胡老师

When the income elasticity of domand is less than 1 but greater than zero, the percentage of income spent on the good decreases as income increases.　我认为这个话是错误的，收入的弹性系数大于0小于１的话，是正常的商品，收入上升，需求也是上升的，只是上升的幅度比收入小而已。而大于１的为奢侈品，小于0的为劣等品。我同意你的看法