What should be rules for making and using tags?

One rule per answer, upvote if you agree, downvote if disagree.

• @mbq I am glad to see this thread. – svadali Sep 19 '10 at 16:47
• @Srinkant I just hope it will gather some attention... – user88 Sep 19 '10 at 16:52
• @mbq I am sure it will gather more attention than the chat threads and in any case I feel that this is a step in the right direction. At least we are taking due diligence by seeking community opinion. – svadali Sep 19 '10 at 16:59
• +1, great idea: thanks mbq and Srikant! – ars Sep 23 '10 at 5:21
• I think that tags that are only attached to a single question are removed automatically after 6 months. Unfortunately, I can't find the meta.SO thread that mentioned this. – csgillespie Oct 2 '10 at 20:41
• @csgillespie And what happens to questions that will be left untagged by this process? On the other hand we can ask on Teachers' Lounge. – user88 Oct 3 '10 at 17:21

Each statistical application/programming language gets its own tag

Like [R], [stata], [ruby], [python], [statistica], ...

• Could these be coloured in a special way to differentiate them from the rest? (for instance, I see that the "featured" tag is red in this discussion) – nico Sep 22 '10 at 7:30

If you don't know what tag to use, use [for-retag]

This will be an invitation for (powerful enough) users to retag the question appropriately. Old ones can be fixed during some retag campaigns coupled with chat discussion.
On the other hand, we can discuss lowering the reputation threshold to make such retags with SE team.

There will be no [statistics] or [statistical-analysis]

In theory it can be useful for pure statistical theory, but on the other hand it would be used by new users to tag almost all questions. On the other hand, [theory] can be used in this case.

(This will sound like a bunch of rules but it's really just one.)

Tags should accurately reflect both the nature of the question and the answers and comments that accompany it (i.e., tags need not describe only the question)

• ... in such a way that each individual tag clearly discriminates the thread from other threads

• ... but so that the collection of tags almost uniquely identifies the particular thread to which it's associated

• ... without being too numerous.

When this is not possible to do using current tags, either a new tag (or tags) need to be generated or--with due care not to upset older threads and their tags--existing tags could be modified.

• Tagging answers is a very nice idea; frequently OP does not have an idea what is his problem called (this is something very different from SOFU), so he/she applies nonsense tags. On the other hand few minutes after we have a good answer like "Google for X". – user88 Sep 19 '10 at 21:12
• Excellent point(s) -- "whuber's three laws of tagging" or that's how I intend to refer to these hereafter. :) – ars Sep 23 '10 at 5:23

Shorter tags are better

For instance [pca] instead of [principal-component-analysis]. Tags have length limit. Abbreviation conflicts can be fixed using synonyms.

• I guess that a bit of effort should be taken to fill in the "tag info" (by those who are allowed to of course) when using abbreviations. In that case if I see pca and I don't have a clue what it means I can go on the "about this tag" link and read it. – nico Sep 22 '10 at 7:27

Individual researchers/authors/etc. should not be tagged.

I could actually go either way on this one, but the recent question on Nassim Taleb got me wondering.

Popular packages/modules should have their own tags

I was the person that added the e1071, so I obviously disagree with the idea proposed by @onestop.

The question being discussed currently has two tags: R & e1071. I would argue:

• Just having the R tag by itself isn't particularly useful for any question.
• For this particular question, other tags don't really fit well, For example, mle or Bayesian doesn't seem right. In the future the only person who will be interested in this question is someone who is using the e1071 package. Why not use it as a tag?
• We can have up to five tags. Most questions only have 2 or 3 tags.
• The R tag is the most popular and is currently used in 15% of posts. It seems like an obvious way to help searching for R is to use package names.
• @onstop suggests that only main packages have there own tags, i.e. ggplot2. However, e1071 is used by a number of bioconductor libraries. Therefore, (I would guess) it is probably used by more people than ggplot2. Admittedly, most people don't know it ;)
• SO overflow use packages tags for searching. For example, an Rcpp tag exists.
• A tag is deleted after six months if it is an orphan.
• Most posts in this site suffer from a shortage of tags, why delete tags?
• The R & c++ example seems strange. Again taking SO as an example, no Rcpp post has a c++ tag. It seems like obfuscation to remove the Rcpp tag.
• +1 Agree; my new private judgement for tags is whether it is reasonable to give someone a this-tag-badge. e1071 for e1071 hackers? not a problem for me. Rcpp for Dirk? So obvious (-; – user88 Oct 27 '10 at 22:15

Site-wide retags (aka massive retags) need community consensus unless they involve one or more of the following;

• Spelling errors
• Retags that leverage established renaming rules

A retag of an individual question need not have a corresponding meta thread unless it attracts controversy.

• Could the downvoter explain why this is not a good idea so that perhaps the weakness of the proposal can me ameliorated? – svadali Sep 21 '10 at 14:04
• I didn't downvote this (in fact I upvoted it earlier) .. but maybe add a note to distinguish "housecleaning" massive retags from other kind of retags. By housecleaning, I mean things like spelling fix, well accepted renaming, etc since it would be nice to not have to go to the community for small matters. – ars Sep 23 '10 at 5:29
• @ars makes sense. I will edit the proposal. – svadali Sep 23 '10 at 11:33

Adding new tags by retag should be exceptional

... in general, we should use those rules to cope with arriving tags from user questions, not to proliferate new tags to fulfill some rule and then glue it to existing questions.
Exception: merging, unexpected special issues.

Each method gets its own tag

... but on reasonable generality level, eg. [cross-validation] not [elevenfold-cross-validation-with-random-resampling-for-butter-taste-data].
Reasonably general can be judged in such a way: we wait a month and see if any other question used the tag. Exception: if a [submethod] tags 100% of [method], we delete it.

• Generally, I would agree with this proposal but I would leave issues such as this to grow organically as suggestd by @ars in chat. – svadali Sep 19 '10 at 16:51
• @Srikant Ok, but this rules are not about how to make a fixed structure, rather than how to control the growth of a flexible one. This also applies to term and app/proglang proposal. – user88 Sep 19 '10 at 21:06

Each notable term get its tag

Like [hetroscedasticity], [ordinal], [median], [categorical-data], ...
Some of those tags may be not fully justified, but they build some kind of context for questions.

• Generally, I would agree with this proposal but I would leave issues such as this to grow organically as suggestd by @ars in chat. – svadali Sep 19 '10 at 16:52
• @Srikant Ok, I probably missed that issue -- I'll add it as a next rule proposal. – user88 Sep 19 '10 at 16:54

Tag should be such its tag badge is reasonable

Users active in certain tags will be automatically awarded with tag badges (bronze and silver). We can't do anything with it, so the "senseness" of such badges should be an argument for tag existence.

• So when considering each new tag, we would ask ourselves, "Would it make sense for someone to have a [say, ggplot2] badge?" That's a pretty intriguing idea, and I had to go look at the list of tags to see how it would go. What about tags like "standard-error" and "books"? – Matt Parker Oct 27 '10 at 22:36

No tags for software-specific commands, functions, modules, packages

Maybe allow exceptions for a very few of most popular ones or wide-ranging such as ggplot2, but otherwise (re-)tag questions with the name of the statistical software / application / programming language and a tag for the method rather than a tag for the name of the command/function/package/module implementing the method in that particular statistical software / language.

• This was precipitated by a questioner creating an 'rcpp' tag, which I replaced by 'r' and 'c++' tags, and another one creating a 'e1071' tag, which i initially assumed was an error message from the internals of stackexchange. – onestop Oct 27 '10 at 18:17
• There was also a 'ltm' tag added (then removed) and one query for adding a 'ggplot2' tag. Tagging software (Stata, SPSS, R, etc.) should be sufficient (IMO). I don't see any particular reason to tag R packages, even for 'ggplot2'; at best, people interested in the Grammar of Graphics have some other tags to refer to (data-visualization, etc.) – chl Oct 27 '10 at 19:16
• Can you expand on the logic of this one? If someone comes here looking for answers about Rcpp or ggplot2, wouldn't it be beneficial to have a tag for them to find previous such questions? – Matt Parker Oct 27 '10 at 19:35
• I've responded to @onestop's answer in a separate answer – csgillespie Oct 27 '10 at 21:05

Automatically kill tags that are too narrow where "too narrow = one question".

Unless the narrow tag is supported by a high rep user.

• -1. Reminds me of the "cold start" problem. Tags should be informative and "narrowness" is a secondary consideration at best. See whuber's answer for better considerations. Also, high rep simply not relevant. – ars Sep 23 '10 at 14:30
• I'm pondering the "not relevant comment." Tagging is an activity automatically limited to users with a minimum rep, to be sure. But higher rep implies more experience with the site, more exposure to the constellation of tags, and likely reflects someone with a more refined sense of what is working and what is not. I personally will be inclined to defer to someone with substantially higher reputation for these reasons. – whuber Sep 23 '10 at 14:42
• @whuber: Sorry, I could have been clearer. I'm looking at the proposition in its entirety: "automatically kill ... unless ...". I suppose my primary objection would be to such a rule automatically kicking in. (For example, how does a high rep user even begin to show "support" for a tag before it's killed (automatically)?) – ars Sep 23 '10 at 14:55
• It can be done with wiki; I have updated proposal. – user88 Sep 23 '10 at 15:02
• @mbq: But them we're creating bureaucracy and process for people to support a tag, and none for people who want to kill tags? In other words, why have such a rule be automatic in the first place? – ars Sep 23 '10 at 15:10

Each retag needs a meta discussion

As question-closing thread during good old times.

• Yes, provided the retag is a massive retag across the whole site and hence we need community consensus. Otherwise, no. A retag of an individual question need not have a corresponding meta thread unless it attracts controversy. – svadali Sep 19 '10 at 16:49
• @Srikant So downvote it and post your proposition as an answer. This thread is intended to become a well established codex made of top-voted answers. – user88 Sep 20 '10 at 9:02
• Done........ – svadali Sep 20 '10 at 10:40

Each tag should have its 'caretaker'

... that will know what the tag mean, protect it from blood-wanting moderators, write its wiki, suggest synonyms and make necessary retags.

• I am not sure this is needed. There will be too many tags and too few high-rep users willing to take care of the tags. This adds extra burden on a few users. Perhaps, we can re-visit this if tag edit wars becomes an issue. – svadali Sep 19 '10 at 16:53
• I think the number of (good) tags will rise slower than the number of users, so this should scale pretty nice. – user88 Sep 19 '10 at 20:57
• -1, tags should be informative, they don't require shepherds. – ars Sep 23 '10 at 13:37
• @ars but people make errors. – user88 Sep 23 '10 at 14:59
• I don't think tag caretakers should feel dedicated to any particular tag...and all who understand these issues should take care in addressing them across all tags to the best of their ability. – Nick Stauner Jan 27 '14 at 2:07