A fundamental objective of Artificial Intelligence (AI) is the creation
of in- telligent computer programs. In more modest terms AI is simply
con- cerned with expanding the repertoire of computer applications into
new domains and to new levels of efficiency. The motivation for this
effort comes from many sources. At a practical level there is always a
demand for achieving things in more efficient ways. Equally, there is
the technical challenge of building programs that allow a machine to do
something a machine has never done before. Both of these desires are
contained within AI and both provide the inspirational force behind its
development. In terms of satisfying both of these desires there can be
no better example than machine learning. Machines that can learn have an
in-built effi- ciency. The same software can be applied in many
applications and in many circumstances. The machine can adapt its
behaviour so as to meet the demands of new, or changing, environments
without the need for costly re-programming. In addition, a machine that
can learn can be ap- plied in new domains with the genuine potential for
innovation. In this sense a machine that can learn can be applied in
areas where little is known about possible causal relationships, and
even in circumstances where causal relationships are judged not to
exist. This last aspect is of major significance when considering
machine learning as applied to fi- nancial forecasting.