This passage is from 'The Economist'. I have to make notes on it, but I don't understand what it means. Please could you help?
"Many imports from China have moved up-market from easy-to-produce products, such as footwear, to more sophisticated goods, such as computers and electronics. As a result, to use economists' jargon, the “factor content” of American imports—in effect, the amount of skilled labour they contain—has not shifted downwards. Mr Katz says factor-based models suggest trade with poor countries explains only 5% of rising income inequality."