Prediction markets (also known as betting markets, information markets, decision markets, idea futures or event derivatives) are exchange-traded markets created for the purpose of trading the outcome of events. The market prices can indicate what the crowd thinks the probability of the event is. A prediction market contract trades between 0 and 100%.

The prediction interval is conventionally written as: [, +].For example, to calculate the 95% prediction interval for a normal distribution with a mean (µ) of 5 and a standard deviation (σ) of 1, then z is approximately 2.Therefore, the lower limit of the prediction interval is approximately 5 ‒ (2·1) = 3, and the upper limit is approximately 5 + (2·1) = 7, thus giving a prediction ...

Le calendrier maya était la version maya du calendrier mésoaméricain, composé de différents systèmes calendaires évoluant de manière concomitante. Il se composait d'un calendrier sacré, Tzolk'in (ou Bucxok), cyclique sur 260 jours, d'un calendrier solaire, Haab, cyclique sur 365 jours, et du compte long qui faisait le lien entre les deux précédents calendriers.