Add military expenditure data to a state panel — add_military

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

Usage

add_military_expenditure(panel, dataset = c("sipri", "nmc", "barnum"))

Arguments

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

Value

The input panel with military expenditure columns added via left join.

References

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.

Stockholm International Peace Research Institute. (2025). SIPRI Military Expenditure Database. doi:10.55163/CQGC9685

Barnum, M., Fariss, C. J., Markowitz, J. N., & Morales, G. (2025). Measuring arms: Introducing the Global Military Spending Dataset. Journal of Conflict Resolution, 69(2-3), 540-567. doi:10.1177/00220027241232964

Examples

panel <- build_states_panel(1990, 2010, coding_system = "cow") |>
  add_military_expenditure()

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