Most of the interest in using mathematical models in finance and economics involves models based
on hypothetical causal relationships described by quantitative mathematical functions. When these
models work they may reflect substantial understanding of the system being simulated and provide a
wealth of information about the internal relationships of the various factors included in the model. Many
of these models have mathematical characteristics which allow them to be solved for optimal results. In
the areas of finance and economics, however, the quality of data is often so poor and the complexities of
the relationships so difficult to express that such models frequently seem to be unreliable
oversimplifications of the real world.
Another scientific tradition, empirical modeling, should then be considered for wider utilization in the
areas of finance and economics. Empirical models may be of value when the more formal theoretical
models are deemed inadequate because of high uncertainties or an inability to adequately express the
complexities. Empirical models are developed by analyzing experimental data (in the case of finance and
economics, historical data).
These models provide little insight or understanding of the cause and effect relationships of the process
being studied, but they do recognize identifiable events which can then predict other events in the process
with various degrees of accuracy. The methodology of theoretical modeling relies on the statistical
relevance of quantitative results derived from mathematical functions used to test hypothetical causal
relationships. Empirical modeling simply tests the statistical relevance of qualitative correspondence
between observed events.
To the extent that the model is accurate, an empirical model may be all that is required by its users. A
good analogy may be found in the field of instrumentation. When the EKG was first used in monitoring
the heart, the recorder would print results on a moving tape which initially looked like nothing more than
oscillating pen strokes. The instrument was recording a great deal of information but no we knew how to
read and interpret it. Eventually, after studying thousands of cases, analysts learned how to read and
interpret the squiggles. Different patterns reflect different types of heart conditions. The results won't
always be identified correctly, but generally speaking, the test has proved to be reliable and useful. The
useful knowledge about the technique was developed empirically. That is actually how most theoretical
modeling begins. To quote Karl Brunner on methodology in economics: "We begin with empirical
regularities and go backward to more and more complicated hypotheses and theories."
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