4. Elasticities Flashcards
Define elasticity
ELASTICITY: a measure of responsiveness
Define elasticity of demand
ELASTICITY OF DEMAND: measure how much the demand of a product changes when there is a change in one of the factors that determine demand
Elasticities of demand
- PED - price
- XED - price of another good
- YED - income
Define PED
PED: a measure which shows how much the quantity demanded changes when there is a change in the price of the product
PED formula
Range of PED (perfectly elastic/inelastic)
0 - infinity (theoretically, real values in between)
If PED = 0, change in price - no effect on quantity demanded -> demand perfectly inelastic
If PED = infinity, slightly change in P - significant change in quantity demanded -> demand perfectly elastic
Inelastic demand
INELASTIC DEMAND: 0
CHnage in price - proportionally smaller change in quantity demanded - total revenue for firm will increase
Revenue boxes: a+b > b+c
Elastic demand
ELASTIC DEMAND: 1
Change in price - proprotionally bigger change in quantity demanded - firm revenue will fall
(to rasie revenue should lower price)
revenue boxes: a+b < b+c
Unit elastic demand
UNIT ELASTIC DEMAND: PED=1
Change in price - proportionate change in quantity demanded - revenue will not change
Change in PED
In one diagram PED can vary at different points - the lower the price - the more inelastic PED - unlike high price (consumers there are less concerned with the price)
Determinants of PED
- Number, closeness of substitutes: the more substitutes - the more elastic (butter)
- Necessity of the product and how widely it is used: food less elastic than luxury holidays (habit-forming - low elasticity - cigarettes, alcohol)
- Time period considered: times change - consumer habits change - less elastic in short term - more leastic in long term
PED and taxation
Consider elasticity when placing taxes - harm market + create unemployment
Define XED
XED: a measure how much the demand for a product changes when there is a change in price of another product
XED formula
Range of XED
XED ranges from positive to negative
XED > 0 goods are substitutes
XED < 0 goods are complements