
''For Wikipedia's categorization projects, see Wikipedia:Categorization.'' ---- Categorization is the process in which ideas and objects are recognised and understood. Categorization is fundamental in decision making and in all kinds of interaction with the environment. There are, however, different ways of approaching categorization. ==The Classical View== The classical Aristotelian view that claims that categories are discrete entities characterized by a set of properties which are shared by their members. These are assumed to establish the conditions which are both necessary and sufficient to capture meaning. ==Cognitive science== Since the research by Eleanor Rosch and George Lakoff in the 1970s, categorization can also be viewed as a the process of grouping things based on prototypes - the idea of necessary and sufficient conditions is rarely if ever met in categories of naturally occurring things. It has also been suggested that categorisation based on prototypes (see Prototype (linguistics)) is the basis for human development, and that this learning theory (education) relies on learning about the world via embodiment. A cognitive approach accepts the fact that natural categories tend to be fuzzy at their boundaries and inconsistent in the status of their constituent members. Systems of categories are not objectively "out there" in the world but are rooted in people's experience. Conceptual categories are not identical for every speaker of a language. Categories form part of a hierarchical structure when applied to such subjects as taxonomy in biological classification: higher level: life-form level, middle level: generic or genus level, and lower level: the species level. These can be distinguished by certain traits that put an item in its distinctive category. But even these can be arbitrary and are subject to revision. Categories at the middle level are perceptually and conceptually the more salient. The generic level of a category tends to elicit the most responses and richest images and seems to be the psychologically basic level. Typical taxonomies in zoology for example exhibit categorisation at the embodied level, with similarities leading to formulation of "higher" categories, and differences leading to differentiation within categories. ==See also== * semantics Knowledge representation Philosophy Semantics
: ''See also: Wikipedia talk:Categorization'' For those for whom this won't be obvious, the content of this page appears to be very inspired by George Lakoff. That's not a bad thing (I like Lakoff), but it should eventually be clarified in the article, and competing views should also be included. --User:Ryguasu 02:57 Nov 25, 2002 (UTC) : I added a link to Lakoff, expanded slightly, wikified a little, and removed the Wiktionary tag. User:Spalding 13:11, Apr 3, 2005 (UTC) == Perceptual categorization? == We should formulate an amendment to this entry to consist of information detailing the science of perceptual categorization. That is, the way people determine an individual or group's thematic status (e.g., reformer, deathbringer, atheist, Christian, scientist). Of course, this topic may be covered elsewhere. If so, then we should amend the article to disambiguate. User:Adraeus 14:35, 10 Dec 2004 (UTC)
This article provides guidelines on creating and organizing categories. For a quick introduction to categories, see Wikipedia:Category. For everything you ever wanted to know about categories, see Wikipedia:Categorisation FAQ. ==When to use categories== Every page in the article namespace should have at least one category. Categories should be on major topics that are likely to be useful to someone reading the article. :Article: Michael Jackson :Useful category: :Category:Pop singers :Not useful: ''Category:Musicians whose first name starts with M'' Questions to ask to know if a category is the appropriate tool: *Is it possible to write a few paragraphs or more on the subject of a category, explaining it? *If you go to the article from the category, will it be obvious why it's there? Is the category subject prominently discussed in the article? If the answer to either of these questions is no, then a category is probably inappropriate. An article will often be in several categories. Restraint should be used, however — categories become less effective the more there are on a given article. An article should not be in both a category and its subcategory, for example Microsoft Office is in :Category:Microsoft software, so should not also be in :Category:Software. An article with the same name as a category should usually belong only to that category, for instance, Deism belongs only in :Category:Deism. Categories appear without annotations, so be careful of NPOV when creating or filling categories. Unless it is self-evident and uncontroversial that something belongs in a category, it should not be put into a category. Exceptions to the above rules are categories such as :Category:Stub categories which are intended to aid the function of Wikipedia editing. For alternative methods of grouping articles, and the circumstances in which they should be used, see Wikipedia:Categories, lists, and series boxes. === Categories vs. Lists vs. Info boxes === See: Wikipedia:Categories, lists, and series boxes === Categories applied to articles on people === A separate wikipedia page Wikipedia:Categorization of people was created to help you in designing, applying and checking categories that are used for articles on people. ==Categories do not form a tree== Each Wikipedia article can appear in more than one category, and each category can appear in more than one parent category. Multiple categorization schemes co-exist simultaneously. In other words, categories do not form a strict hierarchy or tree structure, but a more general directed acyclic graph (or close to it, see below). Nevertheless, parts of the category graph will be tree-like, and it may be convenient to think of parts of the category graph as being like multiple overlapping trees. ==Cycles should usually be avoided== Although the MediaWiki software does not prevent cycle (graph theory) (loops), these should usually be avoided. ==Guidelines for assignment of categories== ===How to create categories=== Creating a category is as simple as adding a soft link to the appropriate article in the Category: namespace; for instance, to add Felis silvestris catus to the "fluffy creatures" category, you would edit the article and enterFluffy creatures at the bottom, but ''before'' Wikipedia:Interlanguage links. Although the link will not appear in the article text, a page called Category:Fluffy creatures will automatically list alphabetically all articles that contain the Fluffy creatures link. The appeal of categories is that unlike lists, they update themselves automatically, and that one can use them to quickly find related articles. However, categories are not a substitute for Wikipedia:lists, and you will find that many articles belong to both lists and categories. You may see some inconsistencies when first creating the category - it may alternate between appearing empty and appearing with your first additions. It will probably correct itself in a few minutes.
Note that, although "uncreated" categories ''will'' correctly list articles that have been assigned to them, the category page itself does not exist until it is manually created. The easiest way to create the category page is to follow the edit link from an article and add a parent category and a category description as explained below.
===Creating subcategories===
Create subcategory pages by putting the name of the parent category on a category page that you would like to be the subcategory. Child categories (subcategories) are created by putting Flowers , Roses becomes a subcategory of Flowers.
When adding an article to a category, or creating categories, one should be careful to use the correct categories and subcategories. Horizontal categorization, directly below, refers to placing an article in the correct category while vertical categorization refers to placing an article in the correct ''sub''category.
When assigning an article into categories, try to be thorough in a
"horizontal" sense. The topic may be associated with a geographic
area, a historical period, an academic subfield, a certain type of
thing (like a food or an ornament), and/or a special interest topic
(like Roman Empire or LBGT). You might need to poke around the
category hierarchy a bit to find the right place. Try searching for
articles similar to the article you are categorizing to get ideas or
to find the most appropriate place. (For instance, '1990' is more correctly in 'Category:Years' rather than 'Category:Places'.)
In the "vertical" dimension, you should probably be more frugal. A
good general rule is that articles should be placed in the most
specific categories they reasonably fit in. For example,
Elizabeth_II_of_the_United_Kingdom should not be
listed directly under People, but Queens of England might be a good
place for her. We know that all Queens of England qualify as Famous
Britons and as Royalty, and all of those folks qualify as People. But
sometimes there's a good reason to assign an article to two
categories, one of which is a direct or indirect subcategory of
another. For a well-argued case study, see John Lennon.
Whatever categories you add, make sure they do not implicitly violate
the neutral point of view policy. If the nature of something is in
dispute (like whether or not it's fictional or scientific or whatever),
you may want to avoid labelling it or mark the categorization as
disputed. Most categorizations are pretty straightforward, though.
===Making groups of subcategories===
Categories can only list 200 entries at a time. When there are more than 200 entries, only the first 200 will be displayed. To make it easy to navigate, add a TOC (table of contents). TOCs are added by typing:
:'':Category:Automotive technologies appears as :Category:Automotive technologies.
===Redirected categories===
Although it is possible to attempt to redirect categories by adding a line such as #REDIRECT :Category:Automotive technologies to a category, it is not generally recommended because of limitations in the mediawiki software. Categories "redirected" in this way do not prevent the addition of articles to the redirected category. Articles added to the "redirected" category do not show up as in the target category.
Until these issues are addressed (in future versions of the software), #REDIRECT should not be added to category pages.
===Category sorting===
Contrary to some expectations, text after a pipe ("|") in a category link is not used in place of the category text. Rather, this text is used as the sort key on the category page itself. However, again contrary to expectations, that sort text is not displayed.
For example, the :Category:Three-digit Interstate Highways uses this property to sort secondary interstates by their primary. That is, the category link in the article for Interstate 190 (Illinois) is Three-digit Interstate Highways . This causes "Interstate 190 (Illinois)" to be listed right after "Interstate 189" and right before "Interstate 290 (Massachusetts)" under the heading "9" in the category page.
This feature is very useful for categories in which:
* the entries are people, in which case sorting by last name is preferable (example: :Category:Presidents of the U.S.).
* variations in the naming of entries causes inconsistent sorting (example: List of counties in Nebraska, List of counties in Montana, but List of Nevada counties in :Category:Lists of U.S. counties).
* the logical sort order is not alphabetical (example: individual month articles in year categories such as :Category:2004, using e.g. the sort key "*2004-04" for April).
Using this method to sort category entries is sometimes informally referred to as ''the pipe trick''. However, this use of the pipe character is very different from the original Wikimedia m:Help:Piped link#Automatic conversion of the wikitext (pipe trick) which allows one to easily hide parenthetical disambiguation in links.
It is possible to force an article or subcategory to the top of the list by using a non-alphanumeric character as the first after the pipe. For example, using Ford (note the space) or Ford would force that article to be displayed before all the others. However, note that Wikipedia_talk:Categorization/Archive_6#Using_sort_keys_to_sort_certain_articles_at_the_top.3F.
===Year categories===
In categories which are years, such as :Category:2004, special sorting guidelines apply:
* Entries should generally be sorted by ''topic'', so the article 2004 in film, for example, would contain the category reference 2004 while 2004 Canadian budget would contain the reference 2004 ; List of religious leaders in 2004 would contain 2004 .
* The article about the year itself, 2004, should be sorted first among all articles by using 2004 .
* Articles for individual months, such as October 2004, should be sorted ''chronologically'' in the first section on the category page, in this case using 2004 .
===Interlanguage links to categories===
Interlanguage links work just as they do for regular articles;
*Old talk at Wikipedia talk:Categorization/Archive 1 *Archived main page discussion on Hierarchicalization at Wikipedia talk:Categorization/Archive 2 *Further discussion at Wikipedia talk:Categorization/Archive 3 *Further discussion at Wikipedia talk:Categorization/Archive 4 (archived on 4 September 2004, includes material up to approximately 20 Aug 2004) *Further discussion at Wikipedia talk:Categorization/Archive 5 Includes material up till about 8 September 2004 *Further discussion at Wikipedia talk:Categorization/Archive 6 Includes material up till about 30 September 2004 *Further discussion at Wikipedia talk:Categorization/Archive 7 Includes material up till about 22 January 2005 ==Category - Images "OF" People should not mean "WITH" people, should it? == Are too many images merely with a person somewhere in the picture being included in the category "images OF people"? User:Wikityke 22:15, 4 Feb 2005 (UTC) Discussion at Category_talk:Images_of_people == Super Categories == This category/supcategory thing needs some rethinking. As I see it, the general rule that "if something is in a subcategory, it shouldn't also be in the supercategory" often does not make sense. Sometimes the subcategories mark clear distinctions between things, but sometimes the subcategories are just unimportant attributes imposed on the category. I'll give you some examples that make sense: :Category:Musical theatre has two subcategories; :Category:Operettas and :Category:Musicals, both of which have all the articles about individual works of Musical theatre. This makes sense because: * There is very little overlap between Operattas and Musicals, they are almost distinct categories * Most people looking for a list of works would find this distinction helpful. * The distinction that makes the subcategory is intrinsic to the category, not just a randomly chosen attribute. For instance, the works could be in subcategories that intead of using Operetta and Musicals could have used the year they were composed. This would not be very helpful for someone looking for a list of musicals. :Category:Musicals has the subcategory :Category:Musical films. This is a trickier situation. Some of the articles in Musicals are in both categories. For some titles there are seperate articles for both the movies and the theatre productions. This makes sense because: * If Wikipedia were complete there would be seperate articles for both * The films almost always come after the theatre productions An argument could be made for making Musical Films a subcategory of Musical Theatre instead of Musicals but it doesn't really matter. Some categories do not work so neatly. An example which is really bothersome is :Category:Film directors which has the subcategory :Category:Film directors by nationality which has 28 subcategories. It does not make sense to have each director only listed in a subcategory by nationality. The nationality of the director is interesting, but not all that important. Some directors start in one country and move to another. I have no problem with there being categories for directors by nationality, but I think ALL of them should also be in the directors category. The reason for this is: * Having them in both categories makes it easier to find a director if you know his nationality, and MUCH easier if you don't know his nationality. Which brings me to :Category:Bridges in New York City. This category has the subcategory :Category:Toll bridges in New York City. Whether a bridge has a toll or not is not all that important, and the attribute does not instruct the reader to notice something important about bridges. If you want to see the articles about the bridges in New York City, why should you have to look in two places? The notion that articles should not be listed in categories and subcategories strikes me as an artifact left over from libraries. The beauty of hypertext is that things can be linked many ways, not just organized on shelves. Why can't things be in multiple categories? I'd like to see ALL the bridges in New York State listed in :Category:Bridges in New York. This makes it easy to see a list of all the bridges in a geographical region, and also the subregion. I made the change for all the bridges in New York City. But within a day they were all reverted. I'd like to do it for bridges the rest of the world, film directors and some other categories, but I know I need the consensus of everyone else. I've read most of the discussion relevant above, and I don't see a good argument for keeping things the way they are. The important thing is to make Wikipedia USEFULL. User:SamuelWantman :Yes, I quite agree. I made a similar point when User:SPUI moved Indiana Toll Road and Ohio Turnpike from :Category:Transportation in Indiana and :Category:Transportation in Ohio into :Category:Toll roads in Indiana and :Category:Toll roads in Ohio. I objected that both roads are very prominent fixtures of the transportation systems in both states, and are, as far as I know having lived in both states for many years, the only toll roads in either state. While it is quite possible that there may indeed be some other toll roads in those states, those have nowhere near the recognition of the ones mentioned above. It makes no sense to me to place these roads into what are currently (and as far as I can tell, for the forseeable future) single-item subcategories. I don't really see the point of the toll road sub-categories in these states where toll roads are relatively uncommon, if not singular entities. But while I'm willing to leave these subcategories be, it seems ridiculous to me to only categorize such prominent features of the transportation systems of those states in minor subcategories. I might note that many of the other by-state subcategories under :Category:Toll roads in the United States are also single-item categories--though since I'm not familiar with those states I can't really say anything about the relative prominence of the roads in those states. User:Bkonrad≠User talk:Bkonrad 02:31, Jan 31, 2005 (UTC) ::Actually, the Ohio Turnpike is really only relevant if you live in northern Ohio, but I see your point. I think the point of putting it in its own subcategory is to make navigation via :Category:Toll roads in the United States more consistent. However, there is no clear policy on whether it makes any sense to have one-member categories for navigational purposes. (Though the current trend is to say that yes, it does. See :Category:Albums by artist.) Anyway, with the toll roads, I would just about go as far as saying that there is little point in having individual state subcategories; there aren't ''that'' many toll roads. ::For film directors, it is against current policy to put them in both a specific nationality category ''and'' the parent :Category:Film directors. All members of subcategories are supposed to be considered members of the supercategory. The current wiki software doesn't allow that, but that doesn't make it any more useful to throw all the film directors into one unorganized mess. (Also, huge supercategories make it harder to ''find'' the subcategories with the current system. If there are more than 200 members, you start having to go through pages to find the children categories.) Ideally, of course, we could put an article in :Category:Film directors and a nationality category and look up the intersection of the two, but at the moment that isn't possible. ::(Note: If you know the name of the director, you're not going to be looking up the article via categories, anyway. Huge categories are not helpful to casual browsers.) :::Category:Musical films is a special case. (There ''are'' actually musical films that were not ever stage musicals. See for instance ''Moulin Rouge!''.) Ideally, we would come up with some term for musicals that appear on stage and make that a sibling. -User:Aranel ("Sarah") 03:07, 31 Jan 2005 (UTC) I agree with Samuel that the category/subcategory thing is a problem. I've been thinking about it for a while, and here's what I decided: The reason for the difficulty with :Category:Film directors vs. :Category:Film directors by nationality is that :Category:Film directors by nationality is fundamentally flawed. We shouldn't have subcats for "randomly chosen attributes", as Samuel put it. Instead, have * :Category:People by occupation with :Category:Film directors as a subcat * :Category:People by nationality with country subcats and other random things like * :Category:People by height with a subcat for each, say, centimeter * :Category:People by handedness with left and right subcats etc. Then we need a software feature that allows a page to represent the intersection of some categories. So, for example, if I decide I want to see all left-handed Hungarian film directors, I can just request the intersection of :Category:Left-handed people, :Category:Film directors, and :Category:Hungarian people. I don't have to explicitly put people into :Category:Left-handed Hungarian film directors, as now. Under this scheme, it would be possible to categorize a person with all their attributes (height, handedness, occupation, etc.) without having to worry about explicitly making intersection categories. The category organization would become flatter, with many current subcats replaced by the new software feature. I think this proposal would neatly solve the problem that Samuel described above. User:Dbenbenn | User talk:Dbenbenn 04:13, 31 Jan 2005 (UTC) Another example: the proposed intersection feature would allow you to find people who were born in 1850 and died in 1950 as the intersection of :Category:1850 births with :Category:1950 deaths. As it is now, you'd need a :Category:1850 births, 1950 deaths, which would just be silly. User:Dbenbenn | User talk:Dbenbenn 04:29, 31 Jan 2005 (UTC) : That's quite a good idea. I wonder if it's feasible performance-wise. The other problem I forsee is there's no obvious user interface. – 04:19, Jan 31, 2005 (UTC) :: Thank you :). I haven't really thought about how the user interface would work yet. You would definitely want to be able to link to the intersection of two categories. One possibility: you could, for example, simply make a page :IntersectionCategory:Left-handed Hungarian film directors with the content :::#intersection :Category:Left-handed people :Category:Hungarian people :Category:Film directors
:: User:Dbenbenn | User talk:Dbenbenn 04:29, 31 Jan 2005 (UTC)
:: I don't think performance should be an issue. Getting the intersection of three categories is simply a matter of getting the members of the three categories, and seeing which articles are in all three. User:Dbenbenn | User talk:Dbenbenn 05:34, 31 Jan 2005 (UTC)
I agree that the whole category/subcategory criterion as it is now formulated is seriously flawed. From previous discussions, I have concluded that the rational for the "no listing in both a category and also in a sub/super category rule" goes something like this. "We want to impose order in our data base system. If we don't the resulting chaos will make the system unworkable." But this is nothing more than fear mongering based on faulty reasoning and a psychological predisposition for structure. Infact, abandoning the "not in adjacent categories rule" will make the system more user friendly. The criterion we use in deciding what categories articles should be placed in should be user driven. We should ask ourself in which categories the user would expect to see an article listed. We cannot forget that the purpose of the category system is to make it easy for users to find articles, not to create an elegant database free from duplications or overlaps. By abandoning such rules of structure we will create a database that matches the real world and the expectations of real people. Rather than forcing reality to fit into our preconceived notion of what an ideal database structure looks like by using such rules, we should let reality shape the structure of the database. Some specific examples will illustrate. I started to append category tags to the business articles. Of the 1600 business articles about 700 would go in the business category and between 300 - 100 in each of the 20 main subcategories. Obviously there was overlap. This is beceause an article like income statement, for example, while it is primarily an accounting and finance term, is also a general business term. It is used by marketers and other business people as part of their discipline, not in an accounting context. It is a general business term applicable to all of business and as such belongs both in the accounting category and the business category. Since I started working on the Business category, most of the edits have been reversed, by those claiming that an article cannot be in both a category and a subcategory. I am certaining not going to waste any more time working on such a dysfunctional system. The "no listing in both a category and also in a sub/super category rule" is not the only structural criterion that plagues the category system. There is also the "Too much overlap rule". The International trade category is currently listed for deletion and the reason given is that there is too much overlap with the International economics category. Well, news flash . . . in the real world there is conciderable overlap between the two subjects. There is also the "categories must be structured only along one dimension rule". I discovered this one in regards to the busiess law category that someone wanted to deleate. The rational given is that the other law subcategories are structured on theortical grounds rather than practical ones. On this argument, practicle subtopics like business law, maritine law, and real estate law should not have their own categories because it would be out of step with the system of legal subcategories based on legal theory. I say stamp out all of these structural criteria and let there be only one criteria, a user driven one. (If, for some reason, you want to hear more, the section "Inconsistant criteria" earlier on this page has more of my rantings on this topic) User:Mydogategodshat 17:23, 31 Jan 2005 (UTC)
:I completely agree with user:mydogategodshat. User:Zocky 17:59, 31 Jan 2005 (UTC)
So can you provide examples of articles that, in your opinion, would belong in a category but ''not'' in its supercategory? -- User:Jmabel | User talk:Jmabel 18:07, Jan 31, 2005 (UTC)
:There are many examples of articles that are specific in nature and therefore only belong in a subcategory. There are also many examples of articles that are general in nature and therefore only belong in a supercategory. But this is irrelevant. The question is whether there are articles that are both general and specific, and therefore belong in both a category and a subcategy. The answer is yes. Income statement mentioned above is an example. There are many more. Take the focus group article. In a business context, a focus group is primarily a marketing term and belongs in the marketing category. However, the focus group technique is used in virtualy all of business. It belongs in the business category as well. The real world tells us to put the article in both tha marketing and business category. Wikirules tell us to decide which one to put it in because we are not allowed to put it in both. User:Mydogategodshat 18:52, 31 Jan 2005 (UTC)
I too would love to have a properly normalized database structure for categorizing wikipedia, but the current software simply isn't meant for that. For that we would need something like People . But that just raises additional questions (what when categories overlap? how to produce a good UI for that? would we need to invent or implement a query language?
But categorization also has another important function, that of providing a table of contents, and that is completely achievable with the current system. The user should find articles easily through categories, without having to go deeper than necessary. Ideally, a category should include all articles that fall into it. If there are too many theoretical members of a category (as is usually true for supercategories), it should list the most notable and representative members. Imagine a two-frame UI where you can browse categories on the left and view articles on the right and you may see what I mean.
Here are several examples (some with non-existent categories):
*Kingston upon Hull should be in :category:English cities and :category:British cities, but not in :category:European cities or :category:World cities. London should be in all of them.
*Falklands war should probably be in :category:History of the 20th century but not in :category:History. World War II should be in both.
*OpenBSD should be in :category:Unix, but not in :category:Operating systems. Linux should be in both.
User:Zocky 19:15, 31 Jan 2005 (UTC)
This looks to me like a recipe for diverting massive effort from writing, or even usefully categorizing, articles into endless disputes about how broad is the importance of a particular article (or its subject). I can imagine bunches of people trying to promote (or demote) the importance of particular colleges and universities, moderately sized towns, people from particular countries. -- User:Jmabel | User talk:Jmabel 19:54, Jan 31, 2005 (UTC)
: I definitely agree. I can see someone going through and putting every minor war into :Category:History, then someone have to go back and revert every article and explain things. With a community project like this, it's much easier to have black-and-white rules rather than gray rules. Importance is so subjective, it'd be very difficult for something like this to converge, much more so than a regular article. – 20:00, Jan 31, 2005 (UTC)
:: If you look over this page you can't help but notice that the CURRENT situation is "diverting massive effort from writing, or even usefully categorizing, articles into endless disputes about how broad is the importance of a particular article (or its subject)." With the current rules most of the categories make sense, but some of them don't. I think the important rule should be "Categories should be organized to make it easy to browse through related articles". This rule can be applied to every category. In some categories the "no sub/super category duplication" rule will make the categorys more useful. But sometimes it will make sense to break the rule. Take the example of bridges. There is a hierachy under :Category:Toll bridges in the United States. Down that hierarcy it makes sense to keep the entries for :Category:Toll bridges in New York City from also being in the Supercategories. But there is also a hirearchy under :Category:Bridges in the United States. Putting the toll bridge categories as subcategories is really just putting a related category as a subcategory because that subcategy is already part of a different hierarchy. Because of this, it would make sense for ALL the bridges to be listed in :Category:Bridges in New York City, and have some entries duplicated in :Category:Toll bridges in New York City. These decisions could happen in the talk pages of the categories whenever consistancy gets in the way of useability. User:SamuelWantman 04:22, 5 Feb 2005 (UTC)
Lots of good reasons to change the rules. I was skeptical about the value of categories when they first appeared. But I have found them to be a great way to BROWSE through wikipedia. If I find an interesting page, I check the categories to find other interesting related pages. This is one reason why I am frustrated with the current system. When I want to browse through the articles on film directors, I don't want to have to look at 28 different categories! Likewise, If I'm looking to see what articles might be missing about film directors, how will I know if something is missing if I have to browse through numerous categories. One comment was that the directors category would be much too long if all the film directors were in it. To this I say, that it is easier to browse through 2 or 3 lists broken alphabetically, than combine 28 lists in my head. With the current system, if I want to browse through just French film directors, I can. But, if I want to browse through ALL the directors, I can't. Why not both?
There is also a bigger philosophical issue here. By having the current rules, it forces people into making categories based on a single "world view" of what is important, and how things should be organized. That world view comes from the first people who set up the categories, and then everyone else is forced to accept that world view or have their work reverted. This is what happened to me when I found :Category:Bridges in New York City arbitrarily divided between "Toll bridges" and "Toll free bridges". But who is to say that that is important? Perhaps I think that it is NOT important. I can't change it because the world view is set. What we should encourage is MULTIPLE world views. This would make Wikipedia MORE interesting, MORE usable, and (perhaps best of all), get rid of countless discussions about what the PROPER category distinctions are. User:SamuelWantman 20:14, 31 Jan 2005 (UTC)
:The current system ''does'' allow multiple world views. If instead of dividing New York's bridges based on toll/non-toll you want to divide them based on whether they've got rail roads on them or not, create two new subcategories for Bridges of New York City called "Rail bridges of New York City" and "Rail-free bridges of New York City" and go nuts categorizing the various bridges into them. The toll categories will still exist, and now the rail categories will too. Articles can belong to both of them. User:Bryan Derksen 08:47, 1 Feb 2005 (UTC)
::But look at my concrete example about :Category:Bridges in New York City. I think that all the bridges in New York City should be in this category, but they are not. Some of the bridges are in a subcategory:Category:Toll bridges in New York City. I put the toll bridges in BOTH categories, and my changes were reverted. I am forced to the world view of toll bridges and non-toll bridges. What is wrong with having the toll bridges in both places? I don't think we should get rid of :category:Toll bridges in New York City, and there is no way under the current rules for me to add those bridges to :category:Bridges in New York City. So I'm stuck with a world view I don't like. User:SamuelWantman 03:44, 5 Feb 2005 (UTC)
"But this is nothing more than fear mongering based on faulty reasoning and a psychological predisposition for structure." This was said about by User:mydogategodshat. It's untrue, and also very offensive, intentionally or otherwise. It is perfectly fair and valid to say that ''enormous'' categories are not at all useful to browsers. Take a look at :Category:Stub. Just to ''figure out what subcategories there are'' you have to search through every page of the category. (Actually, there aren't any subcategories in that particular case.) This is not helpful to the casual browser. When I look for articles about film directors, I don't want to have to flip through 20 different pages of unorganized articles any more than someone else wants to look at 20 subcategories.
There are categories that contain ''thousands'' of articles. These categories are not particularly useful to ''anyone'' at the moment because they are so enormous that you can't reasonably page through them.
The current software ''does not permit us'' to view the intersection fo two categories. This has been proposed numerous times and would be a great idea, but we can't always function under the assumption that a feature ''might'' exist in the future. We can't pull up "all members of the film directors category who are also in the American people category", so "American film directors" is a useful distinction to make. Get some developers to look at the feasibility of this (and to agree to work on this) before trying to use the current system to do something it can't do. -User:Aranel ("Sarah") 23:36, 31 Jan 2005 (UTC)
:The fear mongering continues with talk about "enormous categories". If categories get too large subcategories should be created and some of the articles placed in the new subcategory. Please don't try to use the enormous category argument to try to convince us that those article that belong in both a category and a subcategory must be forced into one or the other. It dosn't wash. User:Mydogategodshat 00:45, 1 Feb 2005 (UTC)
::Probably you didn't intend to do so, but I would appreciate it if you didn't question my motives. (But seriously, why would anyone be ''afraid'' of "enormous categories"? I don't imagine anyone has ever had a nightmare about being stuck in a huge category, or being chased by a monster category...I'll let you know if I have one tonight.) I'm trying to think practically here.
::I don't see the difference between what you propose and the current system. :Category:Film directors gets to big, so we divide it into subcategories by nationality (or whatever). The musical theater example above is a good example of a case when the sub- and super-categories convey different shades of meanign and therefore both should be used. However, something like :Category:French film directors is not as ambiguous. A person who is a French film director is ''obvious'' both a French person and a film director. I don't see that such an article would need to be in the parent category as well as the specific category. -User:Aranel ("Sarah") 04:53, 5 Feb 2005 (UTC)
:::The difference is that in the current system, if you put an article in both a category and a subcategory someone will delete it from one of them because we are not allowed to have an article on two adjacent levels. I have had scores of edits reversed for this reason. As for your question "why would anybody be afraid of enormous categories", the answer according to contributors earlier on this page, is that they make the category system difficult to use. The people that use this arguement want us to believe that allowing an article in two adjacent levels will somehow make the system unworkable. User:Mydogategodshat 03:27, 7 Feb 2005 (UTC)
As people describe their vision of category 'intersections', I think they really mean they would like a keyword type of system rather than the bucket category system like we have now. I did a lot of categorizing after I started here, but eventually gave it up because it felt like I was in quicksand. The more I worked with the current category system, the more I came to dislike it.
In a keyword system, a list of keys could be assigned to an article, and each category would also be assigned a set of keys. For example, back to the film directors, an article could be assigned the keys 'film director' and 'from Germany' (as well as any number of other keys). When the category :Category:German film directors is created, it may be assigned only the keys 'film director' and 'from Germany', and only articles containing both of those keys would be listed in that category. One might then ask, Why bother creating categories in that type of system? Because we may want the capability to describe what is being listed with that particular key combination, and also to link categories together in a structure that would be conducive to browsing. —User:Moverton 04:25, Feb 1, 2005 (UTC)
Seems to me that a lot of this is less about ''categorizing'' than about ''viewing'' the categorized information. People could get what they needed if there were an easier way to show a few layers of the category hierarchy at once. -- 07:02, Feb 1, 2005 (UTC)
:I suspect that a keyword search would be just as problematic as the current search, which is almost always disabled. (Although perhaps not quite as bad. There wouldn't be as much text to search, but there would be just as many articles. I don't know how the search is implemented.) -User:Aranel ("Sarah") 04:53, 5 Feb 2005 (UTC)
Wikipedia already has several categories in which articles are entered in both Supercategories and Subcategories. This happens when an article is entered into the bottom level of two category hierarchies and one hierarchy happens to be a subset of the other (like Bridges and Toll-bridges which I talked about before). For example, :Category:Best Actor Oscar is a subset of :Category:Cinema actors. Jack Nicholson is in both categories as he should be! Do people really believe that all the Oscar winners should be removed from :Category:Cinema actors, this would make the category much, much less usefull for browsing. Can we at least amend the rules to say that Categories can be in sub and supercategories when they are at the bottom of two hierarchies and one hierarchy is a subset of the other? -- User:SamuelWantman 07:49, 8 Feb 2005 (UTC)
:Does that really make much sense, Samuel? I think that if Nicholson is in a ''subset'' of :Category:Cinema actors, then he cannot belong to :Category:Cinema actors itself. If we were to allow that, then who's to say where to draw the line? Then people would argue that Nicholson equally deserves to be part of :Category:Actors. As well as :Category:Entertainers. And why not :Category:People!
:In my mind, the logical way to rephrase your rule would be: ''Articles can belong to several categories when they are at the bottom of two hierarchies and one hierarchy is not a subset of the other.''
: --User:Verdlanco User_talk:Verdlanco 09:19, 8 Feb 2005 (UTC)
::Yes, Verdlanco, it really makes alot of sense! People can make this decision based on what makes a category useful, and it is not useful to remove things from categories just because there happens to be another hierarchy that has a smaller subset of articles. Sometimes it would be a really, really bad thing to do. For example, I just came across :Category:African-American actors which is a subcategory of :Category:American actors. Thankfully, all the actors are on both lists. According to "the rules" they shouldn't be. Are you an advocate of apartheid? -- User:SamuelWantman 09:35, 8 Feb 2005 (UTC)
:No, I just feel that if an article fits equally well in a category ''and'' its sub-category, that is a sign that it was a bad idea to create that sub-category. (And that's double true for your apartheid analogy.) Therefore, I think the rule is good the way it is, and that avoiding duplicate category entries will eliminate more dilemmas than it causes. But that's just my opinion.
: --User:Verdlanco User_talk:Verdlanco 19:13, 8 Feb 2005 (UTC)
This is copied from my talk page (with Rick Block's permission):
::::User:SamuelWantman 08:09, 9 Feb 2005 (UTC)
::...I'm getting to the point where I've pretty much had it with categories (too many folks unwilling to budge from absolute positions, particularly the notion that category membership must mean "is a"). I posted some comments last December (see Wikipedia talk:Categorization#Categories vs keywords), which elicited zero response. IMO categories are fundamentally ambiguous and mean both your "related cat" concept as well as the hierarchical "is a" relationship many people seem to insist they are (well, should be). I don't think there will be any category-related software changes any time soon, so this seems like a relatively pointless discussion (the current reality being that category membership has no intrinsic meaning, formal or otherwise, so trying to impose one is doomed to failure). I've spent a fair amount of time categorizing (maybe 3000 edits worth), and I'm starting to think it's basically a waste of time. I suppose it's more worthwhile than playing minesweeper, but in what universe is it reasonable to argue about whether "list of " should or shouldn't be in "category: "? -- User:Rick Block 02:33, 8 Feb 2005 (UTC)
=== Proposed Guidelines ===
I have run into this issue a few times in my very short stay (so far) on Wikipedia and did some thinking about the situations where I think an article should be in a category as well as a sub-category. I came up with two guidelines and wanted to see if other people had similar ideas or if I am smoking crack. This seems to be the best place to get opinions on this issue so here I go ....
==== Qualitative vs. Quantitative ====
If the articles in a category are fundamentally the same type of article (i.e. about people or places etc.) and the difference between the category and sub-category is fundamentally qualitative then the article should only be listed in the sub-category. This is the example from the main page: ''Queen Elizabeth should not be listed directly under People, but Queens of England might be a good place for her.'' To say it a different way Queen Elizabeth would not be put "Queens of England" just because she was a better/more famous/more notable person.
The other side of this is when the difference is primarily quantitative. The example than I ran into that is good here, is the category "Chess grandmasters" and "Chess players". A person DOES go from being 'just' a chess player to being a Chess grandmaster by being a better chess player, so the difference is primarily quantitative and the article should be listed in both. A good way to tell if you are in this situation is: If the sub-category were deleted and all its contents imported into the super-category would it significantly reduce the usefulness of the super category? This brings me to the second guideline.
==== Navigational utility ====
In the above example the category "Chess players" could be further subdivided so that there were categories for "Chess International Master", "Chess Masters" etc. so that no people articles are in the super-category. In that case you would not want to include individual articles in both categories. But would this be useful? Categories are fundamentally a navigation aid. What is going to help the user looking for an article by navigating the Category tree (graph) find what they need? Does a specific categorization make it harder or easier for them to find what they are looking for?
My example here is also from chess. Category "Chess" is currently in the following three categories: "Chaturanga game family", "Mental-skill games", and "Board games". Based on the rule of not listing an article in a category and a sub-category "Mental-skill games" and "Board games" should be removed since "Chaturanga game family" is already in both of these categories. But, how many end users have ever heard of the Chaturanga family of games? I play chess a lot and I did not know this bit of information. This is the kind of Category that is useful moving up the category hierarchy rather than down. Chess should be in "Board games" and "Mental skill games" because that is where users will look for it when trying to find it. Equally it should be in "Chaturanga game family" because users might learn that and then after they are done reading about chess use the link into the category to learn more about related games.
Summary: I hope this is the right place for this, and as a clueless newbie I hope I am not re-hashing something that has already been discussed into the ground and resolved. If so and there has been some succinct treatment of the issue somewhere a pointer on my talk page would be awesome, even though I put "Proposed guidelines" above I am really just asking since I keep running into this and I am a but of a metadata freak. User:Dalf | User talk:Dalf 02:18, 21 Apr 2005 (UTC)
:To anyone who has read this thread to this point, please read the other related entries on this page. Also, note that there is a proposed comromise to this issue further below. -- User:SamuelWantman 00:23, 10 May 2005 (UTC)
== Category pages should sort by namespace first ==
Category pages should sort by namespace first. It would make things a lot easier. For example, a lot of templates have categories attached to them. Those templates shouldn't be under "T", but there's no way to pipe them without screwing up the articles that use the template. Main namespace should be listed as-is, then after that section there should be other alphebetized sections for other namespaces. – 19:05, Jan 31, 2005 (UTC)
:Actually I think it would be better if we had a method of making the templates disappear from the categories since the template itself really isn't supposed to be grouped with the articles in the category. —User:Moverton 04:30, Feb 1, 2005 (UTC)
== Categories and/or Classification ==
The controversy and disagreement about categories is due to TWO DIFFERENT understandings about what a category is. I'd like to propose that what we are talking about is really CATEGORIES and CLASSIFICATION. The current system and rules for CATEGORIES is trying to set up a system of CLASSIFICATION; a logic that puts every article in a well organized hierarchy. CATEGORIZATION, on the other hand, tries to associate related articles in many different ways.
So perhaps what is needed is BOTH. So I propose:
# Get rid of the constraints on CATEGORIES discussed in sections above.
# ADD A NEW FEATURE, that of CLASSIFICATION, which puts each article in just one location in a hierarchy.
How it might work:
You would type something like ''Class:Bridges in New York City'' (in brackets), and just like categories, it would end up in the appropriate classification page. Either the system would only allow one classification or editors would limit the classifications. Perhaps the classification would appear at the Top of an article (in small print under the article title). This might become an option that could be turned off.
This might make everyone happy. User:SamuelWantman 20:35, 31 Jan 2005 (UTC)
:I don't think this helps. I could see plenty of room for argument over which single classification is the best to use and whether the classification is too specific or too broad. —User:Moverton 04:38, Feb 1, 2005 (UTC)
::Yes, there would be arguments about classification, which is what we often have now with categories (constrained as they are). The people who WANT to argue about classifications could. The rest of us would not have to bother and just add categories. User:SamuelWantman 07:21, 1 Feb 2005 (UTC)
==Arithmetics==
Are here categories Arithmetics that could answer to queries?:
#Intersection - what belongs to two categories.
#Substraction - what belong to one category, but not other
User:Conan 20:43, 3 Feb 2005 (UTC)
== Related category proposal ==
I think I've got it...
The problem is that we are doing multiple categorization and then putting subcategories in whatever category is related. This is a good thing, but it creates problems, like the "no super/sub entry duplication" rule. Take the example of bridges. There is a hierachy under :Category:Toll bridges in the United States. Down that hierarcy there is :Category:Toll bridges in New York City. But there is also a hirearchy under :Category:Bridges in the United States. Down that hierarcy there is :Category:Bridges in New York City. Putting the toll bridge categories as subcategories of bridges is really just putting a related category and not really a subcategory because that subcategy is already part of a different hierarchy. Because of this, it would make sense for ALL the bridges to be listed in Category:Bridges in New York City, and have some entries duplicated in Category:Toll bridges in New York City. So we really have two different things going on; Subcategories and Related subcategories.
My proposal is to make Subcategories and Related Categories different things. Subcategories could look and work the same as they do now. But perhaps we could add :Category:Bridges in New York City#Related and instead of being listed in the subcategory section, it would get listed in a new section called (you guessed it), "Related subcategories". It seems that any given category should be limited to being a subcategory of just one category, so perhaps, this could work by just putting the category first and any following category entries would become "Related subcategories". This might be the simplest way to implement this. Unfortunately, it would mean that many articles would have to be edited to get the correct category on top. User:SamuelWantman 04:55, 5 Feb 2005 (UTC)
:I have no problem with the idea of adding "related categories", possibly as an optional thing (not controlled by software) in the same way as zeal.com does it (eg http://www.zeal.com/category/manage.jhtml?cid=560009). But it's not the same as those bridges. The category :Category:Toll bridges in New York City should be a subcategory under :Category:Bridges in New York City. New York, NY, toll bridge articles will go in the former (ie the bottom level), not in the latter. I ''DO NOT AGREE'' that "any given category should be limited to being a subcategory of just one category". User:Robin Patterson 05:29, 5 Feb 2005 (UTC)
::Well, it might be possible that a category could reasonably fit in as subcategories in two different hierarchies, but no examples come to mind right away. I'll think about that one. But, what is wrong with saying that articles should not be listed more than once in any hierarchy? My problem is the unreasonable intersection of the Bridges and Toll Bridges hierarchies that removes all toll bridges from the Bridges hierarchy. Why? What is wrong with them being in both places? Please give me some concrete reason. I don't understand why this is bothersome to so many people.
::Let me give you a hypothetical example. Let's say there is a category called "People named Bob" (Perhaps there is one!) I know there are clubs for people named Bob, so it seems legitimate that there be a hierarchy of categories for people named Bob. Perhaps it gets organized geographically. If so, there might be a subcategory called "British writers named Bob". Now, if this becomes a subcategory of :Category:British writers does that mean that all the British writers named Bob should be removed from :Category:British writers? User:SamuelWantman 07:30, 5 Feb 2005 (UTC)
:::To answer your last question, under the current system the answer is more often than not ''yes''. —User:Moverton 08:04, Feb 5, 2005 (UTC)
==Category and Template specificity?==
I didn't notice clear guidelines on the project page about how microscopic Cats and Templates should be--anybody know if such guidelines exist or have been discussed? Or am I the only person that finds :Category:Unincorporated community in Seminole County, Florida with a state road passing through it stubs and Template:Unincorporated-community-in-Seminole-County-Florida-with-a-state-road-passing-through-it-stub a bit over-the-top? User:Niteowlneils 22:47, 6 Feb 2005 (UTC)
:I suspect that the category and template in question were created specifically to ''be'' over-the-top. People are not generally creating such categories and seriously using them. (But if you find that such categories exist, please do nominate them for deletion. We discussion too-specific catgories all the time at :Wikipedia:Categories for deletion.)
:Guidelines regarding specificity of categories depend somewhat on the number of articles involved. (A very general subject that we don't write much about obviously does not need specific subcategories. A specific subject that is written about constantly may require more specific subcategories.) I did find this under "Category membership and creation": "A few categories do only merely subdivide their parent category, ''but unless the parent category has many potential articles under it, or many potential subdivisions'', if you can't think of a second parent category, it might be a better idea to fold your smaller category into the parent" (emphasis added). -User:Aranel ("Sarah") 23:34, 6 Feb 2005 (UTC)
== Help requested with :Category:Albums by artist ==
This category is huge, hundreds and hundreds of ''subcategories''. Because of this, only about 3 letters at a time are shown. It takes quite a bit of time to get to the end of the alphabet. I'm wondering how big categories should be handled. The guidelines say to divide things into new subcategories. Since this is a huge category of ''subcategories'', that means adding another layer of hierarchy.
I gave that a try: I created a new subcategory :Category:Albums by artist: A-Z, but it would take forever to move everything into new subcategories. Can this process be automated? If so how? Is there a better solution?
Since the issue of large categories has come up in previous discussions, and seems to be controversial, Is there any way to make a table of contents for a category? It seems that this would be really usefull, and would ease people's dislike of large categories. I tried making a TOC by typing :Category:Albums by artist&from=First \"A\" entry which resulted in :Category:Albums by artist&from=First \"A\" entry, etc... but that didn't work. Is there any way to do this?
It seems that any category that is too big to be shown on one page should AUTOMATICALLY have a table of contents. This should be in the software. Has this been discussed?
Thanks, User:SamuelWantman 07:36, 7 Feb 2005 (UTC)
:I just did a quicky (maunual) A,B,C,... index using URLs the software seems to interpret correctly. I agree it would be nicer if there was a wiki reference (perhaps something similar to [:Category:Albums by artist#A] ) or if the software did this automatically, but for what you seem to want I think this is an adequate workaround. -- User:Rick Block 14:55, 7 Feb 2005 (UTC)
::I've played with this a bit to try to get rid of the external link indicator (present with the default skin, but not the "classic" skin which I usually use), and as far as I can tell there is simply no way. Seems like a link of the form [http:/w/index.php?anything] should NOT be presented as an external link (since it is by definition a link served by the same web server). I suspect a more elegant looking solution for the standard skin will require some sort of software change (sigh). -- User:Rick Block 21:01, 7 Feb 2005 (UTC)
==Category Table of Contents now possible==
Based on Rick Block's work above, I created a template for adding Table of Contents to large categories. To use, type ''[/relativepath] (and variants) as legitimate (relative) URLs and not generate external link indicators (regardless of user's skin choice). -- User:Rick Block 05:35, 9 Feb 2005 (UTC)
:::According to User:Angela on the Wikipedia:Help desk recently, you can use class="plainlinks". [http://en.wikipedia.org/wiki/Main_Page Wikipedia] is shown as [http://en.wikipedia.org/wiki/Main_Page Wikipedia] rather than [http://en.wikipedia.org/wiki/Main_Page Wikipedia]. (Note that in some browsers it still leaves a space the size of the extlink indicator; not ideal, but better than nothing. HTH!) — User:CatherineMunro\User_talk:CatherineMunro 12:05, 9 Feb 2005 (UTC)
:::Thanks, Catherine! -- User:Rick Block 14:39, 9 Feb 2005 (UTC)
User:Henrygb Created a varient of which he named ''Classification: :category:Bridges: :category:Bridges by country: :category:Bridges in the United States: :Category:Bridges in New York: New York City
Classification: :category:Transportation: :category:Transportation by country: :category:Transportation in the United States: :Category:Transportation in New York::Category:Transportation in New York City: Bridges
: This example shows that there are two hierarchies that converge. Putting the classification on the category page makes it very easy to jump to the top of the hierarchy. Notice I did not include Science, Applied science, engineering, etc... in the 'Bridge' hierarchy. I think there is a natural starting and stopping point for each hierarchy.
:Showing the classification also helps make it clearer which categories are RELATED categories and which are part of the hierarchy. In the example above: :Category:Toll bridges in New York City is a related category because it is part of a different hierarchy.
:2) I'd propose that the software be changed so that when users are looking at a category page, they could distinguish which sub-categories are part of the hierarchy and which are just "related" categories. This could be accomplished by making something like CategoryR:xxx to designate the category is a related category. The subcategories would be displayed in two groups: SUB-CATEGORIES and RELATED CATEGORIES. (There might also be a need for "Related article" entries in categories, but that is another discussion.)
:3) I propose that we change the rules. I would first propose that the "no duplication of articles being entered in both super and sub category" rule be amended to say "... in the same hierarchy." The reality is that the status quo is constantly broken, and for good reason. Look at the acting categories mentioned above, and also look at :Category:Bridges in New York City. I've added all the toll bridges into this category. They are still in :Category:Toll bridges in New York City, but it is now clearer that they are part of a different hierarchy.
:Categories are still evolving. By loosening the rules further, some creative changes are possible. I'd like to amend the rule above to say "no duplication of articles should be entered in both super and sub categories in the same hierarchy UNLESS THERE IS A GOOD REASON."
One reason, perhaps, why there was a move to make more and more subcategories, and to remove articles from a category whenever they could be found in a subcategory is because only 200 entries can be shown on a category page. Recently, we have found a way to make :template:CategoryTOC that create a table of contents for large categories that make this a little less of a problem. Perhaps we can work out some other ways to make categories more useful and easier to use. I'm offering this as a start. -- User:SamuelWantman 08:00, 19 Feb 2005 (UTC)
:The problems you mention are real, but I don't think the proposed solution is advisable. I believe the developers intend to eventually introduce the ability to list all of the articles in a user defined hierarchy. If someone is interested in all the bridges of New York City they will be able to automatically generate a single alphabetized list. If they are only interested in those without tolls they will also be able to find a list of those. It is far better to wait for this feature to be introduced than it is to manually overhaul the entire categorization system. Especially since once the software is improved these changes would all have to be reversed. - User:SimonP 16:55, Feb 19, 2005 (UTC)
::Can you reference the proposed change, and the discussion around it? --User:SamuelWantman 20:18, 19 Feb 2005 (UTC)
::: That's what I posted on User talk:SamuelWantman#More on categories. I think there are a few more bugs about this in zilla, though. I do think, however, that category breadcrumbs would be a great feature to add to the software. – User:Flamurai (User talk:Flamurai) 08:21, Feb 20, 2005 (UTC)
::::Thanks for the references, which I had read. But, Both of these appear to be just proposals, and it doesn't seem certain that they will be implemented. The discussion should be happening here to decide what is needed, how much should be software, and how much done by editing. Perhaps there was discussions in the archives about this. Was there a clear consensus about what should happen? I do not get the sense from the discussions on this page that there was a clear consensus. If there was an agreed upon plan for a future upgrade, it should be spelled out clearly on the categorization page. If there wasn't, let's do it now. -- User:SamuelWantman 08:49, 20 Feb 2005 (UTC)
== categorizing user pages ==
I'm starting to see a disturbing trend of people categorizing other user's pages, usually in a non-beneficial and sometimes negative way (ex. :Category:Wikipedia:Suspected sockpuppets, :Category:User:Vacuum:Comments). I'd like to propose rewording the Wikipedia:Categorization#User namespace section to make it clear that only self-categorization of user page is appropriate. I'd also like to make the distinction to specifically mention that categorizing Talk page is not appropriate either. I think the intent here is to keep the category space from being needlessly cluttered with user pages (since that is of little value, yet hinders system performance), and only to allow them if the user "self-identifies" in a particular category. Without such wording, needless categories like the above examples are just going to grow more prevalent, since we can only fall back on the WP:CFD process to get rid of them. -- User:Netoholic User talk:Netoholic 18:09, 2005 Feb 21 (UTC)
== Keying "by blank" categories ==
Should "by blank" (e.g. "by country") categories be keyed as "by blank" or just "blank"? Concrete example for :Category:Music by continent: should it be listed as Music or Music ? My preference is for the former, as it keeps all the related "by" subcategories together. – User:Flamurai (User talk:Flamurai) 02:07, Feb 24, 2005 (UTC)
:Personally, I prefer Music . I might even put it in the first section with Music , but that might be overkill... - User:Dcljr 22:47, 27 Feb 2005 (UTC)
== Noted drug users: how to categorize? ==
It would be useful to have a category that tied together people who are notable in large part for their use or advocacy of pyschoactive drugs. People like Timothy Leary, Hunter S. Thompson, Castenada, Huxley etc. Problem is, I'm not sure what to call it or where to put it. It could go under :Category:Drug culture (although I'm not terribly fond of the phrase 'drug culture') but my main question is, what's a good NPOV and focused cat (one that hopefully won't be used to label people like George Bush whose drug use is incidental to their reason for notability). All I've come up with so far is 'Noted drug users'. Aside from being too broad (it could be applied to GWB and Dean Martin) the word 'drug' itself can be pretty ambiguous. The best description would be 'Noted experimenters with psychoactive substantives' but of course it's much too long. Any suggestions? Or do you think it's just a bad idea. --User:LeeHunter 20:06, 26 Feb 2005 (UTC)
:Not everything needs to be a category - this strikes me as something that might be more appropriately dealt with in a list article or an article about the history of popularization of drug use (if that's what you're really getting at). -- User:Rick Block 00:34, 27 Feb 2005 (UTC)
::Thanks for the suggestion. I've create List of notable drug culture figures for now. I still see some value in using a category, but perhaps I'll leave that for a later date. --User:LeeHunter 14:10, 27 Feb 2005 (UTC)
:In any event, if you do this via a category, do make sure to write a clear explanatory note in the category page, because no name is going to be crystal clear. So to speak. -- User:Jmabel | User talk:Jmabel 02:58, Feb 27, 2005 (UTC)
==Category==
Could it be done by changing the text of the stub template to Stubs (start with {}). When the tag is added to an article start with the letter A, it should be added as . This will link articles with the stub template to the corresponding stubs categories according the first letter of the title. — User:InstantnoodUser_talk:Instantnood 07:30 Feb 26 2005 (UTC) (copied from Wikipedia talk:WikiProject Stub sorting#What links here versus stub category ) — User:InstantnoodUser_talk:Instantnood 11:39 Mar 1 2005 (UTC)
: What is the problem to which this is a proposed solution? -- User:Jmabel | User talk:Jmabel 17:03, Mar 1, 2005 (UTC)
== Classification: See Wikipedia:Classification ==
I've started classifying categories. Take a look at :Category:Altos and move up and down the hierarchy about Opera. I've written a page about this at Wikipedia:Classification. Feedback would be appreciated. Thanks. -- User:SamuelWantman 10:47, 17 Mar 2005 (UTC)
:Interesting idea, but it won't work so well if people change the categorization of the subcategories. In other words, the Category feature is a bottom-up solution and you seem to be imposing a top-down (not to mention "by hand") approach with your "Classification" system. The two approaches would seem to be fundamentally at odds with each other. - User:Dcljr 01:55, 23 Apr 2005 (UTC)
:: Yes, but it isn't hard to fix. And I wouldn't do this unless the categories looked to be stable.
::There's an advantage to doing it "by hand". Some subcategory associations are what I call "related" sub-categories, meaning not part of the hierarchy.
::Bottom-down and top-up aren't at odds. People want to move in both directions. -- User:SamuelWantman 06:20, 23 Apr 2005 (UTC)
:::As a user, I often start from an article, find a relevant category, navigate up the hierarchy a level or two, then navigate down. -- User:Jmabel | User talk:Jmabel 23:29, Apr 23, 2005 (UTC)
== Categories: A compromise? ==
The conversation has been quiet for a while. I'm wondering if the advent of Category TOC's has changed anyone's view on the Super/Sub category issue?
Re-reading all the discussions, I'd say that there was no clear consensus as far as I could tell. Can we agree to let things evolve and see what happens? I'm thinking of the following:
1) Ease up on the no Super/Sub-Category duplication rule. Duplications seem to arise naturally. We should agree to allow duplication when it makes the categories more complete, less confusing or in other ways more useful. I think the rule of thumb could be:
:If there aren't subcategories for every member of a category, there can be duplication. Thus, Oscar winners could duplicate film actors, Film musicals could duplicate musicals, Toll bridges could duplicate Bridges, Actors could duplicate African-American actors, etc... This would also hold if the subcategories are more than one level below. So since the entries for Directors by Nationality are two levels below Directors (and many directors are multi-national), there could be duplication.
2) When entries are duplicated, the duplication should be noted. See: :Category:Bridges in New York City for an example of how this could be done.
3) Only bend "the rule" with restraint. We're not agreeing to include articles at more than two levels of a hierarchy. There should be a good reason for any duplication. Duplications should only happen if they make categories easier to use. Exceptions of a type that we haven't discussed should be brought up at this page for discussion.
4) A policy on exceptions should be added to the category page if we can reach a consensus.
Can we live with this as a compromise?
::--User:SamuelWantman 11:14, 17 Mar 2005 (UTC)
:I won't oppose it, but I will point out that looser rules are harder to enforce. Can we at least limit firmly ''how many'' levels in a hierarchy may be used for a given page? Otherwise, I can imagine the same item being put (for example) at six different levels of a hierarchy. -- User:Jmabel | User talk:Jmabel 18:21, Mar 17, 2005 (UTC)
:: I suggested two levels (see #3 above). I think this could be all spelled out so that pandemonium doesn't become the norm. Do you think #1-#3 above (with # 3 stating examples which have been discussed) is enough of a guideline for exceptions, or is more needed? -- User:SamuelWantman 19:58, 17 Mar 2005 (UTC)
:::Ah, hadn't noticed that. I'd be open to this as long as a reasonably large group is willing to commit to monitoring this: it's a more difficult criterion to monitor than the current one. -- User:Jmabel | User talk:Jmabel 20:27, Mar 17, 2005 (UTC)
== nominations for trivial deletion/moves? ==
I've been trying to find where I should list a mispelled category I created. I may be going blind because, despite WP:CFD stating: ''Read and understand Wikipedia:Categorization before using this page. Nominate categories that violate policies there, or are misspelled, mis-capitalized, redundant/need to be merged, not NPOV, small without potential for growth, or are generally bad ideas.'', I can't find a nomination list. Would somebody who knows what is going on, please make the nomination list more prominent or change the text at CFD? Oh, and if anybody wants to move :Category:Coup d'états to :Category:Coups d'état, I would appreciate it. (Foreign language conjugations... bah!) - User:BanyanTreeUser:BanyanTreeTree">User talk:BanyanTree 14:21, 21 Mar 2005 (UTC)
:I changed it to "Nominate categories that violate policies here". User:Dbenbenn | User talk:Dbenbenn 14:57, 24 Mar 2005 (UTC)
::Thanks for the clarification. - User:BanyanTreeUser:BanyanTreeUser talk:BanyanTree 23:56, 24 Mar 2005 (UTC)
== Namespace and VFD ==
This paragraph, headed Wikipedia namespace:
:Categories relating to the Wikipedia:project namespace should be added only to the Wikipedia:talk page of articles. For example, tags suggesting the article is :Category:To do, or is listed on WP:VFD would be placed on the talk page as they are relevant to editors, not an aid to browsing in the way ordinary categories are. Please use
Categorization
''For Wikipedia's categorization projects, see Wikipedia:Categorization.'' ---- Categorization is the process in which ideas and objects are recognised and understood. Categorization is fundamental in decision making and in all kinds of interaction with the environment. There are, however, different ways of approaching categorization. ==The Classical View== The classical Aristotelian view that claims that categories are discrete entities characterized by a set of properties which are shared by their members. These are assumed to establish the conditions which are both necessary and sufficient to capture meaning. ==Cognitive science== Since the research by Eleanor Rosch and George Lakoff in the 1970s, categorization can also be viewed as a the process of grouping things based on prototypes - the idea of necessary and sufficient conditions is rarely if ever met in categories of naturally occurring things. It has also been suggested that categorisation based on prototypes (see Prototype (linguistics)) is the basis for human development, and that this learning theory (education) relies on learning about the world via embodiment. A cognitive approach accepts the fact that natural categories tend to be fuzzy at their boundaries and inconsistent in the status of their constituent members. Systems of categories are not objectively "out there" in the world but are rooted in people's experience. Conceptual categories are not identical for every speaker of a language. Categories form part of a hierarchical structure when applied to such subjects as taxonomy in biological classification: higher level: life-form level, middle level: generic or genus level, and lower level: the species level. These can be distinguished by certain traits that put an item in its distinctive category. But even these can be arbitrary and are subject to revision. Categories at the middle level are perceptually and conceptually the more salient. The generic level of a category tends to elicit the most responses and richest images and seems to be the psychologically basic level. Typical taxonomies in zoology for example exhibit categorisation at the embodied level, with similarities leading to formulation of "higher" categories, and differences leading to differentiation within categories. ==See also== * semantics Knowledge representation Philosophy Semantics
Categorization
: ''See also: Wikipedia talk:Categorization'' For those for whom this won't be obvious, the content of this page appears to be very inspired by George Lakoff. That's not a bad thing (I like Lakoff), but it should eventually be clarified in the article, and competing views should also be included. --User:Ryguasu 02:57 Nov 25, 2002 (UTC) : I added a link to Lakoff, expanded slightly, wikified a little, and removed the Wiktionary tag. User:Spalding 13:11, Apr 3, 2005 (UTC) == Perceptual categorization? == We should formulate an amendment to this entry to consist of information detailing the science of perceptual categorization. That is, the way people determine an individual or group's thematic status (e.g., reformer, deathbringer, atheist, Christian, scientist). Of course, this topic may be covered elsewhere. If so, then we should amend the article to disambiguate. User:Adraeus 14:35, 10 Dec 2004 (UTC)
Categorization
This article provides guidelines on creating and organizing categories. For a quick introduction to categories, see Wikipedia:Category. For everything you ever wanted to know about categories, see Wikipedia:Categorisation FAQ. ==When to use categories== Every page in the article namespace should have at least one category. Categories should be on major topics that are likely to be useful to someone reading the article. :Article: Michael Jackson :Useful category: :Category:Pop singers :Not useful: ''Category:Musicians whose first name starts with M'' Questions to ask to know if a category is the appropriate tool: *Is it possible to write a few paragraphs or more on the subject of a category, explaining it? *If you go to the article from the category, will it be obvious why it's there? Is the category subject prominently discussed in the article? If the answer to either of these questions is no, then a category is probably inappropriate. An article will often be in several categories. Restraint should be used, however — categories become less effective the more there are on a given article. An article should not be in both a category and its subcategory, for example Microsoft Office is in :Category:Microsoft software, so should not also be in :Category:Software. An article with the same name as a category should usually belong only to that category, for instance, Deism belongs only in :Category:Deism. Categories appear without annotations, so be careful of NPOV when creating or filling categories. Unless it is self-evident and uncontroversial that something belongs in a category, it should not be put into a category. Exceptions to the above rules are categories such as :Category:Stub categories which are intended to aid the function of Wikipedia editing. For alternative methods of grouping articles, and the circumstances in which they should be used, see Wikipedia:Categories, lists, and series boxes. === Categories vs. Lists vs. Info boxes === See: Wikipedia:Categories, lists, and series boxes === Categories applied to articles on people === A separate wikipedia page Wikipedia:Categorization of people was created to help you in designing, applying and checking categories that are used for articles on people. ==Categories do not form a tree== Each Wikipedia article can appear in more than one category, and each category can appear in more than one parent category. Multiple categorization schemes co-exist simultaneously. In other words, categories do not form a strict hierarchy or tree structure, but a more general directed acyclic graph (or close to it, see below). Nevertheless, parts of the category graph will be tree-like, and it may be convenient to think of parts of the category graph as being like multiple overlapping trees. ==Cycles should usually be avoided== Although the MediaWiki software does not prevent cycle (graph theory) (loops), these should usually be avoided. ==Guidelines for assignment of categories== ===How to create categories=== Creating a category is as simple as adding a soft link to the appropriate article in the Category: namespace; for instance, to add Felis silvestris catus to the "fluffy creatures" category, you would edit the article and enter
Categorization
*Old talk at Wikipedia talk:Categorization/Archive 1 *Archived main page discussion on Hierarchicalization at Wikipedia talk:Categorization/Archive 2 *Further discussion at Wikipedia talk:Categorization/Archive 3 *Further discussion at Wikipedia talk:Categorization/Archive 4 (archived on 4 September 2004, includes material up to approximately 20 Aug 2004) *Further discussion at Wikipedia talk:Categorization/Archive 5 Includes material up till about 8 September 2004 *Further discussion at Wikipedia talk:Categorization/Archive 6 Includes material up till about 30 September 2004 *Further discussion at Wikipedia talk:Categorization/Archive 7 Includes material up till about 22 January 2005 ==Category - Images "OF" People should not mean "WITH" people, should it? == Are too many images merely with a person somewhere in the picture being included in the category "images OF people"? User:Wikityke 22:15, 4 Feb 2005 (UTC) Discussion at Category_talk:Images_of_people == Super Categories == This category/supcategory thing needs some rethinking. As I see it, the general rule that "if something is in a subcategory, it shouldn't also be in the supercategory" often does not make sense. Sometimes the subcategories mark clear distinctions between things, but sometimes the subcategories are just unimportant attributes imposed on the category. I'll give you some examples that make sense: :Category:Musical theatre has two subcategories; :Category:Operettas and :Category:Musicals, both of which have all the articles about individual works of Musical theatre. This makes sense because: * There is very little overlap between Operattas and Musicals, they are almost distinct categories * Most people looking for a list of works would find this distinction helpful. * The distinction that makes the subcategory is intrinsic to the category, not just a randomly chosen attribute. For instance, the works could be in subcategories that intead of using Operetta and Musicals could have used the year they were composed. This would not be very helpful for someone looking for a list of musicals. :Category:Musicals has the subcategory :Category:Musical films. This is a trickier situation. Some of the articles in Musicals are in both categories. For some titles there are seperate articles for both the movies and the theatre productions. This makes sense because: * If Wikipedia were complete there would be seperate articles for both * The films almost always come after the theatre productions An argument could be made for making Musical Films a subcategory of Musical Theatre instead of Musicals but it doesn't really matter. Some categories do not work so neatly. An example which is really bothersome is :Category:Film directors which has the subcategory :Category:Film directors by nationality which has 28 subcategories. It does not make sense to have each director only listed in a subcategory by nationality. The nationality of the director is interesting, but not all that important. Some directors start in one country and move to another. I have no problem with there being categories for directors by nationality, but I think ALL of them should also be in the directors category. The reason for this is: * Having them in both categories makes it easier to find a director if you know his nationality, and MUCH easier if you don't know his nationality. Which brings me to :Category:Bridges in New York City. This category has the subcategory :Category:Toll bridges in New York City. Whether a bridge has a toll or not is not all that important, and the attribute does not instruct the reader to notice something important about bridges. If you want to see the articles about the bridges in New York City, why should you have to look in two places? The notion that articles should not be listed in categories and subcategories strikes me as an artifact left over from libraries. The beauty of hypertext is that things can be linked many ways, not just organized on shelves. Why can't things be in multiple categories? I'd like to see ALL the bridges in New York State listed in :Category:Bridges in New York. This makes it easy to see a list of all the bridges in a geographical region, and also the subregion. I made the change for all the bridges in New York City. But within a day they were all reverted. I'd like to do it for bridges the rest of the world, film directors and some other categories, but I know I need the consensus of everyone else. I've read most of the discussion relevant above, and I don't see a good argument for keeping things the way they are. The important thing is to make Wikipedia USEFULL. User:SamuelWantman :Yes, I quite agree. I made a similar point when User:SPUI moved Indiana Toll Road and Ohio Turnpike from :Category:Transportation in Indiana and :Category:Transportation in Ohio into :Category:Toll roads in Indiana and :Category:Toll roads in Ohio. I objected that both roads are very prominent fixtures of the transportation systems in both states, and are, as far as I know having lived in both states for many years, the only toll roads in either state. While it is quite possible that there may indeed be some other toll roads in those states, those have nowhere near the recognition of the ones mentioned above. It makes no sense to me to place these roads into what are currently (and as far as I can tell, for the forseeable future) single-item subcategories. I don't really see the point of the toll road sub-categories in these states where toll roads are relatively uncommon, if not singular entities. But while I'm willing to leave these subcategories be, it seems ridiculous to me to only categorize such prominent features of the transportation systems of those states in minor subcategories. I might note that many of the other by-state subcategories under :Category:Toll roads in the United States are also single-item categories--though since I'm not familiar with those states I can't really say anything about the relative prominence of the roads in those states. User:Bkonrad≠User talk:Bkonrad 02:31, Jan 31, 2005 (UTC) ::Actually, the Ohio Turnpike is really only relevant if you live in northern Ohio, but I see your point. I think the point of putting it in its own subcategory is to make navigation via :Category:Toll roads in the United States more consistent. However, there is no clear policy on whether it makes any sense to have one-member categories for navigational purposes. (Though the current trend is to say that yes, it does. See :Category:Albums by artist.) Anyway, with the toll roads, I would just about go as far as saying that there is little point in having individual state subcategories; there aren't ''that'' many toll roads. ::For film directors, it is against current policy to put them in both a specific nationality category ''and'' the parent :Category:Film directors. All members of subcategories are supposed to be considered members of the supercategory. The current wiki software doesn't allow that, but that doesn't make it any more useful to throw all the film directors into one unorganized mess. (Also, huge supercategories make it harder to ''find'' the subcategories with the current system. If there are more than 200 members, you start having to go through pages to find the children categories.) Ideally, of course, we could put an article in :Category:Film directors and a nationality category and look up the intersection of the two, but at the moment that isn't possible. ::(Note: If you know the name of the director, you're not going to be looking up the article via categories, anyway. Huge categories are not helpful to casual browsers.) :::Category:Musical films is a special case. (There ''are'' actually musical films that were not ever stage musicals. See for instance ''Moulin Rouge!''.) Ideally, we would come up with some term for musicals that appear on stage and make that a sibling. -User:Aranel ("Sarah") 03:07, 31 Jan 2005 (UTC) I agree with Samuel that the category/subcategory thing is a problem. I've been thinking about it for a while, and here's what I decided: The reason for the difficulty with :Category:Film directors vs. :Category:Film directors by nationality is that :Category:Film directors by nationality is fundamentally flawed. We shouldn't have subcats for "randomly chosen attributes", as Samuel put it. Instead, have * :Category:People by occupation with :Category:Film directors as a subcat * :Category:People by nationality with country subcats and other random things like * :Category:People by height with a subcat for each, say, centimeter * :Category:People by handedness with left and right subcats etc. Then we need a software feature that allows a page to represent the intersection of some categories. So, for example, if I decide I want to see all left-handed Hungarian film directors, I can just request the intersection of :Category:Left-handed people, :Category:Film directors, and :Category:Hungarian people. I don't have to explicitly put people into :Category:Left-handed Hungarian film directors, as now. Under this scheme, it would be possible to categorize a person with all their attributes (height, handedness, occupation, etc.) without having to worry about explicitly making intersection categories. The category organization would become flatter, with many current subcats replaced by the new software feature. I think this proposal would neatly solve the problem that Samuel described above. User:Dbenbenn | User talk:Dbenbenn 04:13, 31 Jan 2005 (UTC) Another example: the proposed intersection feature would allow you to find people who were born in 1850 and died in 1950 as the intersection of :Category:1850 births with :Category:1950 deaths. As it is now, you'd need a :Category:1850 births, 1950 deaths, which would just be silly. User:Dbenbenn | User talk:Dbenbenn 04:29, 31 Jan 2005 (UTC) : That's quite a good idea. I wonder if it's feasible performance-wise. The other problem I forsee is there's no obvious user interface. – 04:19, Jan 31, 2005 (UTC) :: Thank you :). I haven't really thought about how the user interface would work yet. You would definitely want to be able to link to the intersection of two categories. One possibility: you could, for example, simply make a page :IntersectionCategory:Left-handed Hungarian film directors with the content :::