An anonymous reader quotes a report from Wired: Prediction market boosters often tout the platforms as barometers of public opinion, or even "truth machines" offering a clearer picture of where things are headed than polling or other data. In 2024, for example, Kalshi beat many pollsters in forecasting the outcome of the US presidential race. But their trading activity can also tell more perplexing stories. Two global election markets on Polymarket's offshore platform, for instance, generated over $600 million in trading volume, far more than most political markets typically attract. Most of the activity took place buying and selling contracts tied to long-shot candidates who ultimately did not win. The report focuses on suspicious trading activity surrounding elections in Ethiopia and Romania, where researchers uncovered $284 million in questionable trades tied to Ethiopia's election and periods when 99.6% of trading volume in a Romanian election market was flagged as suspected "wash trading." According to Wired, "wash trading is a type of market manipulation in which accounts repeatedly buy and sell assets to create the illusion of heavy trading activity, when in reality, money is simply moving back and forth." Some accounts may also be artificially inflating their activity to qualify for potential cryptocurrency token rewards, a practice known as "activity farming." In response to the Ethiopian trading activity, Polymarket told Wired that the company "immediately flagged this activity, investigated, and blocked the accounts from trading." The company did not explain why the suspicious trades were allowed to continue for months before action was taken.

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