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Reock Degree Of Compactness
The Reock degree of compactness, or Reock compactness score, is a ratio that quantifies the compactness of the geographic area of a voting district. The score is sometimes used as an indication of the extent to which a voting district may be considered gerrymandered In representative democracies, gerrymandering (, originally ) is the political manipulation of electoral district boundaries with the intent to create undue advantage for a party, group, or socioeconomic class within the constituency. The m .... The Reock compactness score is computed by dividing the area of the voting district by the area of the smallest circle that would completely enclose it. Since the circle encloses the district, its area cannot be less than that of the district, and so the Reock compactness score will always be a number between zero and one (which may be expressed as a percentage). Criticism Because the Reock compactness score is defined in terms of a circle that must enclose all point ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compactness Measure Of A Shape
The compactness measure of a shape is a numerical quantity representing the degree to which a shape is compact. The meaning of "compact" here is not related to the topological notion of compact space. Properties Various compactness measures are used. However, these measures have the following in common: *They are applicable to all geometric shapes. *They are independent of scale and orientation. *They are dimensionless numbers. *They are not overly dependent on one or two extreme points in the shape. *They agree with intuitive notions of what makes a shape compact. Examples A common compactness measure is the isoperimetric quotient, the ratio of the area of the shape to the area of a circle (the most compact shape) having the same perimeter. In the plane, this is equivalent to the Polsby–Popper test. Alternatively, the shape's area could be compared to that of its bounding circle, its convex hull, or its minimum bounding box. Similarly, a comparison can be made between t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electoral District
An electoral district, also known as an election district, legislative district, voting district, constituency, riding, ward, division, or (election) precinct is a subdivision of a larger state (a country, administrative region, or other polity) created to provide its population with representation in the larger state's legislative body. That body, or the state's constitution or a body established for that purpose, determines each district's boundaries and whether each will be represented by a single member or multiple members. Generally, only voters (''constituents'') who reside within the district are permitted to vote in an election held there. District representatives may be elected by a first-past-the-post system, a proportional representative system, or another voting method. They may be selected by a direct election under universal suffrage, an indirect election, or another form of suffrage. Terminology The names for electoral districts vary across countries and, oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerrymandering
In representative democracies, gerrymandering (, originally ) is the political manipulation of electoral district boundaries with the intent to create undue advantage for a party, group, or socioeconomic class within the constituency. The manipulation may involve "cracking" (diluting the voting power of the opposing party's supporters across many districts) or "packing" (concentrating the opposing party's voting power in one district to reduce their voting power in other districts). Gerrymandering can also be used to protect incumbents. Wayne Dawkins describes it as politicians picking their voters instead of voters picking their politicians. The term ''gerrymandering'' is named after American politician Elbridge Gerry, Vice President of the United States at the time of his death, who, as governor of Massachusetts in 1812, signed a bill that created a partisan district in the Boston area that was compared to the shape of a mythological salamander. The term has negative con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polsby–Popper Test
The Polsby–Popper test is a mathematical compactness measure of a shape developed to quantify the degree of gerrymandering of political districts. The method was developed by lawyers Daniel D. Polsby and Robert Popper, though it had earlier been introduced in the field of paleontology by E.P. Cox. The formula for calculating a district's Polsby–Popper score is PP(D) = \frac , where D is the district, P(D) is the perimeter of the district, and A(D) is the area of the district. A district's Polsby–Popper score will always fall within the interval of ,1/math>, with a score of 0 indicating complete lack of compactness and a score of 1 indicating maximal compactness. Compared to other measures that use dispersion to measure gerrymandering, the Polsby–Popper test is very sensitive to both physical geography (for instance, convoluted coastal borders) and map resolution. The method was chosen by Arizona's redistricting commission in 2000.Monorief, Gary FReapportionment and Redistri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
