That is correct, for the Latin Church. The Eastern Catholic Churches fall into Eparchies. The Eparchy functions in much the same way as a RC diocese, except that it falls under a Patriarch.
Have there been any studies on how the married clergy works in the Eastern Rite Churches?
There have been those on this thread who say that we shouldn't use the term Roman Catholic, saying that it is a term of derision. I was merely pointing out that this is poppycock, just like I repeatedly have pointed out that the term "Uniate" is a label the Latins came up with, not the Orthodox. I think that people are just too sensitive about all of this stuff, and on un-PC FR of all places!