Elasticity Flashcards
What is elasticity
The responsiveness to a change
PeD
Percentage change of quantity demanded/percentage change in price
PeS
Percentage change in quantity supplied/ percentage change in price
XeD
Percentage change in quantity demanded of X/ percentage change in price of Y
YeD
Percentage change in quantity demanded/ per a change in income
What happens if PeD is greater than 1 or less than -1
Good is price elastic
Quantity demanded is highly responsive to change in price
What happens if PeD is less than 1 but greater than -1
Good is price inelastic
Quantity demanded is not very responsive to a change in price
What happens if PeD is equal to 1
The good is unit elastic
The percentage change in quantity demanded is equal to the percentage change in price- proportionate
What happens if PeD is equal to 0
The good is perfectly inelastic
A change in price will have no impact on quantity demanded
What happens if PeD is Infinity
The good is perfectly elastic
Any change in price will see quantity demanded fall to 0
Key factors affecting PeD
Substitutability
Time
Necessity/luxury
%income spent on product
What is substitutability
The more close substitutes a product has the more price elastic it’s demand will be
How does time affect PeD
Short run PeD will be price inelastic
What is income elasticity of demand
Measures the responsiveness of demand for products to changes in the levels of disposable income in an economy
YeD
Percentage change in quantity demanded/percentage change in income