Load V-Dem data

Loads selected country-year variables from the V-Dem dataset provided by the vdemdata package. The returned data can use either COW or Gleditsch-Ward country codes.

Usage

load_vdem_data(
  vars = NULL,
  start_year = 1945,
  end_year = 2019,
  coding_system = c("cow", "gw")
)

Source

Varieties of Democracy (V-Dem) Project. Please cite V-Dem when using these data.

Arguments

vars

Character vector of V-Dem variable names to include. If NULL, a default set of civil society, repression, civil liberties, democracy, corruption, and rule-of-law indicators is returned.

start_year

Integer. First year to include.

end_year

Integer. Last year to include.

coding_system

Character. Country coding system to use. Either "cow" for Correlates of War codes or "gw" for Gleditsch-Ward codes.

Value

A data frame with country-year V-Dem indicators. If coding_system = "cow", the data frame contains a cow column. If coding_system = "gw", it contains a gw column.

Details

This function requires the vdemdata package. If it is not installed, install it with:

remotes::install_github("vdeminstitute/vdemdata"). Because vdemdata is not distributed through CRAN, it is always checked conditionally.

For coding_system = "gw", V-Dem COW codes are converted to Gleditsch-Ward codes using countrycode::countrycode().

References

Coppedge, M., Gerring, J., Knutsen, C. H., Lindberg, S. I., Teorell, J., Altman, D., Bernhard, M., Fish, M. S., Glynn, A., Hicken, A., et al. (2025). V-Dem [Country-Year/Country-Date] Dataset v15. Varieties of Democracy.

Examples

if (requireNamespace("vdemdata", quietly = TRUE)) {
vdem_cow <- load_vdem_data(coding_system = "cow")

vdem_selected <- load_vdem_data(
  vars = c("v2x_polyarchy", "v2x_libdem", "v2x_rule"),
  coding_system = "cow"
)

vdem_gw <- load_vdem_data(
  vars = c("v2x_polyarchy", "v2x_libdem"),
  coding_system = "gw"
)
}