# LDA (latent dirichlet allocation) tag issue

Colleagues and moderators, please think over what to do with a tag for Latent Dirichlet Allocation. We've got and currently. One (which? or maybe a new better one?) should be set recommended and the other set synonymic.

Note that lda could be confused with (linear) discriminant analysis for which we have a separate tag .

• We need better tools to rename tags on Stack Exchange. – Franck Dernoncourt Feb 28 '17 at 21:15
• While not directly about tags, Is it reasonable to put “try to avoid acronyms” in the help on asking questions? (posted in 2013) specifically mentions the problem with calling Latent Dirichlet Analysis "LDA" when Linear Discriminant Analysis (which is much older) has the same initials. Three Letter Acronyms are seen as a particular bugbear in the thread there (with particular mention in the answer). – Glen_b Feb 28 '17 at 22:44
• whuber's (lone) answer there (16 votes, 0 down) has the conclusion "We should insist that all acronyms be written out (the first time) in all cases." (I try but don't always succeed).... I think the principle would extend to new tags (as a general principle, to avoid acronyms in their names where feasible, with a few exceptions, like anova). This advice was subsequently placed in the Style section of our site's How to ask a good question meta post – Glen_b Feb 28 '17 at 22:54

The tag was created relatively recently (several months ago) by @FranckDernoncourt for Latent Dirichlet Allocation. A couple of days ago I realized that people are using this tag to refer to both, Latent Dirichlet Allocation and Linear Discriminant Analysis, which is very confusing.

So I asked @Franck to re-consider and to remove this tag, re-tagging all existing (around 10) questions into either or a [latent-dirichlet]. Franck agreed and suggested [latent-dirichlet-alloc] as a name. Then he did the retagging.

See comments to Course for Latent Dirichlet Allocation for this conversation between him and me.

• Amoeba, thank you for informing and the discussion with @FranckDernocourt. Will Frank transfer the tag description from lda to latent-dirichlet-alloc and warn in lda not to use it? And submit it to become a junior synonym? – ttnphns Feb 28 '17 at 20:33
• The tag description is already transferred. Regarding lda tag, it currently has 0 threads and so will disappear within 24 hours... Hopefully forever :) – amoeba Feb 28 '17 at 20:39
• Is there a way to prevent someone in the future from using lda tag? – Franck Dernoncourt Feb 28 '17 at 21:16
• @FranckDernoncourt In principle, StackExchange allows to "blacklist" a tag. In practice, this is complicated and is never done on CrossValidated (I think to blacklist a tag, one of the mods has to contact SE admins and they will do it). – amoeba Feb 28 '17 at 21:18
• I'd prefer not to delete it - it will be re-created - nor even to try blacklist it. Better to simply put one of the standard "don't use this tag" notes, directing people to use relevant tags for the alternatives. – Glen_b Feb 28 '17 at 23:01
• @Glen_b AFAIK it's not possible to keep a tag with 0 threads so I am not sure what exactly you are proposing. – amoeba Feb 28 '17 at 23:05
• Oh, ... damn. Maybe you're right there. So all our "don't use this tag" messages just die? One possibility (as much as I hate the notion) is to lock one post with the tag. – Glen_b Feb 28 '17 at 23:07
• @Glen_b Yeah, I strongly dislike this option too. Another possible approach would be to have [lda-linear-discriminant] and [lda-latent-dirichlet] tags, with the former one mapped to [discriminant-analysis] and the latter one to [latent-dirichlet-alloc]. This way anybody starting to type "lda" in a tag field will get both options suggested. – amoeba Feb 28 '17 at 23:09
• That's a much more enticing possibility; certainly worth some discussion. – Glen_b Feb 28 '17 at 23:10
• @amoeba Great idea. I wish on Stack Exchange one could mark a tag as "abbreviable", i.e. if [latent-dirichlet-alloc] is marked as abbreviable, the typing lda would bring it up in the suggestions. – Franck Dernoncourt Mar 1 '17 at 2:23
• @amoeba, do by "mapped to" you mean automatic substitute? If yes - then it its is acceptable. For we don't need any [lda-linear-discriminant] to be usable, I think. – ttnphns Mar 1 '17 at 6:57
• I would perhaps support those who think we ought to keep "bad" tags, but with description "Not recommended, use... instead". The colour of such tags or of their description "cards" or of their font should be special, say, magenta. – ttnphns Mar 1 '17 at 7:04
• @ttnphns Yes, I meant an automatic substitute, as a tag synonym. Regarding "bad deprecated tags": it could work well, but StackExchange does not support this functionality so it's not something we can use at the moment. – amoeba Mar 1 '17 at 8:39