Lone Candle
Champion of Truth
Pant legs getting wider started in fashion shows, but then a big and respected predictor predicted fashion would move to wider pant legs and people in the clothes industry believed in his predictions and took actions that made it a self-fulfilling prophecy.
https://www.youtube.com/watch?v=DA-CozY2isc
Prediction markets are for some reason regulated as investments, when really they are gambling. They are prone to manipulation–not just insider trading, but someone can pay a person to throw a dildo in a basketball game and then bet that someone will throw a dildo in a basketball game; someone can bet that a certain guy will get punched in the face, and then go punch that guy in the face.
https://www.youtube.com/watch?v=OXpR9bsEVqE