、需求收入弹性 (一)什么是需求收入弹性 (Income elasticity of demand) Income elasticity The responsiveness of demand to a change in consumer income The major determinant of income elasticity of demand is the degree of 'necessityof the goods. 需求收入弹性被用来表示消费者对某种商品需求量 的变动对收入变动的反应程度。（一）什么是需求收入弹性 (Income elasticity of demand) Income elasticity The responsiveness of demand to a change in consumer income. The major determinant of income elasticity of demand is the degree of ‘necessity’ of the goods. 需求收入弹性被用来表示消费者对某种商品需求量 的变动对收入变动的反应程度。 一、需求收入弹性