Suchergebnisse

Italian cabinets (governi) fall from power in a seemingly haphazard pattern, thus defying most deterministic analyses of their durability. This analysis views Italian government longevity as essentially indeterminate, or stochastic, and it applies the theory of "political reliability" to explain the probability that an Italian government will be in power at time t after it was formed. An exponential survival model R = e−kt, with constant government breakdown rate k = .021 per week, is developed, estimated, tested, and discussed. It is shown that Italian governments have a half-life (τ) of approximately 32.8 weeks, after which their political reliability drops below .50, and their mean duration is 47.7 weeks, so the probability that an Italian government will survive as long as the average is only 36.8%. Theoretical aspects of the model are also discussed, together with characteristic features of exponential political reliability, such as lifetime density, political mortality, and government downfall rate, as well as the systems reliability and crisis process characteristic of Italian governments.

Credibility plays a central role in the classical theory of strategic nuclear deterrence, as well as in many types of social and international relations. This article presents probability models of credibility for survival-retaliation, Wohlstetter-type, and generalized "chain" deterrent threats. Both scenario and systems analysis of these models indicate that (1) only moderate credibility occurs even when very high levels of performance are insured in actions necessary to implement the threat; (2) variations in performance levels induce a destabilizing, more than proportional, amplified variation on overall credibility; and (3) this hyperweakening effect is largest in complex threats. In sum, intuitive estimation of deterrence credibility is severely unreliable, since credibility is weaker than the weakest link in a deterring chain of events. The models are extended and generalized to calculate the credibility of complex systems of deterrent threats, such as the "strategic nuclear triads" deployed by the United States, USSR, United Kingdom, and France, as well as other general deterrents having "serial" and/or "parallel" systems of threats. Special "bottleneck effects" induced by the National Command Authority (NCA) on C3I are emphasized.