Download Elasticity and Its Applications

Breve introduzione all’economia politica
ai fini del corso di Economia Ecologica
1.  L’equilibrio parziale: la domanda e l’offerta
-
la domanda
l’offerta
varie applicazioni (prezzi min e max)
spostamenti delle curve
elasticità
applicazione: l’introduzione di una imposta unitaria
2. Efficienza
- concetto generale
- perdita di benessere in monopolio
3. Zoom sull’offerta
-
la
le
la
la
massimizzazione del profitto
differenze tra i vari mercati
curva di offerta della singola impresa
curva di offerta aggregata nel breve periodo
23)
Elasticity and Its
Applications
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1.  L’equilibrio parziale: la domanda (D)e l’offerta (S) (d)
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Price elasticity of demand =
Percentage change in quantity demanded
Percentage change in price
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Price elasticity of demand =
Percentage change in quantity demanded
Percentage change in price
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Price elasticity of demand =
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(P2 ! P1 ) / [(P2 + P1 ) / 2]
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(a) Perfectly Inelastic Demand: Elasticity Equals 0
Price
Demand
$5
4
1. An
increase
in price . . .
0
Quantity
100
2. . . . leaves the quantity demanded unchanged.
Copyright©2003 Southwestern/Thomson Learning
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(b) Inelastic Demand: Elasticity Is Less Than 1
Price
$5
4
1. A 22%
increase
in price . . .
Demand
0
90
100
Quantity
2. . . . leads to an 11% decrease in quantity demanded.
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(c) Unit Elastic Demand: Elasticity Equals 1
Price
$5
4
Demand
1. A 22%
increase
in price . . .
0
80
Quantity
100
2. . . . leads to a 22% decrease in quantity demanded.
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(d) Elastic Demand: Elasticity Is Greater Than 1
Price
$5
4
Demand
1. A 22%
increase
in price . . .
0
50
100
Quantity
2. . . . leads to a 67% decrease in quantity demanded.
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(e) Perfectly Elastic Demand: Elasticity Equals Infinity
Price
1. At any price
above $4, quantity
demanded is zero.
$4
Demand
2. At exactly $4,
consumers will
buy any quantity.
0
3. At a price below $4,
quantity demanded is infinite.
Quantity
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Income elasticity of demand =
Percentage change
in income
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(b) Inelastic Supply: Elasticity Is Less Than 1
Price
Supply
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4
1. A 22%
increase
in price . . .
0
100
110
Quantity
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Copyright©2003 Southwestern/Thomson Learning
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(d) Elastic Supply: Elasticity Is Greater Than 1
Price
Supply
$5
4
1. A 22%
increase
in price . . .
100
0
Quantity
200
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(e) Perfectly Elastic Supply: Elasticity Equals Infinity
Price
1. At any price
above $4, quantity
supplied is infinite.
$4
Supply
2. At exactly $4,
producers will
supply any quantity.
0
3. At a price below $4,
quantity supplied is zero.
Quantity
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(a) Perfectly Inelastic Supply: Elasticity Equals 0
Price
Supply
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4
1. An
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in price . . .
0
100
Quantity
2. . . . leaves the quantity supplied unchanged.
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Breve introduzione all’economia politica
ai fini del corso di Economia Ecologica
1.  L’equilibrio parziale: la domanda e l’offerta
-
la domanda
l’offerta
varie applicazioni (prezzi min e max)
spostamenti delle curve
elasticità
applicazione: l’introduzione di una imposta unitaria
2. Efficienza
- concetto generale
- perdita di benessere in monopolio
3. Zoom sull’offerta
-
la
le
la
la
massimizzazione del profitto
differenze tra i vari mercati
curva di offerta della singola impresa
curva di offerta aggregata nel breve periodo
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Price of
Wheat
1. When demand is inelastic,
an increase in supply . . .
2. . . . leads
to a large fall
in price . . .
S1
S2
$3
2
Computing the price elasticity
of demand
110 !100
(100 +110) / 2
ED =
" !0.24
2!3
(3 + 2) / 2
Demand
0
100
110
Quantity of
Wheat
3. . . . and a proportionately smaller
increase in quantity sold. As a result,
revenue falls from $300 to $220.
Demand is inelastic
1.  L’equilibrio parziale: la domanda (D)e l’offerta (S) (c)
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