International Relations Theory
Since World War II, extensive efforts have been made to devise a quantitative measurement of national power (see Tellis 2000). These metrics typically use or combine statistics related to the economic, military, demographic, and geographic characteristics of a country into a single number to facilitate inter-country comparisons. There are many formulas that have been developed, taking different factors into consideration and often based upon data that is readily available. Despite this diversity, most definitions produce similar rank-order results (Tellis, ch. 3, citing Merritt and Zinnes).
One well known example is Singer’s (1972) Composite Indicator of National Capability, or CINC:
CINC = (ME + MP + E + TP + UP + ISP) / 6
ME is military expenditure,
MP is military personnel,
E is energy consumption,
TP is total population,
UP is urban population, and
ISP is iron and steel production. All values are the individual state’s percentages of total world capacity. CINC enables comparisons across a broad time span, and the Correlates of War Project has calculated it for every country from 1870 to 2012. On the other hand, the inclusion of iron and steel production seems arbitrary in light of subsequent technological developments, and CINC may not be the appropriate metric for analyzing contemporary situations.
Also noteworthy, due to who created it, the CIA's Strategic Assessments Group uses GDP, population, defense spending, and technological innovation to determine a nation's share of global power (Treverton 2005).
These traditional approaches do not seem to derive from any overarching theory of power or the dynamics of how power balances change over time.
Network Theory in International Relations
- Jang (2020) applies network centrality measures to trade data to evaluate centrality of the U.S. and China in various sectors.
- Maoz (2011) combines network centrality with voting theory (n-person cooperative games) to develop a metric and apply it to international conflict and voting.
- Maoz (2004) seeks to fuse realism and liberalism around the concept of status inconsistency.
- Walther (2016) applies network theory to a violent conflict.