Exploring Equation Space

Peter Whigham
Dept of Information Science, University of Otago

Many disciplines are interested in forming mathematical expressions to
represent relationships in observed data.  Standard statistical techniques
offer approaches to developing equations, however they are often limited in
their form of expression and the types of mathematical functions that can be

This seminar will describe an evolutionary search approach to discovering equations
that can generalise a set of observed data. The talk will focus on multivariate time
series problems from the domain of freshwater ecology. Searching for several different
equation forms, including difference equations and the use of past variables, will be
described.  An example of searching within the constraints of a process-based model
will also be given.  An introduction to formal language theory and genetic programming
will be presented as background to this talk.