、需求收入弹性 (二)需求收入弹性的种类 Normal goods goods whose demand increases as consumer income increase. They have a positive income elasticity of demand. Luxury goods will have a higher income elasticity of demand than more basic goods 正常品( ormal good 劣等品( inferior good)（二）需求收入弹性的种类 ▪ Normal goods Goods whose demand increases as consumer income increase. They have a positive income elasticity of demand. Luxury goods will have a higher income elasticity of demand than more basic goods. ▪ 正常品 (normal good) ▪ 劣等品 (inferior good) 一、需求收入弹性