I've been looking pretty diligently to try to find any studies that may point to any information regarding code-switching and its frequency among different types of languages, but am not having a lot of luck so far.
I would be curious to know, for instance, if code-switching tends to happen amongst bilingual groups when the languages are more closely related. In my personal experience, I've heard bilingual English-German speakers code-switch much more often than bilingual English-Korean speakers, and while it could be just my own experience, it could be a real phenomenon either due to social circumstances or linguistic circumstances.
Does anyone know of a study on this subject (even if it's something that might just help as a stepping stone to finding further studies)?