FiveThirtyEight

FiveThirtyEight is a website that makes forecasts about elections, sports, and other topics. It also publishes articles about those topics. It was created by statistician Nate Silver on March 7, 2008. FiveThirtyEight's name comes from the number of electors in the United States Electoral College.
FiveThirtyEight is famous for correctly predicting the winner of all 50 states in the 2012 United States presidential election. In the 2016 election, FiveThirtyEight said that Donald Trump had a 28.6% chance to win. Trump did win. However, 28.6% was much higher than other people thought, such as The New York Times and The Economist.
FiveThirtyEight has also analyzed at the calibration of their forecasts. If a forecast with good calibration says that many things each have a 40% chance of happening, then about 40% will. Their forecasts are fairly accurate.