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Questions tagged [exact-duplicates]

This tag is referring to the process of identifying and closing questions that are exact duplicates of another question.

79
votes
10answers
7k views

Coping with *abstract* duplicate questions.

Any longtime reader cannot help but notice that we get many abstract duplicate questions, e.g. this recent question on partial fraction computation, which is not essentially different from many other ...
38
votes
3answers
968 views

Large number of posts in the spirit of “How do I become good at Mathematics?”

There have been a steady number of questions being asked in the spirit of: Hi, I'm yada yada. Here's a short version of my life story and why I can't math. I currently only understand such and ...
32
votes
0answers
338 views

Improving the search system

When recognizing some questions as duplicates, sometimes it is difficult to find the original question one remembers. For instance, I recently saw a question asking to prove that $$\forall x\in(-1,1),\...
30
votes
1answer
640 views

Is it acceptable to post a “better” version of an existing question?

Situation: Lets say there was an interesting question, but: It was poorly written (e.g. language, formatting, missing assumptions). It was posted many day ago but got only a few views. It received ...
28
votes
4answers
470 views

Voting to close as duplicate without taking the time to check if they are

This question has 4 votes to close as being an exact duplicate of this one. Within an hour of the question being asked, someone voted to close it as an exact duplicate AND Davide Giraudo pointed out, ...
27
votes
5answers
757 views

What if the duplicate has a better answer than the original?

I have recently asked a question (The original did not turn up in my search): Show that there are infinitely many powers of two starting with the digit 7 which was marked as a duplicate of: Starting ...
27
votes
1answer
472 views

Whither the duplicate?

Ironically, I'll bet this question is a duplicate of other questions regarding duplicates, but I see little harm in sparking some new conversation here, even if we tread over old ground that many ...
27
votes
1answer
2k views

Same person has asked the same question 6 (!) times - what can be done?

I have flagged 4 exact duplicates yesterday https://math.stackexchange.com/users/flag-summary/86800 leaving only one version Integers and integer functions And today a yet another exact duplicate ...
26
votes
1answer
315 views

Is it ok to edit questions that are closed as duplicates?

I think that duplicates can be useful for various reasons. In particular, they might help to find a question if a user searches for different keywords. Similarly, they might appear in autogenerated ...
25
votes
1answer
472 views

Allow closing as duplicate for new questions

One of the changes to the closure system in the recent revamp was that to close something as a duplicate, the suggested duplicate needs to have an upvoted answer. I suppose that's a good thing when ...
25
votes
2answers
422 views

Should we close questions asking for hints as duplicates?

This question was inspired by this question Relationship between $\operatorname{ord}(ab), \operatorname{ord}(a)$, and $\operatorname{ord}(b)$, which I first came across while reviewing close votes. ...
24
votes
1answer
640 views

Why do obvious duplicate questions on MSE get upvoted, answered, and their answers upvoted?

The title is the question: why do obvious duplicate questions on MSE get upvoted, answered, and their answers upvoted? And what can be done to prevent this? Here is an example: https://math....
23
votes
2answers
344 views

A hierarchy of duplicates - which questions generalise other questions?

I think the site would benefit from a hierarchical structure to the duplicate question functionality, indicating which questions generalise others. I was contemplating duplicate questions last night ...
23
votes
0answers
1k views

Help me find an original for questions like “Why $(-1)^{ab} \ne [(-1)^a]^b$ when $a, b, \in \Bbb R$?”

There are many questions that boil down to "why is it not true that $(-1)^{ab} = [(-1)^a]^b$ (or $z^{ab} = (z^a)^b$) for $z \in \Bbb C$ and $a, b \in \Bbb R$ (or $\Bbb C$)?" and, respectively, "...
22
votes
1answer
338 views

How to avoid duplications?

During the last two and a half years since I became a member of the SE community, it has happened so many times that my questions have been marked as duplicate, especially during the first few months ...
21
votes
1answer
851 views

Question having excellent answer marked as dupe of a newer question

A high rep user who posted an answer to this question asked in 2014 marked my question asked in 2012 as duplicate. As such there is nothing wrong with flagging older questions as dupes of newer ones ...
21
votes
0answers
354 views

questions asked over 100 times

I just saw another question with the limit of $(1 + 1/n)^n.$ A few months ago, somebody asked some other multiple repeat question, I wrote to check any of the last 137 times it had been asked. he ...
20
votes
1answer
280 views

“marked as duplicate” by community?

A few minutes ago I flagged this question as a duplicate of an earlier one; when I came back to it, it showed as having been "marked as duplicate by Steven Stadnicki, Community". I've never seen the ...
20
votes
3answers
698 views

Should duplicate questions be deleted?

Lately, I came across several suggestions for deletion of questions simply because they are duplicates. In my opininion: If the question is somehow a bad question, then it ought to be deleted, and so ...
20
votes
1answer
302 views

How can I make sure the problem I want to ask has not been presented before?

e.g. I have a question on proving an inequality statement. If I google it Google will not recognize it and if I use Math StackExchange'search engine, it will not respond. Thank you for your help.
20
votes
2answers
607 views

How do you search for duplicates?

Sometimes I am really surprised how fast are the duplicates of new question found, given that we have vast amount of questions here. I hope posting this question here can be useful and can lead to ...
18
votes
5answers
976 views

How close a match we need to close a recurring question as a duplicate?

An hour ago I closed a question as a duplicate of an, in my opinion appropriate, generic question. Two gold badge holders have since expressed disagreement with my decision, and the question has since ...
18
votes
1answer
1k views

I voted mistakenly to close as duplicate. When I realised my mistake, my comment explaining why was deleted.

I refer to this question: Comparing logarithms with different bases. Over-hastily, I flagged it as a possible duplicate of How to compare logarithms $\log_4 5$ and $\log_5 6$?. I also thought it was ...
18
votes
1answer
307 views

Duplicate of a deleted question

I just came across this question, and it made me wonder what the policy is for deleting questions which have duplicates pointing to them. I don't have any particular stake in this specific question, ...
18
votes
1answer
417 views

Should we have a canonical question on transitive / symmetric / reflexive relations?

It seems that we fairly regularly get elementary questions of the form: "Does a relation that is [A] and [B] have to be [C]?" where [A], [B] and [C] are some permutation of "transitive", "...
17
votes
2answers
332 views

Why are there requirements for duplicated questions?

Today I found a questions to be a duplicate, and I even remembered that I gave an answer to the non-duplicate. As I tried to close the duplicate as a duplicate, it told me I can't choose the question ...
17
votes
1answer
328 views

Meta-Meta question: Duplicate for previous question without actual real answer

So I was perusing the meta site, and I came across this closed link: https://math.meta.stackexchange.com/questions/20285/why-do-we-have-a-tag-called-stochastic-analysis The reason it was closed was ...
16
votes
2answers
616 views

This question is an exact duplicate of: Page Not Found

I stumbled upon this question which was marked as a duplicate, and rightly so as the OP had realised himself in their comment. Checking out the question that it's an exact duplicate of leads to this. ...
16
votes
2answers
266 views

Duplicate Question Where Neither have *Complete* Answers

I just voted to close this question as a duplicate of this other one. However, I am unsure if this was exactly the right action to take, given that, though the latter question has an upvoted answer, ...
15
votes
1answer
407 views

What happens to otherwise good answers when their question is closed?

I answered this question the other day. It was one of those cases when I just happened to see it right as it was posted and it was a fun question that I knew something about. So I gave an answer (...
15
votes
1answer
220 views

What's the difference between duplicate flag and close duplicate flag?

What's the difference between duplicate flag and close duplicate flag? When I want to flag something as duplicated there are two ways: Flagging as a duplicate: Flagging as should be closed → ...
14
votes
2answers
380 views

Proof-verification and duplicates.

When someone posts a question, which asks for verification of their proof of something, the mathematical content of that question will often be a duplicate of another question. Now, in order to help ...
14
votes
5answers
239 views

What to do with a newer post and a related, older, less thorough post?

Let me give a specific example. Today, I answered this post, and my answer seemed familiar. Looking through my old answers, I found that I'd answered this post a while back. The older post is a less ...
14
votes
6answers
1k views

The duplicate thread

This thread is intended to help with closure of duplicates. The main use case are situations where a first attempt at duplicate closure was not successful.1 The creation of this thread was decided ...
14
votes
1answer
428 views

Answering my own new and more detailed question rather than an existing one

Recently I have posted this question: Functions that preserve asymptotic equivalence. I searched MSE and MO sites for related questions before asking, but didn't succeed, my bad. After few days, I ...
14
votes
0answers
242 views

Should a closed question be reopened if it gets a duplicate?

This question How do you prove that $n^2-1$ is composite when $n>2$? was closed as a duplicate. That was the right outcome, as opposed to, you know, "off-topic." But the question it's a duplicate ...
14
votes
0answers
98 views

Request: When closing a question as duplicate, to show all the linked questions

When people post "This question is a duplicate of XXX", would it be possible for the selections shown when we decide to close a question as duplicate, to also show XXX? This could be easily done by ...
13
votes
2answers
390 views

What to do with two old questions that are clear duplicates but not marked so? [duplicate]

Recently I stumbled on the following questions: 1. Proof that a trigonometric function of a rational angle must be non-transcendental 2. Is a trigonometric function applied to a rational multiple of ...
13
votes
4answers
687 views

downvoting because of duplication?

This question has five downvotes, and was closed as a duplicate of a question with 25 up-votes. Should one down-vote a question merely because of duplication? There's no mention of anything wrong ...
13
votes
1answer
181 views

Almost-duplicates of closed PSQs

In this (now deleted) question a user asked about a homework problem (I assume), asking whether a particular approach to it would be valid. Almost immediately, someone voted to close as a duplicate ...
12
votes
1answer
381 views

Is it okay to delete unanswered, marked as duplicates questions?

Just what the title says: I've had many questions marked as duplicates when I first started using this site, and I was wondering if it's okay for me to delete them.
12
votes
1answer
474 views

How aggressively should we tag a question as duplicate?

Some questions seem standard and very likely to have already been asked. For example, a question on Prove Binet's Formula would almost certainly have been asked, even without referring to the links by ...
12
votes
1answer
149 views

Strange link text in a possible duplicate

I've just flagged the question Indefinite integration $\int\frac{(2x^2)}{2xcos(2x)+(x^2-1)(sin(2x))}$ as a possible duplicate of another question posted by the same user. In the link text, a strange ...
12
votes
0answers
166 views

Marking questions as the originals for duplicates

When a question is closed as a duplicate, the ideal result is presumably that the questioner, potential answerers and future visitors will head off to the linked question and that any new answers will ...
12
votes
0answers
334 views

Questions that show no effort to find existing similar questions a.k.a. abstract duplicates

EDIT: After amWhy brought the term "abstract duplicates" to my attention in the comments below, I thought some tidying-up was in order. The original body of the question is mostly intact below; I have ...
11
votes
3answers
341 views

Handling users asking lots of similar questions with little work

I realize that one of the major goals of this site is to help others learn and understand mathematics, and in fact it is one of my favorite parts of math.SE. As such, I don't mind a bit when I see a ...
11
votes
4answers
499 views

Should this question be closed as duplicate?

Here we have an interesting situation: the question Is an algebraic integer all of whose conjugates have absolute value 1 a root of unity? was asked. While there doesn't seem to be an exact ...
11
votes
3answers
336 views

What action to take on identical questions from the same user?

It sometimes happens that the same user posts exactly the same question twice in a row. Examples: 1 2. user asked twice for the probability of choosing 90% of the colors from a collection of $10^{...
11
votes
3answers
379 views

Should we merge the questions on “self-studying abstract algebra”?

There are currently (as far as I know) three community wiki questions with largely the same premise: book recommendations for self-studying abstract algebra. They are Good abstract algebra books for ...