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[edit] Templates in article space

We need to spell out guideline on where templates are categorised. -- Alan Liefting (talk) - 22:05, 20 August 2009 (UTC)

Besides the template specific categories or limit them to only those categories? Vegaswikian (talk) 00:39, 21 August 2009 (UTC)

That is what I want spelled out. Some editors do not follow that system. I have encountered it most recently at Template talk:San Jose and Silicon Valley attractions#Navbox collapse settings and category. -- Alan Liefting (talk) - 00:45, 21 August 2009 (UTC)

I have no objection to making it clear that templates do not belong in article categories. This is especially confusing when they are sorted to the top of the list. Vegaswikian (talk) 02:39, 21 August 2009 (UTC)

And that is what I would like to have spelt out in the guideline. -- Alan Liefting (talk) - 10:16, 21 August 2009 (UTC)

Let's say we have a book series called "Friends of Vivian". And somebody made a nice Template:Friends of Vivian to list all books in that series, to be put at the bottom of all the articles on all those books. In what category/ies should that template be categorised?

None but Category:Book series templates?
Also Category:Friends of Vivian templates?
Also Category:Friends of Vivian?

If you say "also Category:Friends of Vivian templates", then such a category would contain probably two templates at most: Template:Friends of Vivian and Template:Friends of Vivian stubs. And is that a good idea, to have such small categories?

If you would say "none, but Category:Book series templates?", it would be too hard for editors to find out about the existance of the template, so that is unwise.

So I'd choose the 3rd option. What do you say? Debresser (talk) 07:29, 21 August 2009 (UTC)

1, or if it exists, 2. The purpose of main space categories is not to find templates, it is to find articles. If the template already exists in all of the articles, as it should, then it is not difficult to find. If you really still can't find the template, what links to the article should show a link from the template. Vegaswikian (talk) 07:34, 21 August 2009 (UTC)

Without agreeing or disagreeing, I'd say that this is precisely the question: whether a category should include only articles or not. Perhaps there is something to say for having templates, portals and whatever else in the category also. (After all, a category has not only articles: it has categories also, which we call subcategories.) Debresser (talk) 10:06, 21 August 2009 (UTC)

I think we have to imagine what a casual or new user to Wikipedia will see when they go to a category. I find that the listing of templates, and even worse -- the transclusion of templates so that they appear on the category page (example), are distracting and confusing. I do not think templates should be on category pages nor listed in categories (except for template categories). -- ☑ SamuelWantman 08:32, 21 August 2009 (UTC)

We need to distinguish between content and editing categories. Content is for readers and editing it for editors. Stubs, WikiProjects, templates, Wikipedia namespace pages and user pages are all for the use of editors and should not be in content categories. As things currently stand there is a good separation between content and editing categories except for the stub categories. -- Alan Liefting (talk) - 10:16, 21 August 2009 (UTC)

Well, this has sat for a while and there appears to be consensus from the small number of participants in the discussion. Is this strong enough to make the change? Vegaswikian (talk) 07:16, 22 September 2009 (UTC)

[edit] Categorization of fictional characters with real people

I have a question about categorizing fictional characters.

Is it appropriate to place an article (or redirect) about a fictional character in a category that is populated mostly with real people? The following example is why I ask: we have Category:Abraham Lincoln High School (Brooklyn, New York) alumni, and it's been defined as being a holder for "articles about former students and alumni, real and fictional, of the Abraham Lincoln High School ...". So we have Jesus Shuttlesworth included, a fictional character from the movie He Got Game.

I've never before seen fictional and real people mixed together like this—should it be done? I looked for a guideline on this question and couldn't come up with anything. The closest to being on point was Wikipedia:Categorization of people#Keep people categories separate, which talks about keeping categories for people limited to people, but it seems to largely be referring to biographical articles vs. institutional or event articles, not real people articles vs. fictional people articles.

(With the Jesus Shuttlesworth example, there is no question that it's verifiable that in the fictional world he is indeed an alumnus of the school in question.) Good Ol’factory ^(talk) 23:07, 21 September 2009 (UTC)

Any article on a fictional person should make it immediately clear that the subject is fictional. Unfortunately, that is not something that would be known from just reading the list of titles in the category. Moreover, the category could conceivably be used by readers without them drilling through to the individual articles. Since there is no consistent naming convention or other marker that would make the fictional nature of the subject clear on the category page, mixing the real and fictional people in one category doesn't seem right to me. I do think that a sub-category for fictional alumni would be acceptable, if there are enough articles to warrant one. (One article doesn't seem enough.) --RL0919 (talk) 23:45, 21 September 2009 (UTC)

No fictional character work anywhere because they don't exist! This sub0categorisartion is nonsense. -- Magioladitis (talk) 23:55, 21 September 2009 (UTC)

I agree with the arguments of the previous users that it is not enough that the article of a fictional character should make that fact very clear, but likewise categories for fictional characters should state so specificely. Preferably in their title (and in the text of the category page). We could have Category:Fictional Martians, but not Category:Martians. Not yet, at least. Debresser (talk) 09:58, 22 September 2009 (UTC)
- Unless there are no real members of the category, as with martians, the category name should expressly state that it is for fictional subjects. Otherwise, it is for real subjects only. It's simply a bad idea to mix real people and fictional characters in the same category; we don't need a guideline to tell us that. Postdlf (talk) 13:21, 22 September 2009 (UTC)

Agree with others above. Any references that place a fictional person at, for example, a particular school, can and should be read to mean in the fictional universe. As such, they shouldn't share categories with real people. As RL0919 states, simply looking at a category listing doesn't tell you if the entry is fictional or not. If there are enough fictional entries, a separate "Cat:Fictional alumni at whatever school" or some such is more appropriate. --Kbdank71 15:11, 22 September 2009 (UTC)

I'm sure Jimbo would love the headline, "Wikipedia contributors believe David Palmer was a real U.S. president." Postdlf (talk) 17:32, 22 September 2009 (UTC)

Good point. --Kbdank71 18:05, 22 September 2009 (UTC)

I fixed the problem by creating a subcategory for fictional alumni and moving the character redirect there. I don't care whether it gets CFD'd, but under no circumstances should fictional subjects be categorized as members of a series with real subjects, regardless of whether a separate category for fictional subjects exists. It's simply inaccurate, misleading, and confusing, and looks completely foolish. A category about a subject could contain both, but never a "list" category like this alumni one. Postdlf (talk) 20:02, 22 September 2009 (UTC)

I removed the category again. This is a redirect we are discussing and the fact that some reference says something about this character being in this university it's not even important! -- Magioladitis (talk) 20:07, 22 September 2009 (UTC)

Whether the alumni status of the character is significant enough to categorize is a separate fight that I don't think we should get into here, because it's specific to that subject rather than a matter of general principle. The fact that it's a redirect shouldn't matter, because the categorizing of redirects allows us to classify elements or subtopics of articles without forcing the whole article into a tangentially-related category. So it's a good thing. But please discuss elsewhere whether an alumni cat should apply at all to the redirect; this thread is purely about how to deal with fictional and real subjects in the same category and I'd rather not confuse the issues. Postdlf (talk) 20:33, 22 September 2009 (UTC)

I took a stab at writing some guideline language for separating fictional from non-fictional subjects here. Postdlf (talk) 20:33, 22 September 2009 (UTC)

As I can rest assured that the conclusion of the discussion will be made independently of whatever opinion I express here, I will refrain from opining, though I guess that one could speculate accurately based on my actions here that somehow precipitated this Wikipedia-wide test case. The sources re Shuttlesworth are ironclad, and his "attendance" at the high school is a defining and non-arbitrary characteristic. There are plenty of other such potential categorizations, such as adding Peter Parker to Category:People from Forest Hills, Queens, where I had also anticipated adding fictional residents. Perhaps crafting a definition for "defining" could be our next joint exercise. Alansohn (talk) 22:01, 22 September 2009 (UTC)

Alansohn, I hope you do realise that in bringing this up I wasn't singling you out for attention or derision. This really was the first time I had encountered the issue of a fictional character being categorized with real people. When we couldn't reach a two-party "consensus", I thought it would be worthwhile to bring it up here to get a feel for what others think. Given our past encounters, I was careful not to mention you by name. Substantively, I essentially agree with Postdlf's take on this—we shouldn't worry in this particular discussion about the particular case of Jesus Shuttlesworth—whether or not the attendance at the high school is defining or whether or not the sources are iron-clad—that can be dealt with elsewhere—what we really need to determine is if fictional characters are ever to be categorized with real people. I think it would be worthwhile to hear why you would say "yes". I don't think anyone intends to make a conclusion independently of whatever you might say. Good Ol’factory ^(talk) 22:13, 22 September 2009 (UTC)

"People" means "real people," without question. Ask yourself whether you'd find "Helen Keller, Geraldine Ferarro, and Spider-Man are all people from Forest Hills, Queens" to be a credible sentence. Postdlf (talk) 00:48, 23 September 2009 (UTC)

Any particular reason Category:People from Bensonhurst, Brooklyn was just created with a "real or fictional" definition while this discussion was ongoing and trending towards not including fictional people in real people categories? We haven't even heard an argument yet as to why they should be. Good Ol’factory ^(talk) 02:50, 23 September 2009 (UTC)

The category was cloned from Category:People from Bushwick, Brooklyn. We haven't heard any good reasons why not to cut and paste. Let me know the result of this discussion so that we can move on to defining "defining", a matter that will actually impact Wikipedia in a meaningful fashion. Alansohn (talk) 03:07, 23 September 2009 (UTC)

You can start such a discussion at any time. No need to delay for others to end. Good Ol’factory ^(talk) 03:18, 23 September 2009 (UTC)

In reply to "The sources re Shuttlesworth are ironclad": Show me a source that says "Jesus Shuttlesworth is an alumnus of Abraham Lincoln High School", and I'll show you sources that say "Sylvester Stallone is a Vietnam veteran", "Anthony Perkins is a killer who wears his dead mother's clothes" and "Jada Pinkett Smith is a hippo." But all of these sources are written under the presumption of suspension of disbelief, and are intended to be parsed that way too. Hesperian 03:26, 23 September 2009 (UTC)

I have not pushed here for either side, but I did state that there is no valid argument against their inclusion based on the absence of sources. As I've stated above, I am offering no opinion on the subject, yet you've still managed to completely and utterly misrepresent the statement and the foolish examples you offer only demonstrate the lack of understanding of the issue here. The fictional character Jesus Shuttlesworth attended Abraham Lincoln High School; Ray Allen, the actor who played him did not. That there is no understanding of the difference between Sylvester Stallone, the actor, and John Rambo, the character he played, represents a rather clear inability to understand the issue at hand. Your blatantly erroneous statements need to be reworded to state that "Anthony Perkins PLAYED THE ROLE OF a killer who wears his dead mother's clothes" and "Jada Pinkett Smith VOICED THE ROLE OF a hippo" all of which would be appropriate for categorization. Where there are no categories for the fictional world that are sizeable enough to justify their creation, I see no issue with inclusion in a "real" category. We have (or should have) categories for Category:Fictional Presidents of the United States, Category:Fictional Vietnam veterans, Category:Fictional animals and Category:Fictional killers who wear their dead mother's clothing. Where the fictional category is far too small, such as for the rather WP:POINTy Category:Fictional alumni of Abraham Lincoln High School (Brooklyn, New York), and where the inclusion criteria specify that real people and fictional characters may be included, I still see no issue here. Alansohn (talk) 12:41, 24 September 2009 (UTC)

Do try to engage in this discussion in a constructive manner. This implies addressing my arguments without calling them foolish or suggesting that I lack understanding.

Those "blatantly erroneous" statements are nonetheless drawn from real sources. Yes, these sources need to be read in a particular way. One must recognise that the sentence construction is lax, and what is intended is what you have written above. In the same way, any source that states that Shuttlesworth attended Abe Lincoln High School needs to be read in a particular way: one must recognise that what is being asserted is a premise of a fictional work, rather than a fact. That is my point. Hesperian 13:00, 24 September 2009 (UTC)

I didn't create the fictional alumni category to make a point (what point did you think?), but to quickly solve a problem in a manner most likely to please everyone (at least for the time being). You wanted the redirect categorized by the fictional character's high school attendance, everyone else wanted the fictional separated from the real. I don't care if the category continues to exist, but putting it back in the real alumni category is not an option.

There have been numerous issues raised in this discussion with including real and fictional (and no issue with not doing it, as far as I've seen). One issue with a blended category is that it would be rather useless—no one reading through the category will be able to tell which entries are fictional and which ones are real without clicking on the article link. So a blended category would merge together two lists of two very different things without preserving that difference.

But the biggest issue is that it is simply inaccurate where the category is unavoidably going to be interpreted as only intended for real people notwithstanding any inclusion criteria to the contrary. I don't believe most people would expect to find fictional characters mixed with real people in an alumni category unless it were named "Real and fictional alumni of Foo High School." That a corresponding category specifically for fictional members does not exist is no reason to cause these problems. It looks foolish, like we can't tell the difference between fact and fiction or worse, don't care. Postdlf (talk) 15:27, 24 September 2009 (UTC)

On reflection, the most compelling argument against categorising fictional characters like this is provided by the alternative history genre, where the line is blurred between fictional and real people. What if I put Charles Lindbergh into Category:Presidents of the United States based upon the 2004 novel The Plot Against America? After all, "the sources are ironclad". Hesperian 02:12, 24 September 2009 (UTC)

Still no better. See above. Alansohn (talk) 12:41, 24 September 2009 (UTC)

"Above" does not address this point. If we can put Shuttlesworth into the Abe Lincoln alumni category based on a fictional premise, then we can put Charles Lindbergh into Category:Presidents of the United States based on a fictional premise. Do you object to us putting Charles Lindbergh into Category:Presidents of the United States. If so, why? Hesperian 13:00, 24 September 2009 (UTC)

I'd hope we wouldn't categorize Lindbergh as either a real president or a fictional president; he's not fictional, so he would seem out of place in Category:Fictional Presidents of the United States. I don't believe there is a valid way you can categorize real people by the roles they are given in fiction, particularly with the vast body of alternative history fiction out there. The most notable historical figures would probably have categories for what they actually did swamped by categories for what they didn't. But JFK would be the sexiest fictional robot, of course. Postdlf (talk) 15:27, 24 September 2009 (UTC)

The fictional character Jesus Shuttlesworth attended Abraham Lincoln High School in fiction only. In other words, in the real world, no he didn't. If you go to that high school and check their rolls, you won't find a student named Jesus Shuttlesworth ever having attended there. Since we have many characters for fictional characters, like Category:Fictional Presidents of the United States, we should not create confusion by adding fictional characters to non-fictional categories, simply because there are not enough articles to support a fictional characters category. --Kbdank71 13:21, 24 September 2009 (UTC)

[edit] Categorizing images/files

If an image/file is from Wikimedia Commons, should we still categorize the Wikipedia page that contains the image? Good Ol’factory ^(talk) 03:29, 23 September 2009 (UTC)

That can't be done. The description is just a transclusion of the description page from Commons, and it can't be edited locally. Even more, there's nothing editable in wikipedia about an image in commons to categorize. MBelgrano (talk) 20:04, 23 September 2009 (UTC)

Sure it can: [1]. The WP page is now in Category:Flags, but this is different than the Commons categories if you go to the Commons page. It can be done; my question is should it be done in WP as opposed to just in Commons? Good Ol’factory ^(talk) 21:32, 23 September 2009 (UTC)

Commons could use all the category help it can get, BTW. Many images don't have any categories, and much of the category system is just confused, such as categories for art failing to distinguish where the art was made from where it is currently located. Postdlf (talk) 20:53, 23 September 2009 (UTC)

I have seen the warning that appears when it is attempted to create a new page on the article description, wich says "This image is on Wikimedia Commons—not on Wikipedia. Any descriptions should be placed there. This page should rarely be used except for nominating featured pictures. Please see the image description page on Commons for file information, a list of pages that display this image, or view the full-size version of the image." If I'm told not to create a page, I won't create a page, and without doing so it's imposible to categorize. To do such categorization, we would need to make huge numbers of such pages. I'm sure that this warning wasn't added without strong reasons, and I would bet there must be some technical reasons for this. This topic should be discussed at the village pump, not here, where fewer users follow.

Besides, Wikipedia in english (or any other project) does not have a fraction of the images as a personal scope: all images are potencially usable, and so candidates to be categorized. But, as pointed, all such work would simply duplicate the one done in Commons itself (with the detail that categorization in Common helps users from any project seeking images, while here it's only for local users), and the work in Commons is already requiring a lot of help without it being duplicated elsewhere. Have in mind that there are hundreds of uncategorized images for each day at maintenance, and the ones awaiting categories for the longest time right now go back to 24 July 2008.

A paralel category system at a wikipedia project may be a legitimate project on projects of other languajes (as, due to software limitations, there's no way to implement a multilanguaje category system on a same project, so it is done in english), but for this specific project it would be just duplicated work. MBelgrano (talk) 01:45, 24 September 2009 (UTC)

When you add a category with HotCat it doesn't produce the warning. It seems to just go ahead and create the page. I think this (combined with your comment above) answers my question. Good Ol’factory ^(talk) 01:58, 24 September 2009 (UTC)

[edit] Defining "defining"

The biggest hole that exists at CfD is the inability to define the term "defining". In the real world of article space, there are such guidelines as policies as WP:N that define what it means for an article to be "notable". An article that meets these qualifications is presumed to be notable and editors new and old can work to craft articles to meet that standard. As no such corresponding definition exists for "defining", we are left at CfD with playing a perpetual game to decide if a particular category does -- or does not -- meet the standard for retention. No editor can create a category by following any standard and have some measure of assurance that the category satisfies its requirements. The argument has been made that CfD does have standards, all of which are worded negatively. In other words, we can't tell you what IS defining, but we can tell you what is NOT. I suggest that the following definition be used: "A category is always presumed to be defining per WP:DEFINING, unless its use is specifically and directly excluded by a Category-based guideline or policy that prohibits it." If an editor believes that a category is not explicitly excluded and is thus "defining", the argument would be expressed by stating "Keep per WP:DEFINING". Arguments for deletion would explain how the inherent presumption of definingness is rebutted based on WP:CAT, WP:OCAT or other relevant policies and guidelines. Arguments such as "not needed" or "listify", which are not based on policy, would be ignored by closing administrators. Let's discuss, but I will start populating WP:DEFINING barring consensus on an alternative positive definition. Alansohn (talk) 12:19, 24 September 2009 (UTC)

I agree with the need for some definition of the word "defining". The above proposal though is too unclear for me to understand. Apart from that, I think we should just add this definition to WP:CAT, and no need to create a WP:DEFINING. We really don't need any more guidelines on Wikipedia... Debresser (talk) 12:33, 24 September 2009 (UTC)

WP:DEFINING would likely be a redirect to a paragraph within WP:CAT. Alansohn (talk) 12:42, 24 September 2009 (UTC)

The current situation is that some categories are forbidden by policy, but no categories are required by it. Categories aren't articles; they're a method of organizing articles. So they shouldn't be entitled to anywhere near the deference of an article regarding whether it should exist. Nor do most people desire the kind of mechanistic system you seem to want: a category should only be deleted if X policy expressly demands its deletion. That's not how this works at present, and I for one don't think it should work that way (or I'm at least skeptical that it would be a good thing). Categories should instead be more subject to the kind of editorial judgment that Wikipedia contributors have to make when they decide what content should or shouldn't be in an article, or where it should go in that article. That judgment is bounded by policy to be certain, but within the bounds of what policy permits is the capacity for groups of contributors to make decisions case-by-case, through discussion rather than automatic policy enforcement. We are not cops, robots, or umpires just calling balls and strikes.

That said... I'm not convinced that "definingness" is the standard everyone (or anyone) uses in every CFD situation, but it's a word that is often used here at least to address certain problems perceived in certain categories, and in that sense it is at least one of the established and accepted standards for evaluating a category. The meaning of the word of course has to start with the dictionary, and then fill that in based on observed practice and comments by participants.

To start, the standard rests upon the underlying premise that we can't allow every fact within every article to be categorized, and certainly not every intersection or combination of facts, because the significant categories would be swamped by the insignificant, particularly in the form of a flood of category tags on every article. So even among all the possible verifiable, NPOV categories that could be created, those categories should be limited by a stricter standard than what is permitted for article content: limited to the most important, significant, or "defining" of the subject and/or their notability. A corollary premise is that a category's "definingness" has to be viewed "categorically," by which I mean that a fact's significance is not established by its significance for certain individual members, but rather by its meaning for the group as a whole.

This discussion should proceed with those premises in mind. If those aren't agreed upon, then discussing what "defining" means is premature. Postdlf (talk) 20:38, 24 September 2009 (UTC)

(I do have some suggestions for the types of categories that may be presumptively "defining", but I want to make sure we're on common ground before we get into that). Postdlf (talk) 20:45, 24 September 2009 (UTC)

Defining tends to almost always apply to people categories. A little less so to other topics. Vegaswikian (talk) 23:01, 24 September 2009 (UTC)

Perhaps because people categories are created at a much greater (and reckless) pace? But I've also seen it a lot in relation to places. It's often an issue of a category reversing the proper relationship between two things, like categorizing a real place by the creative work that is set there ("Cities featured in Top Chef") rather than the creative work by where it is set, or the place by what landmarks are located there ("Cities with super-tall roller coasters") rather than the landmarks by where they are located. Years ago I saw Agriculture categorized by Category:Kansas; same issue. Postdlf (talk) 14:40, 25 September 2009 (UTC)

I'm also a little confused by Alansohn's proposal. So we would presume a category is defining, but this presumption could be rebutted by providing reasons that it is not. Isn't this essentially the equivalent of having a "negative" definition of "defining"? We're still not saying what it is, but we are saying what it is not. I happen to favour such an approach, but if I understand the proposal correctly the intent was to get away from negative definitions. Good Ol’factory ^(talk) 21:57, 24 September 2009 (UTC)

I fully agree with the underlying premise that we can't allow every fact within every article to be categorized, but I'd like to add, "even if sourced". I believe there is a misconception that we need to categorize anything and everything we can find a source for. Just because the Albuquerque Register prints that President Obama has athlete's foot doesn't mean we need Category:US Presidents with foot fungus. And that leads me to "defining". Obama isn't defined by having athlete's foot. He is defined by being President, having been a Senator, having lived in Illinois, etc. If asked to describe facts about someone, you're going to start with the big ticket items. That is what I mean when I say "defining". Loosely, those facts that would show up in the first paragraph of an article are what defines someone. --Kbdank71 15:14, 25 September 2009 (UTC)

If anything, there is a presumption that a particular fact is not defining of its subject(s). Most information is not, which is why we don't (and shouldn't) categorize most facts, even though verifiable and sourced. Postdlf (talk) 18:54, 28 September 2009 (UTC)

Can we add something that says basic facts should not be used for categorizing since they are generally not defining? Vegaswikian (talk) 20:01, 28 September 2009 (UTC)

The problem arises as to what a "basic fact" is. I would call birth year and death year "basic facts", but we do categorize them. Without actual examples of non-defining information being provided, we're not much closer because we leave interpretation entirely up to the reader. Good Ol’factory ^(talk) 21:43, 28 September 2009 (UTC)

[edit] Aid to navigation?

I, and most readers and probably most editors, believe that categories are an aid to navigation for the average user. I just happened to look at Category:Flora of Nevada and as an average reader, I find this of no navigational value. I accept the fact that for an expert in the field this probably is useful, but for the rest of the readership it is incomprehensible. Is this something that we should consider 'fixing'? Vegaswikian (talk) 22:07, 28 September 2009 (UTC)

I feel like I am an average user, and I _definitely_ find categories such as that one quite useful. What makes you think that most readers don't? Libcub (talk) 01:59, 29 September 2009 (UTC)

I also don't see the problem. Debresser (talk) 12:38, 7 October 2009 (UTC)

I'm becoming more sure that the problem is that, among reasonable people, there are very different expectations on what categories can do for you, and that some expectations are accepted, and others not. It is also a problem that some people see a problem, and others say they don't. --SmokeyJoe (talk) 12:47, 7 October 2009 (UTC)

That is not a problem. That is another way of saying that the previous editor hadn't eplained his "problem" (at all or insufficiently). Debresser (talk) 12:52, 7 October 2009 (UTC)

Debresser, I'd like to understand your reply, but at the moment, I don't. Are you saying that a problem is not a problem if it is not well explained? --SmokeyJoe (talk) 12:57, 7 October 2009 (UTC)

Not at all. I am saying that I don't know if there is a problem, because I don't understand what Vegaswikian sees as problematic, nor do I see any problems myself so far. Debresser (talk) 13:00, 7 October 2009 (UTC)

I don't know what Vegaswikian has in mind, but to me this category is of dubious value because (a) the plants' articles are titled with Latin names instead of common names (this isn't something we at categorization can do much about); but also (b) there is no explanation of what criteria are fulfilled by the plants in this category. I presume there are more than 167+14 species of plants in Nevada, right? Yet if we tried to put every plant species into a category "Flora of ..." for every state and country in which it grows, we would end up doing a vast amount of work and just get a huge mess as a result. Or are these plants which grow exclusively in Nevada? That would make more sense (though pretty unlikely). Anyway, the category (if it has a reason to exist at all) ought to be properly documented. That's how I see it anyway.--Kotniski (talk) 13:09, 7 October 2009 (UTC)

A good point. The oak is prevalent not only in Nevada. So it would be strange, if somebody were to add it to this category, even though it grows there. This category should perhaps be restricted to flora that is found only in Nevada (if such excists). What is going on in other "Flora of..." categories? Debresser (talk) 13:20, 7 October 2009 (UTC)

It seems they list all native flora, see Flora of the United States. Debresser (talk) 13:22, 7 October 2009 (UTC)

There certainly shouldn't be any categorization of plant or animal species by subnational political divisions, and probably not for national either, except for endemic species. House Mouse is in Category:Mammals of Michigan. That's completely ridiculous, and if the categorization were complete to cover every country and subnational state in which the house mouse can be found, the category tags would dwarf the actual article. All of the national flora and fauna categories should be renamed to "Endemic [fauna/flora] of Foo" and pruned accordingly, and all of the subnational flora and fauna should just be deleted. Lists by country/subnational entity are the only reasonable method by which to gather all the species found in a particular locale; above that, they should not be categorized any more specifically than by continent and/or region except for endemic species.

Are there any good arguments to the contrary? Postdlf (talk) 13:35, 7 October 2009 (UTC)

That makes sense to me.--Kotniski (talk) 13:42, 7 October 2009 (UTC)

House mouse a member of Category:Mammals of Michigan. :) Anyway, I agree as well. Just, do we need the word "endemic" here? It makes things sound so frightfull. Debresser (talk) 15:45, 7 October 2009 (UTC)

I agree also. Ideally all these categories would be related to purely geographical entities (continents, bodies of water, etc.), not political divisions of any type. Plants and animals aren't known for respecting political boundaries. --RL0919 (talk) 16:38, 7 October 2009 (UTC)

I took the first, small stab at cleaning up the structure. There are others that can be dealt with piecemeal like this (check out other subcategories of Category:Fauna of Michigan), but don't list them together because at this point they have separate issues. For a broader, systematic reworking, we should notify the relevant WikiProjects (Tree of Life, Mammals, etc.) and make sure they're on board, add a paragraph to WP:OCAT re: geographic distribution of species, and then start the mass renamings and deletions. Postdlf (talk) 17:03, 7 October 2009 (UTC)

That is exactly what should be done. And you are welcome to it. Debresser (talk) 18:01, 7 October 2009 (UTC)

Don't all volunteer at once now... Postdlf (talk) 18:13, 7 October 2009 (UTC)

I put in my !votes in support of the nominations you made. Based on previous experience, I would recommend making just a few nominations initially to see if there is any counterargument or other negative response. (Remember that relatively few people read this talk page.) Once a few have worked their way through the CfD process, we should know if it is reasonable to proceed further. --RL0919 (talk) 18:31, 7 October 2009 (UTC)

I'm starting with the weirdo ones that aren't part of a comprehensive system; I'll take up the others later after further discussion. Postdlf (talk) 20:12, 7 October 2009 (UTC)

[edit] DEFAULTSORT:Manure Management

I am puzzled why I start seeing numerous usages like {{DEFAULTSORT:Manure Management}} in Manure management. At first glance, I fail to see the corresponding rule. - Altenmann >t 17:22, 9 October 2009 (UTC)

It looks like it was added just from some kind of AWB quirk. There's no need to manually pipe-sort an article like this in categories because it will automatically be alphabetized by its title. Postdlf (talk) 17:29, 9 October 2009 (UTC)

But there's a difference between Manure Management and Manure management. Sort keys should have capitals for the first letter of each word (at least that's what it says in the guideline, though obviously if a different convention is used within a given category, then that's the convention to follow).--Kotniski (talk) 17:37, 9 October 2009 (UTC)

I don't see such guideline. What I see is "A case-insensitive sort can be achieved by following the convention that initial letters of words are capitalized in the sort key, but other letters are lower case. For example, use "Dubois" in sort keys rather than "DuBois"." I.e., it can (i.e., if required), rather than must. - Altenmann >t 23:48, 9 October 2009 (UTC)

What does that accomplish? Postdlf (talk) 18:04, 9 October 2009 (UTC)

It would accomplish case-insentitive alphabetization: (Big Bang, Big dick, Big Lie), rather than (Big Bang, Big Lie, Big dick). Notably, it will put side-by-side such pages as Good Morning and Good morning (bad example, but you get the idea). - Altenmann >t 23:43, 9 October 2009 (UTC)

I guess I'm surprised to learn that categories' alphabetical sorting is case-sensitive. It seems to me that, if anything, the situations in which we'd want case-sensitive sorting would be fewer than those in which we'd want case-insensitive sorting, so maybe the software should be changed? In fact, I can't even think of any examples in which case-sensitivity would be preferred; maybe with people names, but we have to manually pipe those anyway to sort by last names. Postdlf (talk) 15:09, 10 October 2009 (UTC)

Yep, the software should be changed - there's been a bug report at bugzilla for about 5 years, but our so-called developers haven't managed to solve the problem yet.--Kotniski (talk) 18:24, 10 October 2009 (UTC)

You don't see it in the guideline, because it has been taken out of the guideline, because it was disputed.

If the sole purpose is to achieve a case-insensitive sort, then the solution is to set an All-caps sort key. This would make it clear what is being done here, instead of leading to confusion in cases where capitalising the first letter of a word is simply wrong e.g. specific epithets. Hesperian 02:21, 10 October 2009 (UTC)

It is in the guideline, though rather hard to find, just above #Using sort keys. But "simply wrong" doesn't apply here - readers never see the sort key, so it doesn't matter whether it conforms to rules of English usage. This convention has the advantage that many article titles follow that pattern anyway, making it less often necessary to specify sort keys - the same could be argued of a convention of not using any capitals except for the first letter, but I see no reason to change.--Kotniski (talk) 08:14, 10 October 2009 (UTC)

[edit] Rank free articles

Rank free articles: I for one feel that the category importance scale should be abandoned. It is subjective and misleading. In my bid for rank free articles in Wikipedia - I give some examples of rank free proposals given in the biological literature, which relates to the way that Wikipedia ranks wildlife pages. Endangered species, for example, are more often than not rated with high importance (I think always). However, there is lots of published research arguing that a conservation focus directed solely on species level of biodiversity is a dangerous premise (e.g., [[2]]). It is true that endangered species are important - but for different reasons a common species could also be important, such as the ecological services it contributes over a broad geographic area. The keystone species concept is another example of this kind of ranking. Some conservationists try to highlight the great importance of one 'keystone' species over another. However, a critical examination of this concept by some of the biggest minds in conservation studies (Mills, L.S.; Soule, M.E.; Doak, D.F. (1993). "The Keystone-Species Concept in Ecology and Conservation". BioScience 43 (4): 219-224.) suggests that it be abandoned because it is not clear what constitutes a keystone species. The review shows that keystone species is used frequently without any data to back up the claim and it is not entirely clear what research could be used to make this kind of determination. This debate is also similar to those in taxonomy - where the 'new' approach is rank free taxonomy (e.g., [[3]]). I have found the importance scale in wikipedia articles a great source of frustration for this reason. There are different reasons why some species are important - but those reasons are not always clear, especially to a wiki editor. Hence, all the literature review on ranking in the biological literature suggests that this type of approach be abandoned. Although it has its supportors - I feel that the place for ranking does not belong in wikipedia. If this ranking scale of high to low importance continues to be used - we will find ourselves in a perpetual loop of debate over what is and what is not of high or low importance and most of the ranking will be irrelevant and totally misleading. External ranking needs to be abandoned so that the reader can make a personal determination of how important the article is. However, I am not opposed to giving some articles a high importance rank if it is more generally applicable to an entire sub-set of articles. Biology, Sustainability, Conservation biology, Ecology, and Evolution are examples of articles that should have high importance - but ranking a species of salamander over a toad as high versus low importance has no place in wikipedia. How do we fix this problem?Thompsma (talk) 22:59, 18 October 2009 (UTC)

[edit] Categories named after musicians

A while ago, there was a CFD in which several categories that shared a name with musicians were deleted. The rationale given for deletion by the original nominator was "overcategorization." There was no clear consensus in the original deletion discussion to keep or delete. But the closing admin stated simply "the result was delete" with no further explanation (a violation of WP:JUSTAVOTE). Following this outcome, a filed a deletion review in which I brought this up. Still, comments were evenly split. I always assumed that when there is a deletion discussion, and consensus cannot be reached, that it should default to keep/restore. I gave several reasons for keeping, most notably from this guideline:

Every Wikipedia article should belong to at least one category. Similarly every category (except Category:Contents, which is the root of the hierarchy) should be placed in at least one parent category.

Given this, in general, every musical artist for whom there are articles on at least several of their albums and at least several of their songs should have a category sharing their own name to serve as a parent category. Who agrees? Who disagrees? Shaliya waya (talk) 16:30, 25 October 2009 (UTC)

disagree. See WP:OC#EPONYMOUS. Good Ol’factory ^(talk) 20:54, 28 October 2009 (UTC)

[edit] One-item category?

Is there any policy regarding categories containing only one item? I can imagine the potential for expansion plays a role, but having only one applicable item in the meantime doesn't seem to warrant such a navigational tool or look like much else than overcategorization. Mbinebri ^{talk ←} 23:30, 25 October 2009 (UTC)

Where this single-item category is part of a wider scheme of categorisation then it is usually fine. The applicable policy, WP:OCAT#Small_with_no_potential_for_growth, will allow for categories which are "...part of a large overall accepted sub-categorization scheme". cf Category:Flags of Nepal which, as part of Category:Flags by country, has survived Cfd a couple of times now.

Xdamr^talk 23:52, 25 October 2009 (UTC)

I can see why the Flags of Nepal would stay, but what I was referring to isn't part of a larger scheme. To be more specific, I was asking this question in relation to a category created to house an artist's one album. It seems like overcategorization to me to create a category for a topic with nothing to navigate between. I was thinking there might be a policy saying in such an instance the category should wait to be created until there's use for it (i.e., at least two items to include in it). Mbinebri ^{talk ←} 02:58, 26 October 2009 (UTC)

Yes There is consensus to retain all "X albums" categories, even if they only have one member. For right now, I guess you'll have to take my word for it, as I do not have a citation immediately available. —Justin (koavf)❤T☮C☺M☯ 21:18, 28 October 2009 (UTC)

[edit] Hard redirects

The RFC on switching to hard redirects is now open; please see WP:Hard category redirects and discuss on that talk page.--Kotniski (talk) 08:47, 26 October 2009 (UTC)

[edit] Question

Koavf and I would like to know if adding Category:Monotheistic religions to Yazidi would be redundant because Category:Yazidi is already a subcategory of Monotheistic religions, or if this would be relevant because of it being a distinct subcategory as by the Wikipedia:Cat#Duplicate_categorization_rule? Debresser (talk) 20:33, 28 October 2009 (UTC)

The same question would be relevant for Christianity and Bahá'í Faith inter alteres (with their respective categories, of course). Debresser (talk) 20:36, 28 October 2009 (UTC)

Wikipedia:Cat#Eponymous categories seems to apply: "an article should not be excluded from any list category on the grounds that its eponymous category is made a 'subcategory' of that category."

What is a "list" category? Debresser (talk) 20:53, 28 October 2009 (UTC)

It says at the start of the guideline. It's a category that lists items of a particular type (so "religions" in this case), as opposed to items related to a particular topic.--Kotniski (talk) 20:54, 28 October 2009 (UTC)

My take It is not clear to me if (e.g.) Christianity belongs in Category:Monotheistic religions, or if Category:Christianity belongs in it, or both. Am I just dense? —Justin (koavf)❤T☮C☺M☯ 21:13, 28 October 2009 (UTC)

My understanding of the guideline is that both the article and the category could be part of Category:Monotheistic religions (provided, of course, that Christianity is considered to be monotheistic, which is the consensus in the article currently). --RL0919 (talk) 21:41, 28 October 2009 (UTC)

Yep. Debresser (talk) 21:46, 28 October 2009 (UTC)

"List category" is an ambiguous name, because we have categories for "List of..." articles. Debresser (talk) 21:47, 28 October 2009 (UTC)

[edit] Should all members of a distinguished category be a subset of the parent category ?

From wp:categorization# Subcategorization it isn't clear if all or just some the page members of a distinguished category are supposed to be a subset of the page members of the parent category. Which is it, all or some? Also, could I have a couple of content category examples of the "perfect" or "ideal" distinguished category? Maybe I can glean the answer from the examples and learn some other things about content categories in general. Pknkly (talk) 05:20, 29 October 2009 (UTC)

In theory, yes. In practice, we're a very, very long way from it. Category:Utah is in Category:States of the United States. Not everything in Category:Utah is a state. This problem could be fixed, by putting the article Utah into Category:States of the United States, and putting Category:Utah into something like Category:United States topics by state. Is it worth the trouble? Hesperian 05:47, 29 October 2009 (UTC)

Again, this is covered by the eponymous categories section (indeed the article on Utah should be put into the category). Since these matters are causing so much confusion, it seems we have to try rewriting the guideline again to make everything finally clear.--Kotniski (talk) 09:03, 29 October 2009 (UTC)

Hear, hear. Debresser (talk) 09:29, 29 October 2009 (UTC)

That's not a "problem", because no one should expect Category:Utah to contain more states, unless it were called something like "Utah states." Obviously Category:Utah contains Utah-related articles and categories. postdlf (talk) 12:07, 29 October 2009 (UTC)

[edit] The term "list category"

We really, really need to do something about the term "list category" in this guideline, as it causes endless confusion with the concept of "category of lists". In the discussions and RFC on eponymous categories this summer, this was very clear; I just noticed that there was a late answer at Talk:Saskatchewan#Category:Provinces and territories of Canada vs. Category:Saskatchewan, the discussion that initiated the RFC in the first place, which even more clearly shows the confusion. I also see here that Debresser commented on the same thing yesterday. The term needs to be changed to avoid further confusion. "Set category" would be most logical, but I doubt most people would think of a set as in mathematics; perhaps "collection category", "item category", "membership category"? I'm sure someone has a better suggestion, but "list category" must go. —JAO • T • C 10:04, 29 October 2009 (UTC)

"Set category" works for me. But then, I'm an old mathematician. What about "group category"? Debresser (talk) 10:42, 29 October 2009 (UTC)

Yes, either works for me. Another term I've seen used in this sense is "index category". (We could also do with better terms for "distinguished" and "non-distinguished" subcategories - would "non-diffusing" and "diffusing" be any better? They seem slightly more meaningful.)--Kotniski (talk) 11:12, 29 October 2009 (UTC)

That is even more confusing. Debresser (talk) 11:49, 29 October 2009 (UTC)

I like "index category" as a replacement for "list category". If we make a change like that, we should be sure to catch it everywhere it appears, or it will cause even greater confusion. --RL0919 (talk) 13:15, 29 October 2009 (UTC)

What about "series"/"group" category, to indicate that it contains multiples of similar things—members of a series or group, as opposed to a "topic" category, which contains subtopics related to a singular thing. The distinction should be clear from the category's name: plural versus singular titling. Category:European countries is a group of countries; Category:Europe is a topic with subtopics. Subcategory members of a group category may in turn be further subgroupings, or topics in their own right; and subcategories of a topic category may also be subtopics that are singular topics or groups themselves. postdlf (talk) 13:53, 29 October 2009 (UTC)

Ok. 3-0 in favor of "group category". Now the relevant Wikipedia pages should be updated with the proper definitions and the right term in the right place. Debresser (talk) 14:31, 29 October 2009 (UTC)

Actually I said I liked "index category". But I'm fine with "group category" as well. As to pages to update, it appears that in addition to WP:CAT, updates would be needed for WP:FAQ/Categorization and WP:FAQ/Categories (and possibly others, since I have not done an exhaustive review). --RL0919 (talk) 14:46, 29 October 2009 (UTC)

I like both "index" and "group" as well. Great development on this! Thanks all, —JAO • T • C 14:54, 29 October 2009 (UTC)

I think it is a reasonable change -- but I don't think less than a day of discussion and agreement by a small number of participants is a warrant to implement the change yet. The confusion has been there for a long time, there's no need to rush. older ≠ wiser 14:57, 29 October 2009 (UTC)

I dunno. "group" is too generic. Techincally all categories group articles. I think what is trying to be conveyed is that it's a group of nouns which are of type x, rather than a group of nouns which fall under a certain topic. It would seem a rather fine distinction, depending on how it's phrased.

This is a good point. Categories by function "group" and "list". So, we may be jumping from one bad reference, "list", to another, "group". "Group" may be just as difficult to grasp as is "list" for the same reason - categories already "group". Pknkly (talk) 17:18, 30 October 2009 (UTC)

How about "grouped by topic" and "grouped by sub-type"? - jc37 15:27, 29 October 2009 (UTC)

Well, how about adapting those for brevity: "topic category" (as now) vs. "type category" (instead of list category). Thoughts?--Kotniski (talk) 10:39, 30 October 2009 (UTC)

That conveys precisely the opposite "all topic-related articles". I stick to "group category", and do not agree with jc37 who thinks that is too generic. Debresser (talk) 12:20, 30 October 2009 (UTC)

I think "group" is too generic (see above)).Pknkly (talk) 17:18, 30 October 2009 (UTC)

Suggest Subject category - I was just looking at list categories where it seems to say that "list categories" are "subject categories". So, why not make them a "subject category". I liked the advise given above by one of the editors about using nouns. Stay away from verbs or words that may be interpreted as verbs (e.g., group, index, list), especially verbs that describe what a category already does. If we use "subject categories" it would compliment "topic categories". Pknkly (talk) 17:18, 30 October 2009 (UTC)

Unconvinced - I think for most people "subject" and "topic" are synonyms, so having those two terms in opposition would be confusing.--Kotniski (talk) 17:52, 30 October 2009 (UTC)

[edit] Speedy criterion #6

Where did speedy criterion #6 come from? Debresser (talk) 11:48, 29 October 2009 (UTC)

If I recall correctly, it grew out of some repeatedly repetitious full discussions on if and when to disambiguate "Georgia" in category names. After probably dozens of discussions, I think someone proposed a general rule here or on the CfD talk page, which was supported by consensus, that disambiguations should be consistent throughout a parent–subcategory heirarchy regardless of the context of the rest of the category name. In part it was thought to be a good thing in that it would bring predictability and consistency to the naming conventions for categories. It's probably at least a year old now; I can't remember exactly when it was adopted. Good Ol’factory ^(talk) 21:05, 29 October 2009 (UTC)

Thanks. I didn't notice it till after the edits two days ago. If so, then much of the present discussions at Cfd is redundant. Actually, I've been wanting to say for a while that now that we have more participants, we also have more nominations on a daily basis. It is a good thing we should start using #4 and #6 more extensively. Debresser (talk) 21:59, 29 October 2009 (UTC)

Which discussions are redundant? We can probably just process them after two days if they have attracted no opposition. (But note that it only applies if the eponymous parent category is disambiguated; it does not apply if only the corresponding article is disambiguated but not a parent category.) Good Ol’factory ^(talk) 07:35, 30 October 2009 (UTC)

Ah, so there's a reason for the strange naming of Category:Georgia (country) at the Olympics, on which I once commented on its talk page. It still feels very funny though... —JAO • T • C 07:29, 30 October 2009 (UTC)

All those song and band names, no? Debresser (talk) 10:28, 30 October 2009 (UTC)

The ones I nominated were eponymous categories themselves, so it wouldn't apply to those. If those are renamed, though, then their subcategories for songs, albums, etc. would be eligible. Good Ol’factory ^(talk) 00:36, 2 November 2009 (UTC)

I see. It is all very confusing. Debresser (talk) 03:55, 2 November 2009 (UTC)

Couldn't No.6 now be regarded as being redundant to No.4? This would after all be a "...rename bringing a category or categories into line with established naming conventions for that category tree."? (a standard disambiguator could after all be considered a 'convention', even if that is not the traditional way we have interpreted No.4) Or is this being a little too expansive?

Xdamr^talk 04:00, 2 November 2009 (UTC)

In my opinion that would be too freely an interpretation of #4. Even I never intended such. Debresser (talk) 04:04, 2 November 2009 (UTC)

Probably best. --Xdamr^talk 04:14, 2 November 2009 (UTC)

[edit] Template:CatDiffuse

{{CatDiffuse}} has been nominated for deletion. See WP:TFD at Wikipedia:Templates for discussion/Log/2009 October 28

70.29.209.91 (talk) 19:12, 29 October 2009 (UTC)

The result of the deletion discussion was keep.

--David Göthberg (talk) 03:40, 20 November 2009 (UTC)

[edit] Category:Pairs

The just-created Category:Pairs contains Crime and Punishment, Fire and Ice, Religion and politics, and more. Is this a helpful category? Is this the right place to ask, or am I supposed to make up my own mind and take it to WP:CFD? Johnuniq (talk) 08:59, 3 November 2009 (UTC)

Probably best to take it to CFD. Doesn't sound a very helpful category to me, but some people might have different opinions.--Kotniski (talk) 09:21, 3 November 2009 (UTC)

I agree that it should be discussed at CfD. (In the meantime, I had to add pork and beans: scandalously not included.) Good Ol’factory ^(talk) 09:54, 3 November 2009 (UTC)

As can be seen by the red link above, the user who created the category asked for it to be deleted, and it's all cleaned up. Johnuniq (talk) 21:00, 3 November 2009 (UTC)

[edit] People from [Location] categories

Inclusion criteria What are the criteria by which a category of the sort (e.g.) Category:People from Chicago, Illinois may be added to an article? That article reads "The following people were born in, residents of, or otherwise closely associated with the city of Chicago and its surrounding metropolitan area." Is this normative for other such categories? Can someone point me to a policy/guideline/consensus about this matter? Thanks. —Justin (koavf)❤T☮C☺M☯ 02:54, 5 November 2009 (UTC)

Though "from" is such a wishy-washy word that just about any connection merits inclusion in practice, there should still be accuracy. An easy solution is that you remove any location category from an article that doesn't bother to mention it.

But the problem is that when the location categories are cut so finely as a single city, it's likely that they are going to be "from" multiple intersecting places given the patchwork of separate municipalities that make up most metropolitan areas. Particularly when we're dealing with notable, accomplished people, people's lives don't limit themselves to municipal boundaries (and there are even a smattering of neighborhood categories!). Where was I "from" during the two years that I lived in Arlington, VA, went to school in D.C., hung out in Alexandria, VA, and dated someone in Silver Springs, MD? All in a day's commute. If I merited an article, I'd have ten "from" categories just for where I've lived in my not-so-long lifetime. Plus probably another for my birthplace, where I never even lived. Which is one of the main reasons I really detest subnational people categories and wish they'd all be listified, but I'm unfortunately alone in that understanding. One step towards controlling it would be to categorize at no finer a level than a metropolitan area, which would address your problem here too. postdlf (talk) 18:55, 5 November 2009 (UTC)

If a normative category doesn't exist then a template for creating content category pages entitled "People from (city),(state)" should be created. It could include narrative as required by wp:Categorization#Category description. The template would automatically use narrative similar to the one used by Chicago, but it would stay clear of vague terms or phrases such as "otherwise closely associated". It should use examples and let people know what not to include within in. A clear narrative about what should be included and what should be exuded would support Postdlf's suggestion of pulling the category from articles that do not clearly mention, with a good citation, the criteria given within the narrative of the category. Pknkly (talk) 07:48, 6 November 2009 (UTC)

In my experience, the only truly effective way to change or narrow a category's inclusion criteria is by renaming it. Category tags can be added by people who have never even bothered to look at the category's description page, so if the limitation is not obvious from the name it will generally get ignored. postdlf (talk) 16:41, 6 November 2009 (UTC)

[edit] Eliminate or otherwise adjust speedy rename criterion #6

There is an ongoing village pump discussion about this here. Good Ol’factory ^(talk) 21:27, 5 November 2009 (UTC)

[edit] Quick summary edits

An edit summary for paragraphs 2/3 and 3/3 of the Quick summary section:

Moved the sentence A category page is a page in the Category: namespace. to the 3rd paragraph to tie in with the idea of the :colon prefix. That also gives us a chance to re-iterate that the links do not appear, which is worthy of repetition because it is a unique characteristic of the topic and needs to be learned by the reader.
Removed the sentence The target of this link is a page called "Category:Name", and to retain audience level, I created a link to what wikilinking is, by substituting the word "Including" (paragraph one, word one) with "Linking".
Included the concepts of what links here and rendering in the second and third paragraphs.

The minor changes are suitable for correction without the need to revert the multi-paragraph copy edit. — Cpiral Cpiral 00:51, 19 November 2009 (UTC)

[edit] Attention: Template:This is a redirect has been Nominated for deletion

Please see: Wikipedia:Templates_for_discussion/Log/2009_November_15#Template:This_is_a_redirect for a Tfd discussion related to this WikiProject. (related to the above notification)

Not positive I have the terminology correct, but believe this is whats called a 'meta-template', a template used to create other templates. The template: Template:This is a redirect was created by User:Lenoxus, a member of the Wiki_Redirect project. The template allows easily creating a specific template used to put TYPE redirects into a specific redirect category - "redirect of TYPE", e.g. "schools" and "hospitals", or "from alternative spelling" and "from alternative name". Categorizing redirects may also serve to facilitate disambiguation.

Template:This is a redirect directly supports intentionally entering the disambiguation categories indicated on the disambiguation guideline, which as a new editor here, I find straightforward. This approach both prevents overcategorization, but does not auto-categorize. -MornMore (talk) 02:54, 20 November 2009 (UTC)

[edit] Templates that auto-categorize

Feedback wanted from anyone interested in template programming and categorization.

Some templates add categories to the pages they are used on. This unfortunately also means they usually add categories to pages where they are only tested or demonstrated. So we have a how-to guide about how to avoid this problem. And some templates also need to use different categories in different namespaces, which can be tricky to do. So now we have made a meta-template that will make it much easier to handle categorization in templates. Here's the relevant links:

{{cat handler}} – The new template. We'd like some feedback on this template and its documentation before we deploy it. Comments and questions are very welcome on its talk page.
Wikipedia:Category suppression – The how-to guide. There's a discussion on its talk page about which parameters we should standardise for category suppression, more comments would be welcome there. By the way, some of the methods in that guide will probably become outdated once we deploy the above template.
Wikipedia:WikiProject Category Suppression – Personally I think a WikiProject for only category suppression is a bit overkill, but the project is going to widen its scope so perhaps it is okay. See its talk page.

Oh, and please don't start a discussion here, instead use the talk pages of the above pages.

--David Göthberg (talk) 03:43, 20 November 2009 (UTC)

[edit] "Approximate" acyclic directed graph

I'm curious: How can a graph contain "approximately" no cycles? I thought "The category system" is intended to describe the desired state of affairs, rather than the "impurities" due manual labor. Spill paint over the hood of a Ferrari, and you still have a Ferrari. BTW, finding cycles looks like a job for CatBot. Regards, Paradoctor (talk) 20:58, 20 November 2009 (UTC)

I agree. The category system is acyclic and directed. Cycles indicate errors, or at least suboptimally muddy thinking. Here, therefore, we should described it as directed and acyclic. Hesperian 05:47, 21 November 2009 (UTC)

Well, I agree that's how it should be, but we can't claim that it is. Many people put categories into other categories just because there's some relation between them, not because one's actually a subcategory of the other (eponymous categories being the most obvious example). If we want to ensure there are no cycles, we must make a rule that the subcategory relationship is really a subcategory relationship, and that will upset a lot of the categorization schemes currently in use (and so will doubtless run into opposition).--Kotniski (talk) 11:42, 21 November 2009 (UTC)

We can't claim that it is, no, but I think we can safely claim that it is best practice; which is surely the purpose of this page. Hesperian 11:50, 21 November 2009 (UTC)

Well, all right, try it and see if people object. (Many people don't object explicitly but would nevertheless object to the consequences, because they don't really get it.)--Kotniski (talk) 12:12, 21 November 2009 (UTC)

I'm not sure I understand what you mean. Are you saying that some categorization schemes currently in use contain cycles by design?

I finally found out what has been bugging me: "Acyclic directed graph" is too general, the category system has the same structure as a DAWG. Paradoctor (talk) 13:20, 21 November 2009 (UTC)

Actually, it is a concept lattice. Hesperian 13:40, 21 November 2009 (UTC)

For what the guideline used to say some time ago, see the old version of the guideline (the section "Cycles should usually be avoided"). When I rewrote the page I took the passage out because it seemed to be a lot of words saying nothing (it first says that we don't like cycles, but then goes on to say that some cycles - no particular clue as to which - are acceptable). I mentioned it at talk at the time and no-one commented, but if anyone wants to belatedly reinsert that passage now, so we can perhaps work on changing it to say something more useful, then that would be fine.--Kotniski (talk) 15:09, 21 November 2009 (UTC)

Question: Would Category:Categories that do not contain themselves contain itself?

Seriously, let's declare cycles to be the epitomy of evil. Either the text will stand, or someone will come up with a cogent counter-example. Win-win. Hesperian 11:32, 22 November 2009 (UTC)

Erm, what are "meta-fields"? Judging from the text, the only acceptable loops seem to be trivial self-references of a category to itself. I'm not sure I understand the use of that. Anyway, since cycles are generally considered a bad thing, this should be explicitly mentioned on the page among the "Things to avoid". There is a problem, though: I don't think there is a way for editors to determine whether a bad cycle exists, other than by manually checking. That's tedious at best, error-prone, and not necessary. As sugggested in my initial remark, there should be a tool that detects cycles, so contributors can diagnose such a problem, and identify affected categories. This is important, as creation of cycles is the result of uncoordinated collaboration. Regards, Paradoctor (talk) 15:52, 21 November 2009 (UTC)

_{edit conflicts are fun |-()}Oy, I noticed two more: "form a hierarchical structure, consisting in effect of overlapping trees". In a hierarchy, all elements are comparable wrt level. Here's a subgraph, which can (and presumably does) exist in the category graph: A>B>C & A>D>E>C. Is B on the same "level" as D, E, both, or none? Furthermore, "overlapping trees" does not specify how the trees overlap, allowing the possibility of different roots.

I suggest we reformulate the intro thusly:

"Wikipedia's categories resemble a rooted tree, the difference being that subtrees may overlap.",

and drop the technical stuff about DAGs/DAWGs/CLs/whatever in the second sentence, or stuff it into a footnote. This is a guideline, not a course in graph theory. ;) Paradoctor (talk) 15:52, 21 November 2009 (UTC)

It does not in any way resemble a rooted tree. It is a lattice, which is completely different. Saying it is like a tree will only confuse people.

And even if we were going to go down a "They resemble a tree except..." line, it would be must easier to understand if you phrased the exception as the logically equivalent "the difference being that categories may have more than one parent category". Hesperian 11:32, 22 November 2009 (UTC)

I don't see where the second extremal element required for a lattice comes from, there is no "bottom" category corresponding to the other extremal element required for a lattice. Neither is it a lattice graph, except in the trivial sense of choosing a sufficiently high-dimensional lattice.

As regards "logically equivalent", I agree. But if it is equivalent, what makes it better? This is an expositional text, which is read mostly by people who do not share our specialist knowledge, and are mostly interested in how-to instructions. Actually, the tree metaphor is slightly misleading, maybe "bush whose branches may rejoin" conjures a more appropriate image. A diagram might be helpful here. Regards, Paradoctor (talk) 13:46, 22 November 2009 (UTC)

Well, I'm afraid I'm out of my depth now as far as the graph theory goes... "Directed acyclic graph" I could understand - can you explain why that's not the appropriate technical description? And isn't something like "set of overlapping trees" an appropriate description for the intelligent non-specialist?--Kotniski (talk) 15:50, 22 November 2009 (UTC)

To say it's a DAG is not wrong, it's just too general. It's like describing your car by saying "it's a Volkswagen". Ok, but is it a Lupo or a Constellation? With a general DAG, clicking the parent categories of a category repeatedly will lead you to different roots depending on your choices along the way. With our system, you'll always end at the same node, category:contents in our case. That's because every category must be in another category (except the root, of course). I have not yet found a proper name within graph theory for this type of graph, so rooted tree with overlapping subtrees is the best description I can come up with. The problem with the "overlapping trees" is the same as with DAGs, it is not clear that there is a common root. HTH, Paradoctor (talk) 17:19, 22 November 2009 (UTC)

Right, I see. So what about "rooted directed acyclic graph"? And "set of overlapping trees with a common root" for the second audience (though there it's not necessary to be so precise).--Kotniski (talk) 17:27, 22 November 2009 (UTC)

Errm, what you call the "second" audience is actually the one this guideline is written for. Imagine an art historian reading "rooted directed acyclic graph". She/He might understanded the sense of "rooted" used here, and can probably manage to clear "directed", but I think "acyclic" is where the fast forwarding will begin. As I said, as a footnote I have no problem with whatever precision you care for, but the "second" audience is the one we work for. If you'd like a few numbers, check out the traffic stats for the article page and the talk page, you'll see that the traffic differs a factor of ~20. This means that hundreds of people view the article each day, of which the vast majority doesn't know and care less about DAGs, rooted or not. ;) Paradoctor (talk) 18:11, 22 November 2009 (UTC)

Well yes, I'd agree with that... So to rephrase, is "rooted directed acyclic graph" OK as the description we give for the specialist (minority) audience, and is "set of overlapping trees with a common root" a good enough description for the majority audience?--Kotniski (talk) 18:22, 22 November 2009 (UTC)

Can't speak for anybody else, but my vote is o|‾|_ <utter, complete and total submission> Paradoctor (talk) 20:07, 22 November 2009 (UTC)

The people we are writing this for aren't going to care about the global structure. The number of root nodes is irrelevant because it does not affect them. It doesn't even affect me, and I've been working in categories for years. The people we are writing this for are going to care about local structure: how the category system looks close up. All that matters is that any given category can contain multiple categories, and can itself be contained within multiple categories. At this scale, the structure of our category system looks nothing like a tree, and it is only after deep consideration that ones recognise "set of overlapping trees" as an accurate description. Hesperian 23:45, 22 November 2009 (UTC)