中文摘要：
  基于家庭经济学和时间配置理论可以证明，劳动剩余条件下的劳动供给并不是无限的。受制于家庭分工的约束，供给曲线呈特殊的阶梯形态：随着劳动供给的增加，农业劳动力的保留工资不断提高，且幅度不断扩大。劳动供给对工资的反应是非连续的：只有当工资上升到新的保留工资水平时，劳动供给才会增加；否则，工资上涨并不能带来供给增长。与这种特殊的供给形态相对应，工资上涨的主要动力从农业收入转向工业劳动需求。内蒙古、甘肃两省1500个农户的调查数据证明了这一判断。当劳动需求扩张时，由于工资的微调不能带动供给的微调，劳动力市场将长期难以出清。这提醒我们，当前农民工工资上涨与用工短缺并存现象很可能源于劳动剩余条件下的供给不足，并不必然意味着剩余劳动力枯竭，不能作为刘易斯拐点到来的证据。
英文摘要：
  On the basis of family economics and the theory of time allocation, it can be proved that labor supply under labor surplus conditions is not limitless. Subject to the constraint of intrahousehold labor division, the supply curve takes on a special staircase form: with the increase in labor supply, the reservation wage of rural labor rises constantly by an increasing margin. The response of labor supply to wage is not continuous: labor supply will increase only when the wage rises to the new level of reservation wage; otherwise wage increases will not lead to the increase in labor supply. Corresponding to this special supply condition, the demand for industrial labor instead of agricultural income becomes the major driving force for wage increases. Survey data on 1,500 rural households in Gansu and Inner Mongolia bear out the above proposition. When labor demand expands while the slight raise of wage cannot bring corresponding increase in labor supply, labormarket clearing will not be realized for a long period of time. This reminds us that the coexistence of wage increases and supply shortage of rural labor may very likely derive from insufficient labor supply under labor surplus conditions. It does not necessarily imply the exhaustion of labor surplus and cannot prove the arrival of the Lewisian turning point.