Tu par ASV vai Ķīnu? Zem bildes ir links - un tur: "Results are based on telephone and face-to-face interviews with approximately 4,100 adults in China and approximately 1,000 adults in the U.S., aged 15 and older, conducted each year from 2007 to 2011. For results based on the total sample of national adults, one can say with 95% confidence that the maximum margin of sampling error ranged from ±2.1 to ±4.1 percentage points. In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls."