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more difficult challenge, but one that is pertinent if we
are to further our understanding of the global finan-
cial markets. Secondly, since real financial markets
include human traders and “robot” automated trad-
ing agent systems, we hope to explore the dynamic
interactions between these groups by introducing hu-
man participants into our experiments. ExPo has been
specifically designed to enable human participation;
and further, since ExPo participants (whether human,
or robot) connect to the exchange using HTTP mes-
saging across a network, ExPo allows geographically
dis-located human participants to sign in via a web
browser and then leave or return at will. Theoretically,
this enables us to run experiments with large num-
bers of participants, over long time periods of days,
weeks, or even months. As far as we are aware, this
has never been done before and has the potential to
provide valuable insight into real world financial mar-
kets.
ACKNOWLEDGEMENTS
The authors would like to thank Tomas Gra
ˇ
zys for
significant development of the ExPo platform. Pri-
mary financial support for Dave Cliff’s research
comes from EPSRC grant number EP/F001096/1;
John Cartlidge is supported by EPSRC grant number
EP/H042644/1.
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