Transparency International, an anti-corruption NGO, pioneered this field with the CPI, first released in 1995. This work is often credited with breaking a taboo and forcing the issue of corruption into high level development policy discourse. Transparency International currently publishes three measures, updated annually: a CPI (based on aggregating third-party polling of public perceptions of how corrupt different countries are); a Global Corruption Barometer (based on a survey of general public attitudes toward and experience of corruption); and a Bribe Payers Index, looking at the willingness of foreign firms to pay bribes. The Corruption Perceptions Index is the best known of these metrics, though it has drawn much criticism and may be declining in influence. In 2013 Transparency International published a report on the "Government Defence Anti-corruption Index". This index evaluates the risk of corruption in countries' military sector.
Which index studies the correlation of corruption and military in a country?
Government Defence Anti-corruption Index