Concepts inIncentives for expressing opinions in online polls
Opinion poll
An opinion poll, sometimes simply referred to as a poll, is a survey of public opinion from a particular sample. Opinion polls are usually designed to represent the opinions of a population by conducting a series of questions and then extrapolating generalities in ratio or within confidence intervals.
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Fact
A fact (derived from the Latin factum, see below) is something that has really occurred or is actually the case. The usual test for a statement of fact is verifiability, that is whether it can be proven to correspond to experience. Standard reference works are often used to check facts. Scientific facts are verified by repeatable experiments.
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Prediction market
Prediction markets (also known as predictive markets, information markets, decision markets, idea futures, event derivatives, or virtual markets) are speculative markets created for the purpose of making predictions. The current market prices can then be interpreted as predictions of the probability of the event or the expected value of the parameter.
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Belief
Belief is the psychological state in which an individual holds a proposition or premise to be true.
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