Google AdSense, an advertisement service, documents in "Opening the ads in a new window":
Generally, it is our policy to not allow Google ads to open in a new window. However, in a few markets, including China, we've found that opening ads in a new window better aligns with expected internet behavior and provides a more consistent, intuitive user experience.
Is there any published research about the culture/country difference regarding opening links in new windows/tabs?
Should we really open external links in new windows/tabs by default for users from these "few markets"? Do these users expect all external links to be opened in new windows/tabs or would an icon/notice still be advisable?
I couldn’t find anything mentioned in the questions: