THE list of losers from Britain’s vote to leave the European Union is long indeed, but very far down on it are evangelisers for the accuracy of prediction markets. It is an article of faith among economists that betting markets on politics provide by far the most reliableforecast of future events, easily outclassing bothpolls and panels of experts. Yet for the two most important political developments of 2016, and arguably of the past few years—Brexit and Donald Trump winning the Republican nomination for America’s presidency—simple polling averages have put punters to shame.
