Bayesian Investor Blog

Politimetrics (associated with the Westminster Business School) has sponsored some additional Intrade contracts which will provide information about the impact of the presidential election on the country if they ever get enough liquidity. So far, there’s been no sign that much liquidity will exist.
One reason I (and presumably other traders) haven’t placed many orders is that the contracts deal with individual candidates. Since the value of the new contracts should fluctuate with the probability of the relevant candidate’s winning, and those fluctuations are currently much larger than any other factor affecting the prices, trading them would require any trader who doesn’t accept the market price to frequently monitor the prices of the underlying contracts. Nobody wants to do that unless the contracts already have significant volume.
Even if they had some liquidity, there’s a good deal of risk that the long-shot bias which appears to be common on Intrade would limit my confidence in the value of the information provided by those prices for all but the two or three candidates who are most likely to win in November (i.e. I’d probably believe what they said about Clinton relative to Obama, but I’d doubt they would be useful for voters in Republican primaries).
When it becomes clear who will win each party’s nomination, these problems will be reduced, and I’ll probably place a moderate number of orders on some of these contracts.
It should be possible to design a better user interface for decision markets of this nature so that users could place orders purely on the probable impact of a candidate’s election. Shock response futures come closer to doing that than contracts of the form “X wins and Y happens”, but can probably only indicate the direction of the impact.
I’ve created web pages at https://bayesianinvestor.com/amm/implied.html and https://bayesianinvestor.com/amm/implied4.html (which are currently being updated 4 times a day) which show implied prices (i.e. the price of the conditional contract as a percent of the price of the underlying candidate’s contract) that ought to represent what the markets think the probable effects would be if that candidate wins. Ideally traders could place orders expressed in terms of those implied prices, but that’s nontrivial to implement, and unlikely to happen unless someone pays Intrade a fair amount to create.
I’ve commented on Jed Christiansen’s blog about why I doubt the conditional contracts I’m subsidizing have had enough trading yet to produce valuable information. But the trends suggest there will be enough trading within a few weeks.