Free Riding Reconsidered: The Influence of Space and Time on NATO Member States’ Defence Spending

31 August 2023, Version 1
This content is an early or alternative research output and has not been peer-reviewed at the time of posting.


Concerns over free riding are widespread in alliances, in particular NATO. An intuitive approach to analyzing free riding is treating it as spatial interdependence between the allies: How does a country’s defence spending react to changes in its allies’ military expenditures? Recent work has found a significant negative response for NATO allies and implied that the alliance suffers from substantial free riding. However, this research does not quantify the concerned effect. Furthermore, it does not adequately account for temporal dependence, which risks bias in the parameter of spatial interdependence. Directly accounting for temporal dependence provides a meaningfully different picture of the within-alliance dynamics, revealing that the long-run effect of free riding is indeed more significant than its short-run effect, as suggested by static spatial (autoregressive) models. We discuss the relevant practical and theoretical implications.  


Free riding
NATO member states
spatial interdependence
long-run spatial effects


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.