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Hierarchy



A hierarchy (in Greek language ''hieros'', sacred, and ''arkho'', rule) is a system of ranking and organizing things. The first usage in the Oxford English Dictionary for hierarchy is from 1380, where it was used in reference to the three orders of three angels as depicted by Pseudo-Dionysius the Areopagite. Areopagite used the word both in reference to the heavenly hierarchy and the ecclesiastical hierarchy [http://www.newadvent.org/cathen/07322c.htm]. This was the origin of the common meaning of "rule by priests". Since hierarchical churches such as the Roman Catholicism and Eastern Orthodoxy churches had tables of organization that were "hierarchical" in the modern sense of the word, the term came to refer to similar organizational methods in more general settings. == General description == Hierarchies can be generally divided into two kinds: those where the upper levels of the hierarchy are 'superior' to the lower in some way, and those where the lower levels are 'contained' in the upper, again in different ways. An example of the first kind might be a company organisational structure: the CEO is superior to the divisional managers, who are superior to their team leaders who are superior to their ordinary workers. An example of the second kind is the hierarchy of animal classification: the set of 'birds' contains the set of 'birds of prey' which contains the set of 'eagles' which contains the set of 'golden eagles'. == General description (informal) == A precise, Mathematics definition of hierarchy will be given below. This section will try to explore the ideas behind that more succinct definition. A hierarchy is a transitivity, reflexivity, asymmetry relationship, such as "is superior to", "is part of", or "is taller than": *transitivity — if ''a'' is superior to ''b'', and ''b'' is superior to ''c'', then ''a'' is superior to ''c''; *irreflexivity — no-one can be superior to herself, or taller than herself; *asymmetry — if ''a'' is superior to ''b'', then ''b'' isn't superior to ''a''. When two nodes are related, one is designated the "superior" (or sometimes the "parent") and the other the "subordinate" (or sometimes the "child"). In the intuitive case of the "is the boss of" relation, the boss is the superior and the employee is the subordinate. A hierarchy's asymmetrical relationship can link entities in one of three ways: directly, indirectly, or not at all. The illustration shows a ''direct'' link between the craft and culture sections; the craft section is directly linked to the culture section by the "contains" relationship. This is akin to how your boss is directly in charge of you. In contrast, the illustration shows an ''indirect'' link between craft and encyclopedia; the craft section is only "contained" by the encyclopedia as a whole by virtue of being "contained" by the culture section. This is akin to how the CEO of a company is in charge of a factory worker only via middle management. Finally, there is effectively ''no link'' between the art and the craft sections; neither section contains the other. This is akin to two co-workers, neither of whom is the other's boss. ''Every member is reachable from any other by following the relationship in either direction, but there is no way of coming back to a particular member by always following the relationship in the same direction.'' == Mathematical description (formal) == A hierarchy can be represented as a connected directed acyclic graph theory with a designated initial node (the ''root''). Such structures are also commonly named ''trees'' (since they look like upside-down trees, with the root at the top). == Examples of reasoning with hierarchies == Many aspects of the world are analyzed, arguably fruitfully, from a hierarchical perspective. The concept of hierarchy thus qualifies as interdisciplinarity. Science provides the following examples: * In biology, organisms are commonly described as an assembly of parts (organs) which are themselves assemblies of yet smaller parts, and so on. * In physics, the standard model decomposes bodies down to their smallest particle components. * In linguistics, words or sentences are often broken down into hierarchies of parts and wholes. * In ethics, various virtues are enumerated and sometimes organized hierarchically according to certain brands of virtue theory. In all of these examples, the asymmetric relationship is "is composed of". ==Hierarchies in programming== The concept of hierarchies plays a large part in object oriented programming. For more information see Hierarchy (object-oriented programming) and memory hierarchy. == Containment hierarchy == A containment hierarchy is a collection of strictly nested sets. Each entry in the hierarchy designates a set such that the previous entry is a strict superset, and the next entry is a strict subset. For example, all rectangles are quadrilaterals, but not all quadrilaterals are rectangles, and all squares are rectangles, but not all rectangles are squares. (See also: Taxonomy.) * In geometry: shape, polygon, quadrilateral, rectangle, Square (geometry) * In biology: animal, bird, bird of prey, eagle, golden eagle * The Chomsky hierarchy in formal languages: recursively enumerable, context-sensitive, context-free, regular * In physics: particle, elementary particle, fermion, lepton, electron == Social hierarchies == Many human organizations, such as businesses, churches, armies and political movements are structured hierarchically, at least officially; commonly superiors, called ''bosses'', have more power (sociology) than their subordinates. Thus the asymmetrical relationship might be "has power over". (Some analysts question whether power "really" works as the traditional organizational chart indicates, however.) See also chain of command. Many social criticisms include a questioning of social hierarchies seen as being unjust. Feminism, for instance, often discusses a hierarchy of gender, in which a culture sees males or masculine traits as superior to females or feminine traits. In the terms above, some feminism criticizes a hierarchy of only two nodes, "masculine" and "feminine", connected by the asymmetrical relationship "is more valuable to society", for example: :The hierarchical nature of the dualism - the systematic devaluation of females and whatever is metaphorically understood as "feminine" - is what I identify as sexism. (Nelson 1992, p. 106) Note that in this contexts and in other social criticisms, the word ''hierarchy'' usually is used as meaning ''power hierarchy'' or ''power structure.'' Feminists may not take issue with inanimate objects being organized in a hierarchical fashion, but rather with the specific asymmetrical organization of unequal value and power between men and women and, usually, other social hierarchies such as in racism and anti-gay bias. == Hierarchical nomenclatures in the arts and sciences == Hierarchies are important for categorization and organization of large numbers of objects. Taxonomy, for example, such as biological taxonomies, are built on hierarchies. Hierarchy is also often used to control complexity in engineering endeavors. For example, large electronic devices such as computers are usually composed of modules, which are themselves created out of smaller components (integrated circuits), which in turn are internally organized using hierarchical methods (e.g. using standard cells). Hierarchies are used very extensively in computer science and information theory; here are a few examples. Computer files in a file system are stored in a hierarchy of directory in most operating systems. In object-oriented programming, classes are organized hierarchically; the relationship between two related classes is called inheritance-oop. In the Internet, IP addresses are increasingly organized in a Classless inter-domain routing (so that the routing will continue to function as the Internet grows). The pitch (music) and Musical form of Tonality music are organized hierarchically, all pitches deriving their importance from their relationship to a Tonic (music) Key signature, and secondary themes in other keys are brought back to the tonic in a recapitulation of the primary theme. Susan McClary connects this specifically in the sonata-allegro form to the feminist hierarchy of gender (see above) in her book Feminine Endings, even pointing out that primary themes were often previously called "masculine" and secondary themes "feminine." Examples of hierarchies: * Theological: God, saved souls, angels, man, birds, animals, plants, rock (geology)s ** (See also Hierarchy of angels) * Scientific classification of organisms: kingdom_(biology), phylum_(biology), class_(biology), order_(biology), family_(biology), genus_(biology), species_(biology) * Social: monarch, nobles, gentry, yeomanry, peasants, serfs ==Alternatives== Hierarchies and hierarchical thinking has been criticized by many people, as above in #Social hierarchies and #Hierarchical nomenclatures in the arts and sciences. Possible alternatives include: * Enumerative organization, a list * Retiary organization, a web or network * Anarchy as a social/political theory and practice ==Specializations== * purpose: ** hierarchical organization * structural properties: ** hierarchical tree structure ** rooted hierarchy * nature of the hierarchical relationship: ** containment hierarchy ==See also== * Linnaean taxonomy * Classes (computer science) * Chomsky hierarchy * Confucianism * Maslow's hierarchy of needs * hierarchy of roads * heterarchy * holarchy * unity of command == External links == *[http://www.isss.org/hierarchy.htm Principles and annotated bibliography of hierarchy theory] *[http://www.nbi.dk/~natphil/salthe/hierarchy_th.html Summary of the Principles of Hierarchy Theory] - S.N. Salthe == References == * Julie Nelson (1992). "Gender, Metaphor and the Definition of Economics". ''Economics and Philosophy'', 8:103-125. Networks simple:Power structure

Hierarchy



This sentence... ''Every member is reachable from any other by following the relationship in either direction, but there is no way of coming back to a particular member by always following the relationship in the same direction. '' makes no sense at all to me. Does this mean that "any category node can be reached from any other category node"? If so, then this is simply wrong - that's a property of a heterarchy or a neural network. A hierarchy is defined by each descendent having a single parent node (only!) and one or more descendents (or zero descendents at the leaf node level). Any organisational structure where descendent nodes can have more than one parent is not a hierarchy, by simple definition. The wikipedia is definitely not hierarchical in its informational content, otherwise we would not have so many debates about subpages and categorisation. - User:MMGB ---- I agree; it's a very badly written sentence. I could speculate about its meaning, but I shouldn't have to. -- Mike Hardy ---- I think the one parent per node idea is too narrow to satisfy all sensible definitions of "hierarchy". This may be how it is defined in, say, Organizational Theory. But Computer Scientists speak of "inheritence hierarchies" in which a node can have multiple "parents". Actually, think about real family trees; it is arguably fruitful to view them as hierarchies, and everyone (i.e. every node) has exactly ''two'' parents. I think we should clarify, however, that ''some people'' use hierarchy for the one-parent case and heterarchy for the multi-parent case, ''if this is indeed true''. If this is true, we need to clarify what people/fields use the terminology in this manner. It certainly isn't universal. --User:Ryguasu ::I think even the initial example is confusing, with two layered ranking hierarchies and one inherited subset relationship. I dropped by because it suggested this needed some copy editing, which is my craft and avocation, but much more is needed here... That introduction needs some serious restructuring. User:Shanen 03:54, 16 Mar 2005 (UTC) ==Offensive illustration== The diagram on this page seems committed to the POV tenet that "science" is disjoint from "culture". I believe this is untenable. But I don't know how to edit the picture. Can someone essay this task? User:Michael Hardy 01:19, 9 Oct 2003 (UTC) :And it's been over a year since I posted this. No one has replaced the illustration with a better one. I've removed it. User:Michael Hardy 00:09, 23 Jan 2005 (UTC) ::I agree that the diagram wasn't perfect, but it (imperfectly) illustrated a concept in the article which had nothing to do with whether one subscribes to this perspective or not. You could have improved the diagram (while taking into account the articles which use (link to) the image); instead you just removed it, and even explicitly stated in the article that you didn't care to check whether this leads to problems with the text. This will sooner or later lead to serious pangs of conscience (subconscious or not), unless you draw for us a nice, ''inoffensive'' diagram, I can assure you. --User:Glimz 07:12, Jan 24, 2005 (UTC) :::Tell me what software to use to edit this picture and maybe I'll see if I can do something with it. User:Michael Hardy 20:10, 24 Jan 2005 (UTC) ::::Create a new :Image:Binary-tree-structure.png from scratch. I'd use xfig on Linux; for Windows — dunno actually, but any paint or diagram tool you try will be able to draw some squares and lines and most probably save as .png. Have a look at Wikipedia:Graphics_tutorials if you wish. --User:Glimz 04:37, Jan 25, 2005 (UTC) ---- See: Hierarchical organization, which I suggest should be merged with and redirected here. User:Hyacinth 07:44, 17 Jun 2004 (UTC) == Wikis == The Wikipedia community is noteworthy for being not overtly hierarchically structured, as no contributor possesses inherently higher standing than another, excepting certain limited "admin" and "developer" powers restricted to a few. However, some would counter that although there is no explicit hierarchy there are social norms which make contributions unequal, as some contributors have more influence because their edits command higher respect. Those who frequent Wikis might label Wikipedia's organization "wikiarchical". Note that the ''content'' of the Wikipedia (as opposed to the ''community'') is also organized in a fashion that is not overtly hierarchival. For the most part, the relationship between the individual articles does not form any sort of structure. :Your joking, right? How about Jimbo, the wikimedia board, the developers, beaurocrats, the arbitration commitee, the mediation commitee, Wikipedia:admins, users, new users, anons, known sockpuppets and trolls, and hard banned users.... doesn't that sound like a clear hierarchy to you? Also this ignores completely the general guideline to avoid self references when possible, on top of the POV and factual inaccuracy. 08:24, 24 Jan 2005 (UTC) ::Sorry -- I think you didn't read well. The developers, bureaucrats, admins, etc., are the ''community'', not the ''content''. User:Michael Hardy 23:03, 10 Feb 2005 (UTC) == Feminism and social criticism == I am concerned about the depiction of feminism in this article. First, it depicts feminists as sharing a single concept of the "hierarchy of gender." In fact, people who call themselves feminists have a wide range of ideas concerning gender and the power relationships related to it. Second, it implies that feminists are not interested in power hierarchies that are not based on gender. Many feminists are deeply concerned with issues of race, class, age, (dis)ability, and other sources of inequality, as well as the ways these power imbalances intersect. Also, I do not understand what is meant by "Feminists do not take issue with hierarchy in the most general definition of the word...." I think it might be best to remove the text about feminism and social criticism. I am not sure that I am up to the alternative task of writing a concise summary of the relationship of feminism to social hierarchies! User:FreplySpang 02:15, 10 Mar 2005 (UTC) :How does it look now? User:Hyacinth 02:48, 10 Mar 2005 (UTC) :: That looks pretty good. I'm glad that you found a way to clear it up without having to write a lot of new material. Thanks! User:FreplySpang 03:14, 10 Mar 2005 (UTC) == Section heading == I changed the heading back to 'general decsription (informal)' from 'mathematical...' because I wrote (most of) that section from a non-mathematical point of view. That's how 'hierarchy' is defined in philosophy and logic rather than in maths, and it applies to real-life hierarchies rather than simply to mathematical ones. User:Mel Etitis (Μελ_Ετητης)">User talk:Mel Etitis 18:20, 30 Mar 2005 (UTC)


See other meanings of words starting from letter:

H

HA | HB | HC | HD | HE | HF | HG | HI | HJ | HK | HL | HM | HN | HO | HP | HR | HS | HT | HU | HW | HX | HY | HZ |

Words begining with Hierarchy:

Hierarchy
Hierarchy
Hierarchyism
HierarchyPedia
HierarchyPedia
HierarchyPedia
Hierarchypedia
Hierarchypedia
Hierarchypedia/Sandbox
Hierarchy_(object-oriented_programming)
Hierarchy_diagram
Hierarchy_member
Hierarchy_of_Alienness
Hierarchy_of_angels
Hierarchy_of_angels
Hierarchy_of_demons
Hierarchy_of_Devils
Hierarchy_of_genres
Hierarchy_of_Hell
Hierarchy_of_human_needs
Hierarchy_of_needs
Hierarchy_of_oppression
Hierarchy_of_precious_substances
Hierarchy_of_Roads
Hierarchy_of_roads
Hierarchy_of_the_demons
Hierarchy_problem


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