What is Modeling?
This work is about computer-based mathematical modeling tools. But before we can implement these tools, we have to understand modeling and, above all, mathematical modeling. The purpose of this chapter is to give a precise definition of the term model. The overview will begin with general, unspecified notions, and then proceed to more formal concepts. Finally, a short historical digression will be presented to suggest further arguments for the importance of mathematical modeling.
KeywordsSolar System Modeling Language Virtual Object Procedural Knowledge Intersection Problem
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- 13.Popper criticizes this manner of defining simplicity. He thinks that such considerations are entirely arbitrarily [Popper 1976, p. 99]. He also refuses the aesthetic-pragmatic concept of simplicity. Popper identifies these concepts with the concept of degree of falsification [p. 101].Google Scholar
- 14.Aesthetics, being an emotional reaction to simplicity, have an important adaptive function which is in no way the unique privilege of human beings. Charles Darwin stated that some female birds have an aesthetic preference for bright markings on males. For a biological foundation of aesthetics see: Rentschler I., Herzberger B., Epstein D., [ 1988 ], Beauty and Brain, Biological Aspects of Aesthetics, Birkhäuser, Basel.Google Scholar
- 15.The American Eliseo Vivas’ theory of disinterested perception,which asserts that the key concept in aesthetics is disinterestedness does not necessarily contradict the above theory of aesthetics as a motivating force. We have all had the experience that when we concentrate consciously on a problem by forcing an issue, it does not work. Sometimes, we have to relax, to step back from the problem in order to make some progress.Google Scholar
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- 17.It is said that the outstanding American physicist J.W. Gibbs (1839–1903), during a discussion on the question of whether more attention should be given to ancient languages or to mathematics, pronounced in irritation: “But mathematics is also a language.”Google Scholar
- 18.Of course, if “deriving” means “implication” instead of “equivalence” then the consequence is weaker than the antecedence. Knowledge is lost in this case.Google Scholar
- 19.This definition only expresses the declarative part of a problem. We shall extend the definition of model in Chapter 7 to englobe also the algorithmic part. Google Scholar
- 20.Throughout this text, we use the term parameter for the known data in models, and variable for the unknown elements. Since these two terms clashes with well known concepts in programming languages, we use the convention to call parameters in functions and procedures headings always formal parameters. Using these parameters in a function or procedure call will be called actual parameters. The term variable used in programming languages, which is a name for a memory location, will be called memory variable (see also the Glossary).Google Scholar
- 21.A good modern introduction to model theory is: CHANG C.C., KEISLER H.J., , Model Theory. 3rd ed., North-Holland, Amsterdam.Google Scholar
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- 24.The misleading view, that the distinction between model and theory is only a gradual one, is widespread in many scientific communities outside of the philosophy of the science community. According to this view, it is certainly not the complexity nor the size (considering models in operations research which contain many thousands of variables and constraints), nor is it the language, nor the purposes that makes the difference. It is rather the stability over time that distinguishes theories from models. Models are more volatile, subject to frequent changes and modifications [Zimmermann 1987, p. 4].Google Scholar
- 25.David Hilbert (1862–1943) once noted that the content of geometry does not change if we replace the words point, line,and plane by, for example, chair, table,and bar [cited in: Yaglom p. 7]. Wigner  in his famous article stated that “mathematics is the science of skilful operations with concepts and rules invented just for this purpose.”Google Scholar