sampling bias, but with markets, the incentive structure tends to make the
forecasts more accurate.
We do not think that prediction markets will replace existing influenza sur-
veillance systems, nor will they eliminate the need for improvements to the
existing systems. Instead, we propose prediction markets as a supplement to
traditional surveillance approaches. Active prediction markets could act as a
“barometer” for emerging infectious diseases. The probabilities generated by
prediction markets could help policymakers and public health officials coor-
dinate resources, facilitate vaccine production, manage stockpiles of medica-
tions, and plan for the allocation of personnel and other resources. Finally,
once a broad group of traders are accustomed to using prediction markets
for one disease, in many situations, they could be recruited to participate in
markets for other infectious diseases, both emerging and reemerging.
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