How much is a college degree worth in China?

Fascinating symposium on NYT online about the tough labor market for college graduates in China, who make 1500 yuan per month (about $220) compared to 1200 yuan per month (about $176) for migrant workers, an earnings differential of 25 percent.  In contrast, college graduates earn on average about 75 percent more than high school graduates in the US. 

Why is the payoff to higher education so low in China?  The symposium focuses on these factors: (1) a surge in the number of college graduates this decade has not been matched by a surge in white collar jobs; (2) many of the new schools that have opened do not have very high academic standards; (3) access to college is dictated by a standardized test that does not emphasize the skills most demanded by employers; and (4) a job market that continues to be dominated by manufacturing.