ABSTRACT
A defence studies borrowed a lot from disciplines, for instance economics, geography or medicine, to help assess the variety of defence issues with quantitative methods. Defence and security studies must deal with a wide variety of information and, to achieve this effectively, may use quantitative methods. Quantitative methods applied to defence studies can provide useful information and are used by defence policymakers, strategists, command and control staffs, and other defence professionals, such as those of the defence industrial base. Risk analysis is the basis for defence strategy planning. It requires estimating the probability and impact of the various threats. Theoretical models combined with statistical methods highlight the relative importance of threats and their interaction. The data used to address defence issues are often complex. Time series can be irregular; variables are generally of heterogeneous types; individuals are often poorly defined.
