It has only been a few hours since Air India flight AI171 crashed in Ahmedabad, killing more than 260 people, yet public speculation about the causes of the disaster is already rife.

Undue and harmful public speculation won't help the families of the victims, first responders or investigators, says former ...

Railroads were built—and speculated on. Before long, New York’s young exchanges were the seats of speculation, and the bulls and bears rampaged with home-grown capital instead of European imports.