The massive blackout beginning at about 4:00 PM Thursday, August 14th, shut down more than 100 power plants, including 22 nuclear reactors, in the United States and Canada and knocked out power to 50 million people over a 9,300-square-mile area stretching from New England to Michigan.
Power had been restored by Friday morning to sections of all five New York City boroughs and almost all of upstate New York. Early estimates had 80 percent of the state without power at the height of the blackout. Other areas also continued to have problems for more than a day.
This was the biggest blackout in history, and probably most people at first thought of terrorist attacks. Officials quickly assured us that it was a natural disaster, though they did not at first know what caused it. In any case, I decided to do an analysis, looking at a period beginning about an hour before the event and continuing for a total of five hours. The formal prediction was for all eggs in the network to respond, given the widespread media attention. I did a secondary analysis of all eggs in the Northeast, including 6 in the US and 2 in Canada. The figure below shows the formal analysis in red and the exploration in green. The formal outcome had Chisquare 17933 on 18000 df, and p = 0.637. The corresponding values for the Northeast eggs only are 18146 on 18000, and p = 0.221.