, age becomes statistically significant, after we apply weights.

Of course, this model is probably incorrect as I have assumed that all these variables have a simple linear relationship with trust levels. If I really wanted to build a robust demographic model, I would have to consult the existing academic literature and test to see if any of these variables are related to trust levels in a non-linear way. For example, it could be that there is a polynomial relationship between age and trust levels, for example. This model is purely for illustrative purposes only!

Plus, when I examine the R2 score for my models, it is very low; this model of demographic variables accounts for around 6% of variance in level of trust in politicians. Again, I would have to consult the body of research to find other explanatory variables that can account for more variance in my dependent variable of interest!

We can look at the R2 and VIF score of GLM with the summ() function from the jtools package. The summ() function can take a svyglm object. Click here to read more about various functions in the jtools package.

Sarcastic Nancy Pelosi GIF by MOODMAN - Find & Share on GIPHY