However, this analysis does not take uncertainty into account. Since the revenue functions are only a (possibly rough) estimate, the actual revenue functions may be quite different. For any level of uncertainty (or "horizon of uncertainty") we can define an envelope within which we assume the actual revenue functions are. Higher uncertainty would correspond to a more inclusive envelope. Two of these uncertainty envelopes, surrounding the revenue function of the red team, are represented in Figure 3. As illustrated in Figure 4, the actual revenue function may be any function within a given uncertainty envelope. Of course, some instances of the revenue functions are only possible when the uncertainty is high, while small deviations from the estimate are possible even when the uncertainty is small.