Computational models are often thought to be brittle, in the sense that slight changes in one area can dramatically alter their results. This fear is perhaps due to the experience of having a computer program crash after some seemingly innocuous input or alteration. Indeed such crashes are rather dramatic, though they are not unique to computational tools. For example, we see similar collapses in a mathematical model when we alter our assumptions about, say, the form of the utility function or the compactness of the strategy space.
