I wonder which of Chinese and Japanese Korean share more vocabulary with. I investigated it but it seems that the estimated percentage of shared vocabulary varies so much. For example according to the Wikipedia Korean language page:
The exact proportion of Sino-Korean vocabulary is a matter of debate. Sohn (2001) stated 50–60%.[48] Later, the same author (2006, p. 5) gives an even higher estimate of 65%.[43] Jeong Jae-do, one of the compilers of the dictionary Urimal Keun Sajeon, asserts that the proportion is not so high. He points out that Korean dictionaries compiled during the colonial period include many unused Sino-Korean words. In his estimation, the proportion of Sino-Korean vocabulary in the Korean language might be as low as 30%.[49]
But now I wonder then in which of the two languages the vocabulary is more common in Korean. Is there any such study, or at least is there general agreement among Korean speakers who speak both Chinese and Japanese?