There's a selection bias in the people who bet on elections. You only bet if you think you know something other people don't -- if you're wrong you lose your money. If you're wrong as a pundit, nothing happens. As they say, the bettors put their money where their mouth is.
There's an interesting counterargument: people who use prediction markets to hedge against the outcome they don't want. I don't know how many people actually do this, though.
There's a selection bias in the people who bet on elections. You only bet if you think you know something other people don't -- if you're wrong you lose your money. If you're wrong as a pundit, nothing happens. As they say, the bettors put their money where their mouth is.
There's an interesting counterargument: people who use prediction markets to hedge against the outcome they don't want. I don't know how many people actually do this, though.