Think you can win on prediction markets? Here's why you're more likely to lose

<img src='https://i.cbc.ca/ais/05065636-4e75-4420-8e6e-3a9b14714f3e,1775163697847/full/max/0/default.jpg?im=Crop%2Crect%3D%280%2C0%2C1920%2C1080%29%3BResize%3D%28620%29' alt='A billboard on the side of a building advertising a prediction market' width='620' height='349' title='An advertisement by Polymarket is displayed and predicts a victory for New York mayoral candidate Zohran Mamdani in the New York City mayoral election on Tuesday, Nov. 4, 2025, in New York. '/><p></p>