"Trader lost millions apparently trying to manipulate Intrade data to favour Mitt Romney" http://t.co/8n11xSshu8 @MSmithsonPB

— Gavin Jackson (@GavinHJackson) September 24, 2013

So this was why Betfair and Intrade were so far apart

The big political betting this afternoon is not EdM’s speech but a report from the US about how a single trader sought to manipulate the Romney price on Intrade in the run-up to last November’s White House election.

The divergence of the two markets was something that was much discussed on PB at the time and I wondered whether such market manipulation was going on. The only problem I saw was the sheer scale of resources that would be required to do it. According to the report:

The trader bet solely on Romney and constantly sold on Obama, losing about $4 million in the process.

Those actions effectively created what the study called a “firewall” that kept prices within a defined range and made the race seem closer than it really was.“

This is always possible with political betting. People can try to use betting prices to give the impression of momentum.

Mike Smithson

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