Title: The Classical Long-Run Model
1The Classical Long-Run Model
- Economists sometimes disagree with each other
- Actually much more agreement exists among
economists than there appears to be - Once distinction between long-run and short-run
becomes clear - Many apparent disagreements among macroeconomists
dissolve - If no time horizon is specified, however, an
economist is likely to focus on horizon he or she
feels is most important - Something about which economists sometimes do
disagree
2The Classical Long-Run Model
- Ideally, we would like our economy to do well in
both long-run and short-run - Unfortunately, there is often a trade-off between
these two goals - Doing better in short-run can require some
sacrifice of long-run goals, and vice versa - Policies that can help us smooth out economic
fluctuations may prove harmful to growth in the
long-run - While policies that promise a high rate of growth
might require us to put up with more severe
fluctuations in short-run
3Macroeconomic Models Classical Verses Keynesian
- Classical model, developed by economists in 19th
and early 20th centuries, was an attempt to
explain a key observation about economy - Over periods of several years or longer, economy
performs rather well - If we think in terms of decades rather than years
or quarters, business cycle fades in significance
- In the classical view, this behavior is no
accident - Powerful forces are at work that drive economy
towards full employment - An important group of macroeconomists continues
to believe that classical model is useful even in
shorter run - In 1936, in midst of Great Depression, British
economist John Maynard Keynes offered an
explanation for economys poor performance - Argued that, while classical model might explain
economys operation in long-run, long-run could
be a very long time in arriving
4Macroeconomic Models Classical Verses Keynesian
- Keynesian ideas became increasingly popular in
universities and government agencies during 1940s
and 1950s - By mid-1960s, entire profession had been won over
- Macroeconomics was Keynesian economics
- Classical model was removed from virtually all
introductory economics textbooks - Classical model is still important
- In recent decades there has been an active
counterrevolution against Keyness approach to
understanding the macroeconomy - Useful in understanding economy over long-run
- While Keyness ideas and their further
development help us understand economic
fluctuationsmovements in output around its
long-run trend - Classical model has proven more useful in
explaining the long-run trend itself
5Assumptions of the Classical Model
- All models begin with assumptions about the world
- Classical model is no exception
- Many of its assumptions are simplifying
- Make model more manageable, enabling us to see
the broad outlines of economic behavior without
getting lost in details - One assumption in classical view that goes beyond
mere simplification-critical assumption - Markets clear
- Price in every market will adjust until quantity
supplied and quantity demanded are equal
6Assumptions of the Classical Model
- Market-clearing assumption provides hint about
why classical model does a better job over longer
time periods (several years or more) than shorter
ones - Well use classical model to answer a variety of
important questions about economy in long-run,
such as - How is total employment determined?
- How much output will we produce?
- What role does total spending play in the
economy? - What happens when things change?
7How Much Output Will We Produce?
- How can we disentangle web of economic
interactions we see around us? - Decide which market or markets best suit the
problem being analyzed, and - Identify buyers and sellers
- Identify type of environment in which they trade
- But which market should we start with?
- Logical start is market for resources
- Labor, land and natural resources, capital and
entrepreneurship - Well concentrate our attention on labor
- Our question is
- How many workers will be employed in the economy?
8Figure 1 The Labor Market
LS
B
A
E
H
J
10
Excess Demand for Labor
LD
100 million Full Employment
9The Labor Market
- Labor supply curve slopes upward
- Becauseas wage rate increasesmore and more
individuals are better off working than not
working - Thus, a rise in wage rate increases number of
people who want to workto supply their labor - As wage rate increases each firm will find
thatto maximize profitit should employ fewer
workers than before - When all firms behave this way together a rise in
wage rate will decrease quantity of labor
demanded - This is why economys labor demand curve slopes
downward - In classical view, economy achieves full
employment on its own
10Determining the Economys Output
- Most effective way to master a macroeconomic
model is divide and conquer - Start with part of model, understand it well, and
then add in other parts - Accordingly, our classical analysis of economy is
divided into two separate questions - What would be the long-run equilibrium of the
economy if there were a constant state of
technology - And if quantities of all resources besides labor
were fixed? - What happens to this long-run equilibrium when
technology and quantities of other resources
change?
11The Production Function
- Relationship between total employment and total
production in the economy - Given by economys aggregate production function
- Shows total output economy can produce with
different quantities of labor - Given constant amounts of other resources and
current state of technology - In classical, long-run view economy reaches its
potential output automatically - An important conclusion of classical model and an
important characteristic of the economy in
long-run - Output tends toward its potential,
full-employment level on its own, with no need
for government to steer the economy toward it
12Figure 2 Output Determination in the Classical
Model
LS
15
LD
100 million
Aggregate Production Function
7 Trillion Full Employment Output
100 million
13The Role of Spending
- What if business firms are unable to sell all
output produced by a fully employed labor force? - Economy would not be able to sustain full
employment for very long since business firms
will not continue to employ workers who produce
output that is not being sold - If we are asserting that potential output is an
equilibrium for the economy - Had better be sure that total spending on output
is equal to total production during the year - But can we be sure of this?
- In classical view answer is yes
14Total Spending in a Very Simple Economy
- Imagine a world with just two types of economic
units - Households and business firms
- Circular Flow
- A diagram that shows how goods, resources, and
dollar payments flow between households and firms - In a simple economy with just households and
firms in which households spend all of their
income without saving it or paying tax - Total spending must be equal to total output
- Known as Says Law
15Figure 3 The Circular Flow
Goods and Services Demanded
Resources Supplied
Total Consumption Spending
Total Income
Total Revenue of Firms
Total Factor Payments
Goods and Services Supplied
Resources Demanded
16Total Spending in a Very Simple Economy
- Says Law named after classical economist Jean
Baptiste Say (1767-1832), who popularized the
idea - Each time a god or service is produced, an equal
amount of income is created, For example, - each time a shirt manufacturer produces a
25 shirt, it creates 25 in factor payments to
households. - In Says own words
- A product is no sooner created than it, from
that instant, affords a market for other products
to the full extent of its own valueThus, the
mere circumstance of the creation of one product
immediately opens a vent for other products - Says law states that by producing goods and
services - Firms create a total demand for goods and
services equal to what they have produced or more
simply - Supply creates its own demand
17Total Spending in a More Realistic Economy
- Does Says law also apply in a more realistic
economy? - In the real world
- Households dont spend all their income
- Rather, some of their income is saved or goes to
pay taxes - Households are not the only spenders in the
economy - Businesses and government buy some of the final
goods and services we produce - In addition to markets for goods and resources,
there is also a loanable funds market - Where household saving is made available to
borrowers in business or government sectors
18Some New Macroeconomic Variables
- Planned investment spending (IP) over a period of
time is total investment spending (I) minus
change in inventories over the period - IP I ? inventories
- Net taxes (T) are total government tax revenue
minus government transfer payments (unemployment
insurance, welfare payments, Social Security
benefits) - T total tax revenue transfers
- Household saving (S)
- Its often useful to arrive at household saving
in two steps - Determine how much income household sector has
left after payment of net taxes - Household sectors disposable income
- Disposable Income Total Income Net Taxes
- Part that is not spent is defined as (household)
saving (S) - S Disposable Income C
19Some New Macroeconomic Variables
- Total Spending in Classica
- In Classica, total spending is sum of purchases
made by household sector (C), business sector
(IP), and government sector (G) - Total spending C IP G
- Saving and net taxes are called leakages out of
spending - Amount of income that households receive, but do
not spend - There are also injectionsspending from sources
other than households - A governments purchases of goods and services
- Planned investment spending (IP)
- Total spending will equal total output if and
only if total leakages in the economy are equal
to total injections - Only if sum of saving and net taxes is equal to
sum of planned investment spending and government
purchases
20Flows in the Economy of Classica
Total Output (GDP) 7 trillion
Total Income 7 trillion
Consumption Spending (C) 4 trillion
Planned Investment Spending (Ip) 1 trillion
Government Purchases (G) 2 trillion
Net Taxes (T) 1.25 trillion
Household Saving (S) 1.75 trillion
21Figure 4 Leakages and Injections
Leakages
Injections
22The Loanable Funds Market
- Where households make their saving available to
those who need additional funds - Total supply of loanable funds is equal to
household saving - Funds supplied are loaned out, and households
receive interest payments on these funds (if the
funds are provided through stock market then?) - Businesses demand for loanable funds is equal to
their planned investment spending - Funds obtained are borrowed, and firms pay
interest on their loans - Budget deficit
- Excess of government purchases over net taxes
- Budget surplus
- Excess of net taxes over government purchases
- When government purchases of goods and services
(G) are greater than net taxes (T) - Government runs a budget deficit equal to G T
- When government purchases of goods and services
(G) are less than net taxes (T) - Government runs a budget surplus equal to T - G
23The Loanable Funds Market
- When the government runs a budget deficit, its
demand for loanable funds is equal to its
deficit. The funds are borrowed, and government
pays interest on its loans. - View of the loanable funds market
- The supply of funds is household saving
- The demand for funds is the sum of the business
sectors planned investment spending and the
government sectors budget deficit, if any.
24The Supply of Funds Curve
- Since interest is reward for saving and supplying
funds to financial market - Rise in interest rate increases quantity of funds
supplied (household saving), while a drop in
interest rate decreases it - Supply of funds curve
- Indicates level of household saving at various
interest rates - Quantity of funds supplied to the financial
market depends positively on interest rate - This is why the saving, or supply of funds, curve
slopes upward - Other things can affect savings besides the
interest rate, including - Tax rates
- Expectations about the future
- General willingness of households to postpone
consumption
25Figure 5 Supply of Household Loanable Funds
Saving (S) or Supply of Funds
B
5
A
3
1.5
1.75
26The Demand for Funds Curve
- When interest rate falls investment spending and
the business borrowing needed to finance it rise - Business demand for funds curve slopes downward
- What about governments demand for funds?
- Will it, too, be influenced by the interest rate?
- Probably not very much
- Government seems to be cushioned from
cost-benefit considerations that haunt business
decisions - Any company president who ignored interest rates
in deciding how much to borrow would be quickly
out of a job - U.S. presidents and legislators have often done
so with little political cost - Government sectors deficit and its demand for
funds are independent of interest rate - As interest rate decreases quantity of funds
demanded by business firms increases - While quantity demanded by government remains
unchanged - Therefore, total quantity of funds demanded rises
27Figure 6 Business Demand for Loanable Funds
A
5
B
3
Planned Investment (IP) or Business Demand for
Funds
1.5
1.0
28Figure 7 The Demand for Funds
29Equilibrium in the Loanable Funds Market
- In classical view loanable funds market is
assumed to clear - Interest rate will rise or fall until quantities
of funds supplied and demanded are equal - Can we be sure that all output produced at full
employment will be purchased?
30Figure 8 Loanable Funds Market Equilibrium
Total Supply of Funds (S)
5
E
Total Demand for Funds IP (G T)
1.75
31The Loanable Funds Market and Says Law
- As long as loanable funds market clears, Says
law holds - Total spending equals total output
- This is true even in a more realistic economy
with saving, taxes, investment and government
deficit - Heres another way to see the same result, in
terms of a simple equation - Loanable funds market clears ? S IP (G T)
- Rearranging this equation by moving T to left
side - Loanable funds market clears ? S T IP G
- Says law shows that total value of spending in
economy will equal total value of output - Rules out a general overproduction or
underproduction of goods in the economy - It does not promise us that each firm will be
able to sell all of the particular good it
produces
32Figure 9 An Expanded Circular Flow
1.75 Trillion
1.0 Trillion
0.75 Trillion
1.25 Trillion
33The Classical Model A Summary
- Began with a critical assumption
- All markets clear
- In classical model, government neednt worry
about employment - Economy will achieve full employment on its own
- In classical model, government neednt worry
about total spending - Economy will generate just enough spending on its
own to buy output that a fully employed labor
force produces
34Using the Theory Fiscal Policy in the Classical
Model
- Could government increase economys total
employment and total output by raising total
spending? Seems like an idea that should work?
..business firms might hire more workers and
produce more? - Two ideas for increasing spending come to mind
- Government could simply purchase more output
itself - More goods, like tanks and police cars, or more
services, like those provided by high school
teachers and judges - Government could cut net taxes, letting
households keep more of their income - So they would spend more on food, clothing,
furniture, new cars, and so on
35Fiscal policy in the CM
- Fiscal policy is a change in government purchases
or in net taxes - Designed to change total spending in the economy
and thereby influence levels of employment and
output - Idea behind fiscal policy sounds sensible enough
- But does it work?
- Not if economy behaves according to classical
model - Fiscal policy in classical model is completely
ineffective. It cant change total output or
total employment - It cant even change total spending
- Moreover Fiscal policy is unnecessary (?)
- since the economy achieves and sustains full
employment on its own
36Using the Theory Fiscal Policy With A Budget
Deficit
- What would happen if the government of
Classicawhich is running a deficitattempted to
increase employment and output by increasing
government purchases - Crowding out is a decline in one sectors
spending caused by an increase in some other
sectors spending - In classical model a rise in government purchases
completely crowds out private sector spending so
total spending remains unchanged - In classical model, an increase in government
purchases has no impact on total spending and no
impact on total output or total employment - Opposite sequence of events would happen if
government purchases decreased - Total spending and total output would remain
unchanged
37Figure 10 Crowding Out With An Initial Budget
Deficit
Total Supply of Funds (S)
7
B
D IP
A
C
H
5
DC
D2
D1
1.75
2.05
2.25
38Fiscal Policy With A Budget Surplus
- Total spending remains unchanged, and fiscal
policy is completely ineffective - Same conclusion we reached about fiscal policy
with a government budget deficit - Our exploration of fiscal policy shows us that,
in long-run - Government efforts to change total output by
changing government spending or taxes are
unnecessary and ineffective
39Figure 11 Crowding Out With An Initial Budget
Surplus
S2
S1
B
7
DIP
H
C
5
A
DC
Business Demand for funds (IP)
1.25
1.55
1.75