Relating to the last post (Geographic Research in America), I found the similar research in Japan version from the web page of The Association of Japanese Geographers (AJG).
AJG conducted a survey of geographic features on 25 colleges and 9 high schools in Japan.
Japanese people who can point the exact place of the U.S are 96%, India is 96.8%, and Brazil is 92.8%. These are well-know countries in Japan. North Korea is 90.3%, France is 87.8% and Vietnam is 73.6%.
In the meantime, people who can point the place of Ukraine are 43.8%, Greece is 67.9% and Iraq is 54.6%.
This survey shows that unfamiliar or faraway countries seem to be difficult to be known the places for Japanese people. Since Japan is surrounded by the ocean and not bordering on the any country, it might be a little hard to perceive the continental and boarding countries.
For me, I still cannot point countries in Europe and Middle East with complete confidence. Furthermore, I honestly have no idea about countries in Africa (Sorry).