Behaviour of a Small Political Call Market

We present a preliminary overview of a political stock market experiment we have conducted at the Universitaet Passau. This experiment differs from previous work (e.g. the renowned Iowa Electronic Markets) in that it is built on the call market institution rather than on double auction principles. The predictions (for the Bavarian state election in Germany) derived from our market are less accurate than those typically achieved by double auction markets. We suggest, and discuss, a number of reasons for this, outlining some directions for research on our second, and more substantial, political stock market for the German Bundestag election.