On one of the wikis I'm an admin of, we have had some problems with plagiarism and accusations of plagiarism.
We have had a few users take information from other websites (such as guides) and pasting them onto our wiki without reference. We know this is wrong and have tried to entirely remove the added information or added sources and warn the user.
Many times, though, I feel like they are yelling "plagiarism" over anything that is even similar to their guides. For example, when I was adding information I found from the game and translated myself, they said I was stealing their information and called my a liar when I said I had never even seen their page. If you look at my edits, you can see that I was slowly translating over the day but they would not accept this.
Another editor had taken an image, with credit/sources, that they took from the game. Another user took a section of a scan they had posted, again with credit, and they said it was not allowed.
They have said, in total, that we can not take any information from their pages, reword it, reference it, or allude to it in any way, no matter if it is attributed to them.
My question is, what constitutes plagiarism and what are the rules with this? From my understanding from university, as long as information isn't copy/pasted and is references properly, it is okay to add it.
But what about images? For example, if the image isn't originally their own (as in, it official art, rips/scans from games or guidebooks), then it isn't "theirs" either (though images have always been removed).