The reader who has made it this far may feel that a lot of mileage has been squeezed from one simple concept, namely the zero-sum game with non-detection probability or time to detection as the payoff to the verified party. Is this model really justified, or do the many ‘optimal’ inspection strategies that have been derived in the preceding chapters have little relevance to real-world conflicts of interest, with all their ambiguity and complication?

Even under the assumption of illegal behavior, the zero-sum game seems questionable. What about false alarms, for instance? Their avoidance is clearly in both players' interest. And what about the option of legal behavior? In practice the inspectee chooses this option in the vast majority of cases. Surely that fact should influence the inspector's actions. Which inspection strategies deter violations? Can deterrence be quantified?

We approached these questions briefly in Chapter 6 in the context of attributes sampling. Here we shall face them head-on. There is a more general way of analyzing verification problems, one which takes into account such broader questions and which also fortunately legitimizes the results we have obtained in the foregoing chapters. It involves a deeper application of the formalism of non-cooperative games and the associated solution concept of equilibrium strategies. It treats the deterrence aspect in a novel way by examining a class of games in which the inspector announces his verification strategy in advance and in a credible way.