For normal goods the demand for X varies inversely with the price of X. There are two main reasons for
this.
For any price change there is a substitution effect and an income effect. For example if the price of
Tesco Steak falls, some consumers will switch towards Tesco steak (away from other brands or other
meats) – because it has become relatively cheaper. More utility can be gained from each pound spent.
This switching of demand is called the substitution effect.
If the price of steak falls, consumer can now afford to buy more with their income/budget. We say that
their real income has increased (they can buy a bigger quantity of steak per week or per month).
Providing that the good has a positive income elasticity of demand, the income effect will also cause
the consumer to buy more Tesco steak when the price falls.
In this case the income and substitution effects are both working in the same direction. Demand will
rise when price falls.
The same relationship holds for an inferior good except that the income effect causes consumers to buy
less when the price falls. However the substitution effect is assumed to be greater so demand stil
The Essay on Price Elasticity of Demand of Newspapers
The price elasticity of demand measures the responsiveness of quantity demanded to a change in price. In other words, it measures by how much the quantity demanded will vary if there is a change in price. If a small decrease in the price of the product causes a huge increase in the quantity demanded, then the product is said to be price elastic. When the demand is price elastic, a fall in price ...
expands at a lower price (and contracts at a higher price)
Some goods are said to ignore the normaly law of demand. We are talking here of Giffen Goods and
Veblen Goods. These are very different types of products. Giffen Goods are strongly inferior. Veblen
goods are sometimes known as goods or services of ostentatious consumption. Here demand rises with
price if the market price is taken to be a sign of quality or where consumers are more concerned with the
satifsaction gleaned from other people seeing them consuming expensive products. designer clothes and
the Jim Keefe revision guide to A-Level Economics spring readily to mind as good examples to use.
