Wikipedia talk:Lists of lists

List-of-list categories
The guideline says that every list-of-lists should have a matching category, which seems reasonable. A category is easy to maintain, and if the list of lists is just an alphabetic list of the category entries, the list probably is not needed. Demanding a matching category means the list should be more than just an alphabetic list: it should have some structure, some added information. That said, the great majority of lists of lists do not have a matching category. With the large lists, creating and populating a category would take a fair amount of work. With the small lists like Lists of places in Sussex, two or three entries, the category would be at risk of being deleted. Any thoughts on softening the "should have a category" rule? Aymatth2 (talk) 02:31, 15 November 2019 (UTC)
 * Just drop this requirement. We might phrase it as "list-of-lists may have a matching category" but that would be rather meaningless as a guideline. Marcocapelle (talk) 20:26, 15 November 2019 (UTC)
 * That seems a bit extreme. The statement "Lists of lists should also be available as alphabetical categories" in Stand-alone lists dates back at least ten years. Removing it would have to be agreed at Stand-alone lists. This essay should expand and clarify but not contradict the guideline. I took a shot at defining an exception with Lists of lists. Aymatth2 (talk) 13:38, 16 November 2019 (UTC)
 * Note that removing the requirement does not necessarily imply that these categories should not exist. Marcocapelle (talk) 08:13, 17 November 2019 (UTC)
 * Dropping it should be agreed at Wikipedia talk:Stand-alone lists. I am undecided.
 * The "better" lists, meaning the ones with clean format, structure, categorization etc., tend to have matching categories. E.g. most of Category:Lists of film lists or Category:Lists of astronomy lists.
 * There are about 340 lists-of-lists with no matching category. A lot of them are very short and/or questionable lists like Lists of airports in Timor.
 * It would be easy to add matching categories for shortish lists like Lists of disasters in Indonesia.
 * I do not have a good feel for how many longer lists-of-lists would be left if we cleaned up the short ones or converted them to disambiguation pages.
 * Either way, the guideline should say that a matching category is good practice for all but very short lists-of-lists, and explain why: basically that the list-of-lists and the category can be cross-checked. This is an arcane subject, but since we have these lists, they should be organized as well as possible. Aymatth2 (talk) 11:48, 17 November 2019 (UTC)


 * I think a softening is a good idea. I like the exception you added at . I think a reasonable approach in these situations is to go down one level of abstraction, so to speak. So instead of categorizing Lists of opera companies in Category:Lists of opera companies, just categorize it in Category:Opera companies. In this particular case, I think it would be clean to use a " " sortkey for the LoL, and sort the linked lists (e.g. List of North American opera companies) with "*". Though that scheme might not work for all examples. Colin M (talk) 00:25, 19 November 2019 (UTC)
 * I like that a lot. I have taken a shot at wording it in . Assuming there are just two or three lists, it seems simpler to just give them all blank sort keys.
 * I have been plugging away at Category:Lists of lists with no matching category and have got it down to 253 entries. I will probably keep going. Mostly it is easy to either find a category or make one and populate it. But I have an uncomfortable feeling that there are a lot of lists-of-lists like Lists of airlines that have not been categorized as such. Aymatth2 (talk) 08:42, 19 November 2019 (UTC)


 * User:DexDor notes at User talk:Aymatth2 that with Lists of Olympic medalists in handball, the men and women sub-lists are already in Category:Handball at the Summer Olympics. Adding the list-of-lists to the category just clutters it up. The list-of-lists does not give any information other than the names of the two sub-lists and is not the target of a link from any other page. Should it be made into a disambiguation page, or perhaps just deleted? Aymatth2 (talk) 12:20, 20 November 2019 (UTC)
 * Ooh, yeah, that's a tricky case. I've come across several examples of this specific genre of page that splits/disambiguates two lists of athletes by gender. Other examples:
 * Lists of Olympic medalists in swimming
 * List of University of Florida basketball players
 * List of European Athletics Indoor Championships medalists
 * I guess the first question to be asked is: is it plausible an editor would want to intentionally link to one of these from an article? List of European Athletics Indoor Championships medalists is the only one of these 4 examples that has a single mainspace link, and it looks like it dates to a time when the target of the link was a single stand-alone list, rather than the DAB/LoL that's there now. I think it's unlikely. If both male and female medalists are relevant in context, you might as well just link to the two articles separately, rather than linking to the pseudo-dab. That's what's done in templates like Swimming at the Summer Olympics and Olympic medalists.
 * This would suggest they should either be marked as DABs or deleted. I guess the deciding factor between those outcomes is: is something like "List of Olympic medalists in swimming" a plausible search term? I don't really have an opinion on this. So I'd support either deleting these or converting into DAB pages. DABifying is probably the path of least resistance. Colin M (talk) 20:10, 21 November 2019 (UTC)
 * I agree (delete or dab). At least one of these pages has previously been a dab page. Editors keep coming across these pages (for example because they appear in lists of orphaned articles or short non-stubs) and changing them so delete may be a better option in the long term. In the (unlikely) event that a reader puts that title into the search box let the search function do the job of suggesting suitable pages. DexDor(talk) 20:39, 21 November 2019 (UTC)
 * I have seen sports-lists like these, also geographic like east/west and historical like pre-/post-independence. They have negative value as search terms, because they clutter up the results list. If Lists of Olympic medalists in handball did not exist, the first results in a search on that term would be List of Olympic medalists in handball (men) and List of Olympic medalists in handball (women). Quicker if the reader does not click on the lists of lists.
 * Almost always a link to a list-of-lists will be a "see also" type of link, where there would be no problem linking directly to the articles in the list.
 * At risk of introducing a red herring, I did a search on "Lists of Olympic medalists in swimming" and got Lists of Olympic medalists in swimming, Lists of Olympic medalists, List of Olympic medalists in swimming (men), List of Olympic medalists in swimming (women), List of top Olympic gold medalists in swimming, List of Olympic medalists in synchronized swimming, List of Australian Olympic medallists in swimming and further down List of individual gold medalists in swimming at the Olympics and World Aquatics Championships (men). So this one may actually be a valid list+category.
 * I will take a shot at rewording to say something like "consider treating as a disambiguation page". Aymatth2 (talk) 21:02, 21 November 2019 (UTC)
 * Another factor in favour of deletion is that LoL pages that are explicitly lists of articles duplicate the category system - e.g. compare Lists of disasters in Indonesia and Category:Lists of disasters in Indonesia. DexDor(talk) 21:06, 21 November 2019 (UTC)
 * The essay says that, maybe not prominently enough: "If the list-of-lists article does no more than show the same lists in the same alphabetical sequence as the list-of-lists category, it is questionable whether it has a valid purpose. A useful list-of-lists article will normally present the lists in a more structured form than is possible with a category and/or provide more information than just the names of the lists." In reality, a lot of the list-of-lists articles just repeat the matching category, or (worse) a subset of the category. Aymatth2 (talk) 22:45, 21 November 2019 (UTC)

Should a stand-alone list that's been split into multiple articles due to size be considered a list of lists?
Or, more generally, any article that serves as an index to multiple list articles which, together, partition one logical list (by year, alphabetically, by country, etc.), and which could reasonably all go in one article if not for size concerns? Just a few examples:
 * Lists of bisexual people
 * List of former Maryland state highways
 * List of violent incidents in the Israeli–Palestinian conflict, 2015
 * Lists of Empire ships
 * Lists of Padma Bhushan award recipients

Structurally, these articles are lists of lists, but semantically they really just represent a single list, no?

They're very different from articles like Lists of battles, Lists of books, Lists of highest points, Lists of English words etc. I would consider these ones the "true" lists of lists. By design, they do not partition their domain. There will likely be overlaps (e.g. books that are listed in multiple lists in Lists of books) and gaps (e.g. books that aren't listed in any of the Lists of books lists). They're presenting the reader with a variety of subsets of the domain according to different criteria.

I think these groups are very different, and advice that applies to one will not necessarily apply to the other. For example, split-long-lists are unlikely to have a corresponding "Lists of..." category, whereas the true lists of lists will (or should) always have one. Another example is naming. A "true" LoL should have a name of the form "Lists of X", or "List of lists of X", whereas a split-long-list makes more sense at a singular "List of X" title.

What if this page (and Category:Lists of lists) dealt only with true lists of lists, and split-long-lists were dealt with in a separate page? WP:NCLONGLIST would be a good starting point - it's nominally a naming guideline, though it already talks about more than naming.

I realize this would be a major change, but I just wanted to throw it out there as an idea.

Also, there is the mirror image possibility: is it possible to have pages which semantically are lists of lists, but structurally are confined to a single article? You could argue that something like List of films considered the best is an example, since it consists of several loosely-related, overlapping (embedded) lists i.e. "List of films considered the best by critics", "List of films considered the best by genre", "List of films voted as the best in national polls". Would it be helpful to readers to rename it "Lists of films considered the best", and to categorize it in Category:Lists of film lists? I'm more ambivalent about this. Colin M (talk) 23:43, 21 November 2019 (UTC) — SMcCandlish ☏ ¢ 😼  10:57, 22 November 2019 (UTC)
 * Related: MOS:GLOSSARY (a proposed guideline) has some advice on splitting long glossary articles. They say the original base title should either redirect to the first article in the split or it should be turned into a "disambiguation page, with a full lead, and links to all the chunks." I was only really able to find one glossary that's been split: Glossary of education terms. There's also Glossary of baseball which is a full listing which, under the hood, transcludes a bunch of sub-glossary articles like Glossary of baseball (A) etc. Yikes.
 * WP:NCLONGLIST seems to favour the "redirect to the first article in the split" approach, though that seems contrary to current actual practice. User:SMcCandlish started a discussion thread on the talk page suggesting some text to more strongly discourage "master" pages linking to each sub-article following a split, but nothing came of it. That Dec. 2017 thread was the last edit on the talk page, and the last time there was a non-trivial edit to WP:NCLONGLIST, so I get the sense that it's kind of a dead policy page... Colin M (talk) 00:11, 22 November 2019 (UTC)
 * Or a really stable one. :-) I agree with "Structurally, these articles are lists of lists, but semantically they really just represent a single list", i.e., they aren't lists of lists in any sense we care about. That's part of why the base title should redirect to the first page in a split series rather than go to a pretty much content-free "master list" page that is basically a combination of a disambiguation page and a list of lists.  Those intermediary pages just really don't serve any reader-facing purpose, and are an impediment to getting to the actual content. The only reason split lists exist is technical, at least in a broad sense of that word: article-length limits exist to avoid slowing or crashing browsers or getting only a partial load into the editing window,  to avoid alleged bogging down of the human head receiving the content. The latter is a subjective and questionable concern, and it comes at significant costs, like inability to do an in-page search of the entire content of the list, and editorial hassles like citations breaking after the split until you copy lots of sources back and forth between sub-lists), plus also complicating cross-references between entries.  One possible solution to some of this is having transclusion-based "total list" pages, with the caveat that users be warned the page will be long and might not work in their browser.  — SMcCandlish ☏ ¢ 😼  01:37, 22 November 2019 (UTC)
 * That all sounds reasonable to me. But I get the sense that, in practice, the "master list" approach is far more popular. Would you agree? I might have a distorted view because I've spent so much time recently browsing lists of lists. Here's a SQL query I hacked together to find "List of foo" names that redirect to something like "List of foo (A–F)". 27 results, and only 13 are of the desired form (where the redirect title is just the base list name). Granted, that only covers lists that are split alphabetically, but still, it seems pretty low. Colin M (talk) 04:16, 22 November 2019 (UTC)
 * Almost exactly half isn't "pretty low" (if we can trust a sample size of 27), especially since many of these splits and what was done with them long pre-date any advice to do anything specific. Rather, no one has cleaned up the old pages in the interim, and some "monkey see, monkey do" copycatting of the unhelpful old method has probably also occurred intermittently, by people copying one list's style to another without seeing whether it's the recommended style.  — SMcCandlish ☏ ¢ 😼  10:51, 22 November 2019 (UTC)
 * That fraction isn't meaningful. It's not like the query is showing that half of alphabetically split lists use this redirect-to-first-article scheme. I wrote the query specifically to find cases where the "List of foos" title redirects to a "List of foos (A-something)", and it happened to also catch 14 false positives of a form I didn't anticipate in my query (e.g. List of record labels starting with B redirecting to List of record labels: A–H).
 * this query finds 102 "List of..." articles that have been alphabetically split, which would make the fraction of interest more like 10-15% (ignoring the possibility of false negatives in my query). Colin M (talk) 02:00, 23 November 2019 (UTC)
 * and, we need to also remember that Wikipedia, despite its labyrinth of policies, notionally has no rules such that, if it is a really stable policy and not a dead one, I think we can make exceptions for really long articles. Doug Mehus' T · C  02:05, 22 November 2019 (UTC)
 * Yeah, for the one you have in mind: While I don't personally think it is "too long" despite being among our longest lists (show me proof that the page crashes any modern browsers or fails to entirely load for editing in any), and I definitely appreciate the in-page searchability of it, there might end up being a consensus in that talk page discussion to split that list, though surely not into 57 year-based micro-lists. Maybe a decade-based approach would work. Also, List of Star Trek: The Next Generation episodes demonstrates a hybrid approach that became possible with the advent of sectional transcludes.  That main list page transcludes the bare episode lists from each season sub-list, producing a one-page searchable total episode list, then for each season it uses  to branch to the season-specific page which provides much more information that just the season's episode list, including an overall plot summary, reaction/review/impact info, production and cast info, etc. This kind of format should not be discouraged just because material written here about list splitting pre-dates sectional transcludes and thus has created an accidental false dichotomy. That said, this hybrid format is not going to be useful for cases like List of The Nature of Things episodes, where the claim is that just a bare ep. list is too long for a single page, and we have no encyclopedic information to provide at a per-season level anyway, other than a bare episode listing.  But we absolutely should not be doing this; it's just a pointless "landing page" waste of the reader's time. (Aside from the fact that this particular list should be re-merged into one page, anyway; the amount of content is nowhere near enough to have justified a split.)
 * A large list may be split due to size, leaving behind an index page, like Lists of airlines pointing to List of airlines of Africa, List of airlines of the Americas etc. Then a selective list is added to the index, List of government-owned airlines, so it is no longer a pure split list index. More lists could be added like World's largest airlines, List of charter airlines, List of defunct airlines, List of low-cost airlines and so on, completely hiding the origins as a split list index. I don't think we should fuss about that. The real question is whether it is useful. Perhaps this essay should have a section on "Long lists" that compares them to categories, and discusses splitting and transclusion. Aymatth2 (talk) 12:51, 22 November 2019 (UTC)
 * This is a good point. However, I think this conflation is an antipattern that we can and should discourage. If an editor is inclined to add orthogonal X lists to the existing "List of X" split article, they should be directed to either:
 * Add them to the "See also" section, as related articles which are not part of the list proper. Example: List of Xbox One games
 * Make a separate "Lists of X" article, and put them there. There's no reason we can't have both List of airlines (as a split list index, or redirect to List of airlines (A–F)), and Lists of airlines as separate articles, each serving different purposes.
 * Colin M (talk) 02:17, 23 November 2019 (UTC)
 * Let's not get too complicated. The complete list of airlines could be split by region/country, by business model (premium, regional, charter etc), by name, by code, by date founded and so on. And then there could be subsets: largest by revenue / passenger miles / airplanes, oldest, safest, rated best, etc. Editors and readers are not going to understand the difference between splits and subsets. They will reasonably expect that all lists of airlines should be listed in Lists of airlines. Aymatth2 (talk) 12:22, 23 November 2019 (UTC)

Tracking category for split list index articles?
I was thinking it would be useful for development to have a tracking category like Category:Split list indexes (possibly with subcats for alphabetical/chronological splits) for these master/index pages described above. Examples of scenarios in which this would be useful: It would also just be useful to be able to readily browse examples when reasoning about policy for these articles. Any objections to me making such a category (or any suggestions for a better title)? I can't find any guidelines on the creation and use of maintenance categories, so I'm guessing there's pretty wide latitude there. Colin M (talk) 04:10, 23 November 2019 (UTC)
 * If it's decided that these should be separated from other LoLs in the category tree, this would make it easy to make category changes en masse
 * Effecting SMcCandlish's suggestion of replacing non-substantive indexes with redirects directly to the first article in the split
 * Renaming all such articles to use singular ("List of...") titles
 * See above. I think this would be getting way too complicated. Lists of lists is an obscure and oddball category with just a few hundred members. Let's keep it simple. Aymatth2 (talk) 12:22, 23 November 2019 (UTC)

Guidance on wording of introductions?
Introductions are hard to write for list articles, but seemingly doubly so for lists of lists. Here's a semi-arbitrary sample taken from Category:Lists of military lists:


 * Lists of gun cartridges
 * There are many lists of gun cartridges:


 * Lists of Victoria Cross recipients
 * List of Victoria Cross recipients may refer to:


 * Lists of World War II military equipment
 * [no intro]

These are all pretty bad, each in their own unique way. I don't know if this page needs its own complement to WP:SALLEAD (I think SALLEAD applies here for the most part, though list selection criteria are less of a thing), but at the very least I'd be interested in examples anyone stumbles on of good LoL intros which might be used as blueprints to improve the rest. Colin M (talk) 03:49, 23 November 2019 (UTC)
 * I agree that the introductions are often poor. None of these examples says what the things listed are. I have added a note at that "A list-of-lists article should comply with the Stand-alone lists guidelines for content, format and style". Not sure how much of that guideline we should replicate here. Off topic, Lists of Victoria Cross recipients includes several splits (alphabetical, branch or service, conflict and nationality) and then some subsets. Aymatth2 (talk) 13:32, 23 November 2019 (UTC)
 * I made an attempt at improving Lists of gun cartridges. It is still weak. I think at minimum the intro should link to an article about the type of thing listed, and should say how the lists are arranged if there is more than a handful of them. Aymatth2 (talk) 15:55, 24 November 2019 (UTC)

Lists of ports
Lists of ports seems to be a hybrid of a legitimate list of lists of seaports, and a disambiguation of lists of seaports, spaceports, airports, computer ports etc. There is perhaps a common underlying meaning of "point of entry". Does anyone have an opinion on whether and if so how this should be broken up or restructured? Aymatth2 (talk) 14:15, 25 November 2019 (UTC)
 * Not sure about the others, but the computer ports entry at the very least definitely brings the list into DAB territory. I could see two possibilities:
 * DABify, and split parts of the current article into one or more lists of lists (e.g. Lists of seaports)
 * Move the computer ports list into a hatnote link with for. (Though I think it's iffy whether seaports and ports of entry/border crossings really belong under the same semantic umbrella.)
 * Colin M (talk) 17:39, 25 November 2019 (UTC)
 * I have gone with option 2, moving the non-shipping ports to List of ports (disambiguation). This is line with the main article Port and Port (disambiguation). I think all the examples in this essay should be reasonably clean, and this one seems better now. Aymatth2 (talk) 14:08, 28 November 2019 (UTC)

Next steps
Any objections if I remove the Brainstorming tag? Would it be premature to add a link to this essay from WP:LISTOFLISTS? Aymatth2 (talk) 18:59, 5 December 2019 (UTC)
 * Since there were no objections, I have taken off the Brainstorming tag. Editors should obviously still feel free to make improvements, but maybe ask for comment on this talk page first before making changes that could be controversial. Aymatth2 (talk) 18:57, 13 December 2019 (UTC)

Thanks for all the lists!
I just wanted to say that the lists of lists, and of course the List of lists of lists, are some of my favorite Wikipedia pages. Thanks everyone for growing and gardening them! --John_Abbe (talk) 07:53, 14 June 2024 (UTC)