Behavioral Modeling and Simulation From Individuals to Societies (2008) / Chapter Skim
Currently Skimming:
Part III: ADDRESSING UNMET MODELING NEEDS, 10 Pitfalls, Lessons Learned, and Future Needs
Part III: ADDRESSING UNMET MODELING NEEDS, 10 Pitfalls, Lessons Learned, and Future Needs
Pages 337-355
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 337... ...
Part III ADDRESSING UNMET MODELING NEEDS 337
|
From page 339... ...
In this chapter we take a step back from this detail and summarize the findings of the committee in the form of lessons learned and future needs if IOS models are to live up to their potential for delivering useful results. Given that most IOS models are in early phases of development, a clear set of best practices has not yet emerged.
|
From page 340... ...
For other applications, such as predicting broader societal reactions, game theory approaches to cultures can lead to such problems as characterizing cultures as necessarily moving toward or existing in an equilibrium state or assuming that conflict involves two parties. In reality, cultures are rarely in equilibrium; changes in technology, resources, and migration all impact culture; and the implications of conflict for a particular society rarely involve just two parties.
|
From page 341... ...
Based on the purpose of the model and the application domain, more collaborative cross-disciplinary efforts in an integrated community of interest are needed to ensure that model developers do not simply rely on the set of variables with which they are most familiar. All-Purpose Models That Ultimately Serve No Purpose Universal scope or "Swiss army knife" models attempt to solve, via large-scale software development, an entire set of wide-ranging concerns.
|
From page 342... ...
In retrospect, it is temptingly easy to build static interoperability solutions if most of the information transferred is physics-based. As one moves into the realm of modeling human and organizational behavior and begins to include cultural, network, emotional, cognitive, and psychological models, one needs to build models as encapsulated smaller model components that can be dynamically linked together rather than trying to create one large source code component (Pratt and Henninger, 2002)
|
From page 343... ...
Early M&S efforts usually modeled physical properties exclusively, so verification consisted of being able to look at the source code and say, "yes, the source appears to implement the mathematics of the physical model." For IOS models, there is no easy path to verification. One can look at the source code but cannot say "yes, the source appears to implement the mathematics of the human or organizational model" because the techniques typically used for such models are code-based and not closed-form mathematics.
|
From page 344... ...
However, we think that accreditation decisions for IOS models should be based on a better understanding and explication of the limitations and usages for such models, as well as a set of VV&A requirements that are appropriately tailored to the special nature of such models. Lessons Learned and Future Needs: Failure to appreciate the extent to which IOS models differ from physical models has led to inappropriate expectations regarding VV&A for IOS models.
|
From page 345... ...
A better integrated multidisciplinary community of interest in IOS modeling, with greater availability of empirical data and more extensive docking of alternative models around common applications, could protect
|
From page 346... ...
As a result, we often see standalone network models that do not incorporate cognitive, cultural, or other processes. Another example of a heavily structuralist approach that ignores process would be a model that uses Hofstede's Big Five personality structure (see Cultural Models in Chapter 3)
|
From page 347... ...
, or not relying on strong theory for guidance. Modelers who are not well versed in a field will have little basis for choosing appropriate variables and will be especially vulnerable to suggestions to add this or that variable to increase realism.
|
From page 348... ...
As with the extreme parsimony pitfall of one-dimensional models, better methods, including comparative studies of alternative models for a common problem, are needed to determine which variables should be included in a model to generate the most useful results. Pitfalls in Dealing with Uncertainty and Adaptation The problems in this section are based on unrealistic expectations of how much uncertainty reduction is plausible in modeling human and organizational behavior, as well as on poor choices in handling the changing nature of human structures and processes.
|
From page 349... ...
Lessons Learned and Future Needs: When actions must be taken in social situations, IOS models can potentially be used to highlight the range of possible outcomes associated with each considered course of action, together with probability assessments clarifying the likelihood of these possible outcomes. Point predictions are generally misleading and incomplete.
|
From page 350... ...
Lessons Learned and Future Needs: When feasible, treat IOS structures as variables or as parameters that can be adjusted, rather than as hardcoded fixed attributes that can be altered only by rewriting the source code. Parameters and assumptions will change as a situation evolves, including adversary knowledge of the assumptions.
|
From page 351... ...
, such models are unlikely to be adequate to inform interventions designed to strengthen social structures that help prevent a crowd from becoming a mob. Moreover, a flock of birds is not the same as one big bird; crowds of people do not necessarily behave like one big person.
|
From page 352... ...
Assemblage of Parts Recognizing the problems inherent in universal scope models (see above) , many in the modeling community have embraced the goal of linking together component models (which may focus, for example, on a specific aspect of human affect or on culture)
|
From page 353... ...
In creating such federated models, modelers need to be aware that straightforward snap-together assembly will yield sensible results only when assumptions of additivity and functional independence are tenable, and they often are not. Complex system analysis has shown repeatedly that the connections among the federated components are themselves components to be modeled.
|
From page 354... ...
The committee thinks that a federated modeling approach, in which different models at different levels are linked together and component submodels can be swapped in and out, are promising for attacking complex IOS modeling problems. Considerable research needs to be done to make this federated vision a reality, however.
|
From page 355... ...
It is important also to avoid raising expectations about the capabilities of IOS models beyond what they can realistically deliver. References Bennington, R.W.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.