A lot has been spoken and written about the Wall Street Plunge, David Luckham raised the question about the role of event processing systems in prevention and/or postmortem analysis of understanding how such a situation happened. I am not sure exactly how much event processing system have been part of the reason of causing this plunge in the first place, but here we have an interesting challenge, the challenge is that we need to understand causality in a real event cloud, where the events are part of multiple systems. The nature of the challenge is twofold:
First: Each of the automated trading systems logic is, of course, not transparent, since they are used as competitive edge by the traders, thus it is difficult to know how various systems would function, and there will be a need to learn their logic (which can be constantly changed) based on their actual behavior;
Second: The logic of the various systems is expressed in various ways, and there is no standard causality model that can be used across systems.
This can be one of the challenges that we can put into the challenges of the next generation of event processing systems, that we plan to discuss in Dagstuhl.