Chapter 4 Demand

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Transcript Chapter 4 Demand

Economics Chapter 4
Demand
Demand
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Demand is the desire, ability
and willingness of a consumer
to buy a product. A WANT
Microeconomics is the study of
the behavior of one consumer or
one business
Macroeconomics is the study of
the economy of the whole
country.
Demand Schedule
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A demand schedule is a
listing that shows the
various quantities
(amounts) demanded
wants) of a product at all
prices you might see in the
market.
Demand schedule for
Snuggies
Price
$$
Qty.
Demanded
$50
$20
$15
$10
$5
0
5
10
27
47
(how many)
(wanted)
Demand Curve
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A demand curve is a
graph showing the
quantity demanded at
each and every price
that you might see in
a market
Snapshot of RIGHT
NOW!
This demand curve goes
DOWN!
Movement on red line on demand curve means there has been
a change in PRICE ONLY. There is ONE curve (line)
Demand Curve
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If $50, quantity demanded =__
If $30, quantity demanded =___
If $5, quantity demanded= ___
Law of Demand
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The Law of Demand states that the
quantity demanded of a good or
service varies inversely with its price.
quantity
price demanded
quantity
price demanded
Cost and demand are
inversely proportional.
If price goes up, demand goes ______________.
If price goes down, demand goes _____________.
Market Demand Curve
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A market demand curve shows
the quantity demanded by
everyone who is interested in
purchasing the product.
Example: buying a new laptop
Demand curve for Tiger Baseball Tickets…
If the tickets cost $25, then ________ people want it.
At $25, ___ people will demand (WANT) that quantity.
If the tickets costs $15, then ________ people want it.
At $15, ___ people will demand (WANT) that quantity.
If the tickets costs $30, then ________ people want it.
At $30, ___ people will demand (WANT) that quantity.
Marginal Utility
Marginal utility is the extra
enjoyment that a person gets
from getting one more!
YES! One more sucker!!!
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Extra
lollipops bring
Erick extra
utility!
Diminishing Marginal Utility
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The principle of diminishing
marginal utility means that the
enjoyment we get from more
decreases.
NOT ANOTHER HOT DOG!!!
Think of eating contests or
block days at KHS!
Section 2
Factors Affecting Demand
When there is a change in a people’s
willingness and ability to buy, it is because
of 2 reasons:
1. Change in QUANTITY DEMANDED
OR
2. CHANGE IN DEMAND
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Change in Quantity Demanded
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A change in quantity demanded is a
movement ALONG the demand curve
that shows ….
a change in the quantity of the product
purchased WHY?
change in PRICE.
Examples:
1. Income effect
2. Substitution
Income: $100 a week
Want gas for car
If gas price
the person buys
(more/less) gas?
If gas price
the person buys
(more/less) gas?
1. Income Effect
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NO INCREASE IN YOUR INCOME ($ earned)…..
If price
then a person feels they can
buy more
If price
then a person feels they cannot
buy as much
If he has more money from winning the lottery, what will the effect be on his spending?
2. Substitution Effect
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CD
The substitution effect is the change in quantity demanded
because of a change in the price of an item.
Example – Substituting a concert ticket for a CD
Will a person buy more CDs or concert tickets?
$12.99
Concert Ticket $34.75
Mississippi mud pie $3
Severn sludge souffle $5
Change in Demand- a SHIFT in Demand
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A change in demand happens
because people are now willing to
buy different amounts of the product
at the same prices.
A CHANGE IN DEMAND WILL
RESULT IN A NEW DEMAND
CURVE. (oh shift!)
There are 2 lines.
Changes in Demand
Original:
price $10,……….Quantity demanded = _____
New Demand
price $10………..Quantity demanded = ______
2.
Consumer tastes
- preferences
1.
Consumer income –
$$$ earned
4.
Complements –
buns for hotdogs
PRICE????
NO NO NO
3. Substitutes–
Pepsi for Coke
What
Changes
Demand?
6. Change in
expectations
5. Change in the
number of customers
Consumer Income
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Changes in consumer income
can cause a change in demand.
Example – you get a raise or
you lose your job
I can buy (more/less)
I can by (more/less)
Consumer Tastes
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Consumers
do not always
want the
same thing.
Example –
change in
fashion, style,
the
development
of new
products
More on Changing Tastes…
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Changing tastes
shift demand
curves (and can
actually be quite
amusing after a
few years!).
Substitutes
$2.75
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$2.00
A change in
the price of
related
products can
cause a
change in
demand.
Substitutes
can be used
in place of
other
products.
Complements
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Related goods are known as
complements because the use
of one increases the use of the
other.
With cereal, you must buy
______________.
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Example – peanut butter and
jelly, hotdogs and hotdog buns
With a hot dog, you must buy
_________ and ____________.
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Elasticity is the what
happens when a
dependent variable
such as quantity
responds to a change in
an independent
variable such as price.
IF
Independent variable $$$$
Elasticity
Pajama bottoms
THEN
If there is a change in
price $$$……
Then the
quantity
demanded
how much
want)changes
Independent variable: $
Dependent variable: what happens?
Dependent variable: qty.
Demand Elasticity
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Demand Elasticity is how much a change
in price causes a change in the quantity
demand
ELASTIC
High pricelow price
Demand change- (quantity want)
big change
small change
little change
INELASTIC
High pricelow price
Demand change- (quantity want)
big change
small change
little change
Elastic
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“Elastic” is when a
change in price causes
a larger change in
quantity demanded.
Example:
Beans in summer $2.00
People buy (more/less)
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Beans in winter $4.00
People buy (more/less)
Inelastic Demand
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Inelastic means that a change in price
causes a smaller change in the quantity
demanded.
People need medicine.
Will continue buy if price is low.
Will continue to buy if price is high.
Unit Elastic Demand
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Unit elastic means that a given change in
price causes a proportional (equal) change
in the quantity demanded. (45˚ angle)
Price increases by $2
Quantity increases by 1
What determines demand elasticity?
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Can the purchase be delayed?
(can I buy it later?)
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Are adequate substitutes available?
(Snickers candy instead of Milky Way?)
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Does the purchase use a large portion of
income?
( I have been saving for a new phone for a long time. Do I want
to use all of my savings for the phone and have nothing left?)