Observational errorObservational error (or measurement error) is the difference between a measured value of a quantity and its true value. In statistics, an error is not necessarily a "mistake". Variability is an inherent part of the results of measurements and of the measurement process. Measurement errors can be divided into two components: random and systematic. Random errors are errors in measurement that lead to measurable values being inconsistent when repeated measurements of a constant attribute or quantity are taken.
Free tradeFree trade is a trade policy that does not restrict imports or exports. In government, free trade is predominantly advocated by political parties that hold economically liberal positions, while economic nationalist and left-wing political parties generally support protectionism, the opposite of free trade. Most nations are today members of the World Trade Organization multilateral trade agreements. Free trade was best exemplified by the unilateral stance of Great Britain who reduced regulations and duties on imports and exports from the mid-nineteenth century to the 1920s.
Binary systemA binary system is a system of two astronomical bodies which are close enough that their gravitational attraction causes them to orbit each other around a barycenter (also see animated examples). More restrictive definitions require that this common center of mass is not located within the interior of either object, in order to exclude the typical planet–satellite systems and planetary systems. The most common binary systems are binary stars and binary asteroid, but brown dwarfs, planets, neutron stars, black holes and galaxies can also form binaries.
Anchoring (cognitive bias)The anchoring effect is a cognitive bias whereby an individual's decisions are influenced by a particular reference point or "anchor". Both numeric and non-numeric anchoring have been reported in research. In numeric anchoring, once the value of the anchor is set, subsequent arguments, estimates, etc. made by an individual may change from what they would have otherwise been without the anchor. For example, an individual may be more likely to purchase a car if it is placed alongside a more expensive model (the anchor).
Angel investorAn angel investor (also known as a business angel, informal investor, angel funder, private investor, or seed investor) is an individual who provides capital to a business or businesses, including startups, usually in exchange for convertible debt or ownership equity. Angel investors often provide support to startups at a very early stage (when the risk of their failure is relatively high), once or in a consecutive manner, and when most investors are not prepared to back them.