Table 1.

Sampling frame

	Male (384)										Female (366)
	Han (350)					Minority (34)					Han (333)					Minority (33)
Education	1	2	3	4	5	1	2	3	4	5	1	2	3	4	5	1	2	3	4	5
n	9	94	131	57	59	1	9	13	5	6	10	89	124	54	56	1	9	12	5	6

Education: 1: illiterate; 2: primary; 3: junior high school; 4: high school; 5: university, n Number of people, Han Han nationality, Minority Minority nationality