Add population data to a state panel — add

Joins country-year population data onto an existing state panel. The coding system and year range are detected automatically from the panel.

Usage

add_population(panel, dataset = c("wpp", "nmc", "fariss"))

Arguments

panel: A data frame produced by build_states_panel().
dataset: Dataset to use: "wpp" (default), "nmc", or "fariss". See load_population_data() for details and added columns.

Value

The input panel with population columns added via left join.

References

United Nations, Department of Economic and Social Affairs, Population Division. (2024). World Population Prospects 2024. https://population.un.org/wpp/

Fariss, C. J., Anders, T., Markowitz, J. N., & Barnum, M. (2022). New estimates of over 500 years of historic GDP and population data. Journal of Conflict Resolution, 66(3), 553-591. doi:10.1177/00220027211054432

Singer, J. D., Bremer, S., & Stuckey, J. (1972). Capability distribution, uncertainty, and major power war, 1820-1965. In B. Russett (Ed.), Peace, War, and Numbers (pp. 19-48). Sage.

Singer, J. D. (1988). Reconstructing the Correlates of War dataset on material capabilities of states, 1816-1985. International Interactions, 14, 115-132.

Examples

panel <- build_states_panel(1990, 2010, coding_system = "cow") |>
  add_population(dataset = "wpp")

panel <- build_states_panel(1990, 2010, coding_system = "cow") |>
  add_population(dataset = "nmc")