Transcript Document
Shifts in Demand
INCREASE IN DEMAND
A change in one of
those “other factors”
may cause an
increase in demand.
This means that
“Ceteris Paribus” no
longer holds.
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$
D’
D
Q
There are 4 things that will
move the demand curve
1. A change in tastes and
Preferences
This
may be influenced by
advertising, values, the
weather, the season or
fashion.
2. Income
If peoples incomes increase, their demand for
Normal goods will increase.
If the goods are inferior then as income rises,
demand for them falls.
Any changes to income tax rates will effect
disposable income (income left after paying tax.
A reduction in income tax rates will increase
disposable income, increasing demand
NORMAL GOODS
Are products that we
demand more of
when our income
rises. Most products
have this “normal”
relationship.
INFERIOR GOODS
Are products which
we buy less of as our
income rises. As our
income increases we
switch our spending
towards higher quality
products.
3. SUBSTITUTES
Substitutes are
products that we can
use instead of each
other. If the price of
one rises, the quantity
demanded falls
causing an increase
in demand for the
other.
Activities
1.
Bradley has an MP3 player that he was
given when he was 9 years old. Now that
he is 14, he sees that many of his friends
have an ipod touch.
Draw
a graph of the likely effect this
realisation will have on Bradleys demand
for an ipod touch.
SUBSTITUTES
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P
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d’
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BUTTER
d
MARGARINE
Price of butter falls. Quantity demand for butter increases. Demand for
margarine falls
4. COMPLEMENTS
Complements are
products that we
usually use together.If
the price of one rises,
quantity demanded
falls causing a
decrease in the
demand for the other.
COMPLEMENTS
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P
d
CARS
Q
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d”
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PETROL
Price of cars falls. Quantity demanded for cars increases. Demand for
petrol increases.