pro·jec·tion   (prə-jěk'shən)    n.   The act of projecting or the condition of being projected. A thing or part that extends outward beyond a prevailing line or surface: spiky projections on top of a fence; a projection of land along the coast. A plan for an anticipated course of action: "facilities [that] are vital to the projection of U.S. force . . . in the Pacific" (Alan D. Romberg). A prediction or an estimate of something in the future, based on present data or trends. The process of projecting an image onto a screen or other surface for viewing. An image so projected. The attribution of one's own attitudes, feelings, or suppositions to others: "Even trained anthropologists have been guilty of unconscious projection—of clothing the subjects of their research in theories brought with them into the field" (Alex Shoumatoff). The attribution of one's own attitudes, feelings, or desires to someone or something as a naive or unconscious defense against anxiety or guilt. Mathematics The image of a geometric figure reproduced on a line, plane, or surface. A system of intersecting lines, such as the grid of a map, on which part or all of the globe or another spherical surface is represented as a plane surface. Psychology The attribution of one's own attitudes, feelings, or suppositions to others: "Even trained anthropologists have been guilty of unconscious projection—of clothing the subjects of their research in theories brought with them into the field" (Alex Shoumatoff). The attribution of one's own attitudes, feelings, or desires to someone or something as a naive or unconscious defense against anxiety or guilt. pro·jec'tion·al adj.

Main Entry: pro·jec·tion
Pronunciation: pr&-'jek-sh&n
Function: noun
1 a : the process or technique of reproducing a spatialobject or a section of such an object upon a plane or curved surface b : a diagram or figure formed by projection;especially : VIEW
2 a : the act of referring a mental image constructed by the brain from bits of data collected by the senseorgans to the actual source of stimulation outside the body b : the attribution of one's own ideas, feelings, or attitudes to other people or to objects; especially : the externalization of blame, guilt, or responsibility as a defense against anxiety
3 : the functional correspondence and connection of parts of the cerebral cortex with parts ofthe organism projection of the retina upon the visual area>

projection pro·jec·tion (prə-jěk'shən)
n.

1. The act of projecting or the condition of being projected.

2. The attribution of one's own attitudes, feelings, or suppositions to others.

3. The attribution of one's own attitudes, feelings, or desires to someone or something as a naive or unconscious defense against anxiety or guilt.

4. The localization of visual impressions to a point in space relative to the person who is doing the viewing: straight ahead, right, left, above, or below.

5. Any of the systems of nerve fibers by which a group of nerve cells discharges its nerve impulses to one or more other cell groups.

projection theory
In domain theory, a function, f, which is (a) idempotent, i.e. f(f(x))=f(x) and (b) whose result is no more defined than its argument. E.g. F(x)=bottom or F(x)=x.
In reduction systems, a function which returns some component of its argument. E.g. head, tail, \ (x,y) . x. In a graph reduction system the function can just return a pointer to part of its argument and does not need to build any new graph.
(1997-01-29)

projection

in cartography, systematic representation on a flat surface of features of a curved surface, as that of the Earth. Such a representation presents an obvious problem but one that did not disturb ancient or medieval cartographers. Only when the voyages of exploration stimulated production of maps showing entire oceans, hemispheres, and the whole Earth did the question of projection come to the fore. Mercator produced the simplest and, for its purposes, the best solution by in effect converting the spherical Earth into a cylinder with the open ends at the poles; this cylinder was then opened to form a plane surface. East-west and north-south directions could be represented with fidelity, and the distortions in size became gross only near the polar regions (rendering Greenland, for example, disproportionately large). The Mercator projection is still widely used, especially when north-south dimensions are of chief importance. Many other projections are used, for example, the conic projection, drawn from a point directly above the North or South Pole. All projections involve some degree of distortion, and those showing the entire Earth involve a large degree

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