需求作用估计与进口决策——试析中国谷物进口逆向效益反应的原因孙中才１．引言６０年代以来，中国除少数年份谷物净出口外，多数年份谷物净进口。其中，在１９７８～１９９５年改革开放的１８年中，有５年谷物净出口，其余１３年谷物净进口，而１９９５年净进口量达到１... Demand and Demand Estimation and Import Decision - Analysis on the Reasons for the Inverse Benefit Response of China ’s Grain Importation Sun Zhongcai 1. Introduction Since the 1960s, except for the net cereal exports in a few years, China imported net cereals in most years. Among them, during the 18 years of reform and opening up from 1978 to 1995, there were 5 years of net cereal exports and the remaining 13 years of net cereal imports, while the net imports in 1995 reached 1 ...