Change in demand:  Impact of non-price factors (increase in income)
Channel: Werner Lost
Date: 2012-11-27

Non-price factors are things such as tases and preferences,  income, number of buyers, price of related goods, expected prices, etc. 

An increase in income increases the demand for a good or services and shifts the demand curve to the right. 
A normal good is a good for which an increase in income results in an increase in the demand for the good. These goods have a positive income elasticity of demand. In other words a positive increase in income leads to a positive change in demand.  

An inferior good is  good for which an increase in income results in a fall in the demand for the good (eg. bread and coal) as consumers switch to other more expensive products (from bread to meat). These products will have a negative income elasticity of demand. In other words, a positive increase in income leads to a negative change in demand