# Can questions be asked on more than one Stack Exchange site?

No one likes duplicate questions, but I'm considering posting a question about information theory. It would be well-suited to both Cross Validated AND Cryptography. I'd be interested in the opinions of both communities. Can a single question be shared across two (or more) Stack Exchange sites? If so, how? If not, why not?

• I actually kinda like duplicate questions...especially when they're altered slightly to suit their respective sites, and acknowledge one another explicitly. Also, I like to point to this answer on MSE (no longer MSO!) when there's a question worth cross-posting. The tactics there worked for me (more or less)! – Nick Stauner Apr 17 '14 at 5:50
• I actually much like duplicate questions... especially when different talented people hang out at different sites. – Tim Apr 20 '14 at 15:12

## 1 Answer

The term you are looking for is "cross-posting". It is a little bit ambiguous, but the general consensus is that it is inappropriate. This topic has been discussed before on meta.CV; see these threads:

Your situation may be different, though. The typical problem is that someone asks an identical statistics question here and on math.SE (which has a [statistics] tag and small set of dedicated followers), or an R / statistics question here and on SO. Your description is too vague for me to know for sure, but I wonder if the statistical and cryptographical aspects are different aspects of the question. If you want a statistical perspective on something, and a cryptographical perspective on it as well, that strikes me as acceptable. You aren't just fishing for a faster answer, or trying to find someone who'll do your homework for you, and the answers wouldn't provide duplicate information across the SE system.

• Thanks for the answer. The specific question I had in mind is somewhat beside the point, I wanted to learn the proper protocol here. Anyway my question was on the use of entropy in information theory to find the information gained though a process. On the face of it it looks like a purely CV question, but the more I read into it the more it seemed the specific uses of information gain are applied to cryptography! Again, thanks for your complete answer! – FraserOfSmeg Apr 17 '14 at 9:25