elasticity measures “responsiveness” to change in price (measures a movement; price effect)
TRANSCRIPT
Elasticity
Measures “responsiveness” to change in price
(Measures a Movement; Price Effect)
Price Elasticity of Demand
Sensitivity of quantity demanded to price changes
Elastic: Small P-change, large Q-demanded change
Inelastic: Large P-change, small Q-demanded change
Elastic, Inelastic
Elastic – E(d) > 1 Inelastic – E(d) < 1 Perfect Inelastic – completely price
Insensitive – E(d) = 0 Perfect Elastic – Completely Price Sensitive
– E(d) = infinite
Coefficient of Price Elasticity
To determine how elastic a product is, in other words, how demand for that product will be affected by a change in price, use the following equation.
E(d) = ( QD/QD) / ( P/P) Allows us to compare across markets and
other goods
Practice
Starting at Price P1 = 20, Quantity Q1 = 200 Price goes to P2 = 24, Quantity Q2 = 180
P1 = 20 Q1 = 200 P2 = 24 Q2 =180
[(180-200)/200] / [(24-20)/20](20/200) / (4/20) = .1/.2E(d) = .5
Elasticity and Demand Curves
Example: 10% Price Increase
D Inelastic [E(d) < 1] QD decrease less than
P increase D Elastic [E(d) > 1]
QD decreases more than price increase
Elasticity and Demand Curves
0
20
40
60
80
1 2 3 4 5
Quatntity DemanedPr
ice Inelastice
Elastic
P1 = 40 P2 = 44
QD for each curve?
Practice
Determine the Elasticity.
P1 = 2 P2 = 4
Demand
0
2
4
6
1 2 3 4 5
Quantity Demanded
Pric
e
Demand
Practice
Determine the Elasticity. P1 = 100 P2 = 200
Demand
050100150200250
1 2 3 4 5
Quantity Demanded
Pric
e
Demand
Example
Reaction to raise in price of cigarettes by Teenagers and Adults.
Teenagers Adults
Why is there a greater reaction from the teenagers?
Perfectly/Inelastic Demand
Perfectly Inelastic: QD is unresponsive tp P change Draw a demand curve that displays Perfect Inelasticity. Examples
Perfectly Elastic: QD totally responsive to P change Draw a demand curve that displays Perfect Elasticity. P-increase: QD = 0 P-decrease: buyers buy all they want Examples
The Elasticity of a good’s demand tends to increase with:
Number of closes substitutes.
If there are 10 brands of bicycles available and the prices for one of them increase, the quantity of that brand demanded is likely to fall a lot.
Elasticity (Cont.)
The proportion of income spent on the good.
Consider gum and cruise price-change scenarios. The quantity of cruises purchased will probably be more affected by a 50% price increase than the quantity of bubble gum because an extra 2 cents is not a big deal but an extra $500 is more likely to be prohibitive.
Elasticity (Cont.)
Time When time is short, it is more difficult to
change purchasing patterns in response to changes. The more time consumers have to adapt, the more they are able to find substitutes or learn to do without goods whose prices have increased.
Elasticity (Cont.)
The lack of importance of a good The less essential a good is, the more likely
consumers are to forego the good when it becomes more expensive.
Luxuries v. Necessities
Goods with an elastic demand are categorized as luxuries.
Goods with an inelastic demand are categorized as necessities.
Why should a business care about the elasticity of demand?
One reason is that the elasticity determines what happens to revenue when price changes.
Revenue = Price x Quantity When facing a inelastic demand, to bring in more revenue
while selling fewer units, raise the price of the good.