There are several possible methods of investigation. First, all dyadic associations could be analyzed. In this format each alliance organization (for example, NATO), no matter how large, would be decomposed into all of the individual dyadic commitments. Formally, this would imply all of the [N(N - 1)]/2 dyadic possibilities, which is an unrealistic circumstance. The major purpose of such aggregate alliance organizations generally is the protective "umbrella" of the great power (as in NATO), but clearly the adherence of the smaller powers is desired by the great power for security reasons. There is, therefore, an asymmetry in association between small and great powers within the alliance which leads to a far different interpretation for the protective nature of, say, the American-Norwegian association in comparison with the DanishNorwegian. To treat both as equivalent dyads would be unfortunate.