Some — perhaps many — academics seem to be very careful in keeping unpublished work secret. It is not difficult to find anecdotes where academic ideas are stolen, such as in this post by @Markus. Others, such as @NateEldredge in this post write that It seems to be pretty common for people starting out in academia to overestimate the risks of people stealing their work. Personally, I'm rather at the other end of the spectrum, and I don't feel afraid that my ideas would be stolen. Perhaps I'm naïve.
Is there any research on the question: how common is academic theft, really? Such as surveys of people having experienced (or committed!) such theft according to an appropriate definition, possibly compared to peoples' perception as to the risks. It would be interesting to see if there are some facts to refer to. Perhaps it is field dependent?
(By academic theft, I am not talking about plagiarism, but rather about stealing research ideas before anything is published)