Notes: 1 mu is 1/15 hectares; age² is the square of household head age; education is education condition of household head; health condition is the health condition of household head; family labor ratio is equal to number of labors over family size, and family labors including all family members who ware able-bodied, not in school and between 16 and 65 years old (Huang et al., 2012); off-farm income ratio is equal to off-farm income over total income; per capita land area is equal to contracted farmland over family size; wheat profit per mu and maize profit per mu are average values of households for each village; profit=price×yield-production cost (including labor cost, machine cost, seed cost, water cost, fertilizer cost, chemical cost and all other fees for material and service purchased for wheat or maize production), without including subsidies, and labor cost includes the cost of hired labor and family labor, machine cost includes the cost of rented machines and machines owned by households; grain subsidies is the answer of household to the question that “Have your family received grain subsidies last year?”; land reallocation is the frequency of farmland that has been reallocated by any kind of reallocation, since the start of Household Contracted Responsibility System; land transfer policy is the answer of household to the question that “Do you know that the Chinese Central Government are encouraging farmland transfer?”