public and private sector behaviour
TRANSCRIPT
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Public and Private
Sector Behaviour
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
2
Outline
1. The role of expectations
2. Budget constraints
- Private sector
- Public sector
- Intertemporal budget constraint of the economy
- Ricardian equivalence
3. Private sector demand
- Consumption
- Investment
- Goods market equilibrium (IS curve)
This lecture follows chapters 5 and 6 of the textbook.
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
3
1. The role of expectations
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
4
Modern economic theory recognizes
that the central difference between
economics and natural sciences lies in
the forward-looking decisions made
by economic agents.
Evans, Honkapohja (2001)
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
5
Why are expectations important?
People make decisions thinking about their present and future consequences
Example: why do you study instead of going to work?
- Because studying is funny?
- Because you expect to earn more in the future?
Hence, to understand macroeconomics we should also look at intertemporal decision problems
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
6
How are expectations formed?
Alternative approaches
- Adaptive (e.g. Friedman 1956) – we look backwards:
Popular in the 1950’s-60’s. Now out of fashion –
allow for systematic mistakes
- Rational (Muth 1962, Lucas 1972) – we look forward:
Popular since 1970’s.
- Adaptive learning (Evans, Honkapohja 2001) – we
learn over time the true model
)|( 11 tt
e
t xEx
t
e
t xx 1
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
7
Rational expectations
Dominant approach since the 1980s
Advantage:
- Consistent with rational behaviour assumption
Disadvantage:
- Inconsistent with (part of) the empirical evidence
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
9
2. Budget constraints
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
10
Private sector budget constraint
Private sector = households + private enterprises
Enterprises are owned by households. So, private sector budget constraint can be represented by the household budget constraint.
Because households can borrow and lend, their budget constraint is intertemporal
Assume household lives for two periods, has endowment (y1, y2).
If it can lend/ borrow it can trade current vs. future consumption at the interest rate r.
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
11
Household budget constraint
Consumption tomorrow must equal income tomorrow
plus today’s savings with interest:
c2= y2+(1+r)(y1-c1)
or
c1+c2/(1+r)=y1+ y2 /(1+r)
Present value of consumption must equal present
value of income (wealth)
This is the intertemporal budget constraint which
determines the set of possible consumption baskets
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
12 Consumption today
Consum
ption t
om
orr
ow
0
= - 1+ rslope ( )
Endowment, wealth...
Endowments M, A and P for interest rate
r imply the identical wealth OB, and
identical consumption possibilities.
Y1
Y2
D
B
M (student, low Y1 today, high Y2 tomorrow)
(Professional athlete, high Y1
P today, low Y2 tomorrow)
A
Figure 5.01
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
13
Public sector budget constraint
The public sector is similar to the private
sector
- has income and expenditures,
- can save or borrow,
- has a budget constraint:
g1+g2/(1+r)= t1 + t2/(1+r)
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
14
Is the public sector budget constraint
binding?
The real world has more than two periods
That’s why the budget constraint of the government is difficult to see
But it binds. Two proofs:
1. Higher public debt causes higher interest rates – investors demand a risk premium (e.g. Ford, Laxton 1995).
2. Sometimes countries default. Examples:
- Russia 1998
- Argentina 2002
- Greece 2011
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© Oxford University
Press, 2012. All rights
reserved.
Primary Consolidated Budget Surpluses, 1970-2010
Figure 7.8 Primary Consolidated
Budget Surpluses, 1974-2009
Figure 7.8
Source: OECD, National Accounts
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
16
Public debt in the EU
Source: European Commission
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
17
Intertemporal budget constraint of
the economy
Adding up private and public sector budget constraints:
Private (with tax): c1+c2/(1+r)=(y1-t1) + (y2-t2) /(1+r)
Public: g1+g2/(1+r)= t1 + t2/(1+r)
Whole economy: c1+c2/(1+r)=(y1-g1) + (y2-g2) /(1+r)
Taxes disappear – the economy-wide constraint looks like the private sector constraint (with G expenditure instead of taxes)
Adding the government simply reduces private sector wealth by t1 + t2 /(1+r) = g1 + g2 /(1+r)
The present value of taxes or expenditure matters, not the distribution over time
If the government runs a deficit in period 1, people know that they will pay higher taxes in period 2. This reduces their wealth and thus consumption in both periods.
This is called Ricardian equivalence.
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© Oxford University
Press, 2012. All rights
reserved.
Con
sum
ptio
n t
om
orr
ow
0
Before Government Spending and Taxes
B
D
= 1+ rslope ( )
The original endowment, i.e.
before government spending
and taxes, is A.
Consumption today
Figure 7.9 (a)
Y1
Y2 A
The national wealth is 0B, the
present discounted value of A.
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© Oxford University
Press, 2012. All rights
reserved.
Con
sum
ptio
n t
om
orr
ow
0
With Government Spending and Taxes
B´
D´
B
D
= 1+ rslope ( )
A´
(Y1-G)
(Y2-G)
Deducting the present value of
government spending (equal to
the present value of taxes by
the government budget
constraint), we have private
wealth OB´ (= OB-B´B). For
simplicity we assume identical
G in both periods.
Consumption today
Figure 7.9 (b)
Y1
Y2 A
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Press, 2012. All rights
reserved.
Con
sum
ptio
n t
om
orr
ow
0
Ricardian Equivalence
B B´
D
D´
Y1
Y2 A
A´
(Y1-G)
(Y2-G)
= 1+ rslope ( )
The insight is that given the
present value of government
spending (i.e. the shift of private
wealth to D´B´), it doesn’t matter
for private wealth whether (i)
there are low taxes and a deficit
to be paid off later with higher
taxes or (ii) higher taxes now so
that taxes later are lower.
Consumption today
Figure 7.9 (c)
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
21
Ricardian equivalence - consequences
Decline of public savings is fully compensated by increase of private saving,
Public deficit/ debt does not impact on interest rates,
Fiscal stimulus not possible,
No twin deficits.
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
22
Does Ricardian equivalence hold?
Certainly not fully:
- public debt impacts on interest rates,
- fiscal stimulus usually works,
- in practice private savings compensate
probably not more than 50% of public
deficits.
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Press, 2012. All rights
reserved.
Figure 7.12
Sources: OECD, Economic Outlook
Ricardian Equivalence in the UK, 1970-2011
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The Effect of Fiscal Consolidation on the Current Account
John Bluedorn and Daniel Leigh
M.Brzoza-Brzezina:
Macroeconomics II - Introduction
to Macroeconomics
24
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Effect of public stimulus
Source: Nickel & Tudyka 2013
M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
25
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
26
Why does Ricardian equivalence not
hold?
People die, governments seldom do,
People are not always forward-looking,
Interest rates at which public and
private sectors borrow differ,
Households may be restricted to
borrow.
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Press, 2012. All rights
reserved.
Table 7.1
Source: Macrobond
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Press, 2012. All rights
reserved.
Public and Private Borrowing Rates in Italy
Figure 7.10
2007 - 2011
Sources: ECB; Banca d‘Italia
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reserved.
B
D
= 1+ rslope ( )
Consum
ption t
om
orr
ow
0
(a) Households Can Save, But Not Borrow
A
(Y1-G1)
(Y2-G2)
If households are constrained
from borrowing at all (but they
can still save), they can choose
only among the points along
segment AD.
Consumption today
Figure 7.11 (a)
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B
D
= 1+ rslope ( )
Consum
ption t
om
orr
ow
0
(b) The Government Can Borrow
A
(Y1-G1)
(Y2-G2)
A´ (Y2-T2)
(Y1-T1)
If the government is able to borrow at
the interest rate r the government
could reduce taxes today and raise
taxes in the future (to pay for the tax
saving this period plus interest).
This increases budget segment of
households to DA´.
Hence, timing of gov expenditure can
affect the private sector’s budget
constraint
Consumption today
Figure 7.11 (b)
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Press, 2012. All rights
reserved.
Consum
ption t
om
orr
ow
0
(c) Households Can Borrow
B
D
A
(Y1-G1)
(Y2-G2)
= 1+ rslope ( )
B´
= 1+ r´slope ( )
Consumption today
Figure 7.11 (c)
Households face a higher interest
rate (r‘) if they borrow than if they
save (r).
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B´´
= 1+ r´slope ( )
Consum
ption t
om
orr
ow
0
(d) Government Can Ease Borrowing Constraint
B´
D
A
(Y1-G1)
(Y2-G2)
= 1+ rslope ( )
A´ (Y2-T2)
(Y1-T1)
The government could reduce taxes
today and raise taxes in the future (to
pay for the tax saving this period plus
interest).
This increases budget segment of
households to DA´B´´ from DAB´.
Again, timing of gov expenditure can
affect the private sector’s budget
constraint
Consumption today
Figure 7.11 (d)
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Reasearch on Ricardian
equivalence
„We investigate the impact of fiscal stimuli at different levels of the government debt-
to-GDP-ratio for a sample of 17 European countries from 1970 to 2010. […] We find
that responses to government spending shocks exhibit strong non-linear behaviour.
While the overall cumulative effect of a spending shock on real GDP is positive and
significant at moderate debt-to-GDP ratios, this effect turns negative as the ratio
increases. The total cumulative effect on the trade balance is negative at first but
switches sign at higher levels of debt. Consequently, depending on the degree of
public indebtedness, our results accommodate long-run fiscal multipliers which are
greater and smaller than one or even negative as well as twin deficit and twin
divergence behaviour within one sample and time period.”
Nickel & Tudyka 2013 „Fiscal Stimulus in Times of High Debt Reconsidering
Multipliers and Twin deficits”
(Good reading for those interested in the topic)
M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
33
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
34
3. Private sector demand
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People choose
stable rather
than volatile
consumption
(R vs. M or A)
© Oxford University Press, 2012.
All rights reserved.
Optimal Consumption
Fig. 8.2
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Macroeconomics II - Public and
private sector behaviour
36
Consumption smoothing – consequences (1)
consumption is more stable than output (income)
0
1
2
3
4
5
6
1996
q01
1997
q01
1998
q01
1999
q01
2000
q01
2001
q01
2002
q01
2003
q01
2004
q01
2005
q01
2006
q01
GDP EU-25 Consumption EU-25
Source: Eurostat
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
37
We react differently to permanent and to
transitory shocks to income
we smooth income over the lifecycle
(Modigliani’s life cycle hypothesis)
Consumption smoothing –
consequences (2)
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Press, 2012. All rights
reserved.
Temporary vs. Permanent Income Change C
onsum
ption t
om
orr
ow
0
R´
A´´R´´
Y1
Y2
Y1´ B
D
A=R A´
B´ B´´
D´
Temporary: R to R´
Permanent: R to R´´
Fig. 8.3 (c)
Consumption today
Y2´
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Press, 2012. All rights
reserved.
Permanent vs. Temporary Shocks: Ireland and Germany
Fig. 8.4 (a)
Source: OECD Economic Outlook
2005 -
2011
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reserved.
Permanent vs. Temporary Shocks: Ireland and Germany
Fig. 8.4 (b)
Source: OECD Economic Outlook
2005-
2011
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Borrowing
Saving
Time
Income,
Consumption
0
Life-Cycle Consumption
Income
Consumption Permanent
income
Fig. 8.5
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Life-cycle in the data
M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
42
Source: Hammer 2015
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
43
What determines consumption demand?
Let us solve the consumers problem (very simplified)
Hence, today’s consumption depends not (only) on current income, but rather on wealth.
211
2111
2121
21
1
1
2
1
:_
0)1()1(
11
:___
)1/()1/(
..
lnln)(max
yr
yc
termsgrearrangin
yyrcr
r
c
yieldsatingdifferentiandngsubstituti
ryyrcc
ts
cccU
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Consumption and Net Wealth
300
400
500
600
700
800
900
1000
1100
1200
1300
1000 3000 5000 7000 9000
Net wealth (Euro bn.)
Co
ns
um
pti
on
( E
uro
bn
.)
Consumption and Disposable Income
300
400
500
600
700
800
900
1000
1100
1200
1300
400 600 800 1000 1200 1400
Disposable income (Euro bn.)
Co
ns
um
pti
on
(E
uro
bn
.)
Consumption, wealth and disposable income:
France, 1980-2002
Fig. 6.10
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Macroeconomics II - Public and
private sector behaviour
45
Consumption, income and wealth
In reality consumption depends stronger
on current income:
- problems with wealth estimation
(forward looking problem)
- borrowing constraints
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reserved.
Consum
ption t
om
orr
ow
0
Household With Credit Constraint
D
C
B
A
R
Fig. 8.8 (b)
Consumption today
With credit constraint, the
choice set is reduced.
As a result current
income (A) may
determine consumption
choice.
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
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Reaction function of consumption to
real interest rate hike in Poland
-1.5
-1.0
-0.5
0.0
0.5
5 10 15 20
Response of CONS to Cholesky
One S.D. RWIB1MEXP Innovation
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Macroeconomics II - Public and
private sector behaviour
48
Investment demand
Determinants of investment demand
- real interest rates
- economic growth
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Solve the firm’s problem
Π𝑡 = 𝑦𝑡 − 𝑟𝑡𝑘𝑡 −𝑤𝑡𝑙𝑡
𝑦𝑡 = 𝑘 𝑙𝑡1−𝛼
𝑡−1𝛼
Substitute and find optimum
𝛼𝑘 𝑙𝑡1−𝛼 − 𝑟𝑡 = 0𝑡−1
𝛼−1
𝛼𝑦𝑡𝑘𝑡−1
= 𝑟𝑡
© Oxford University Press, 2012.
All rights reserved.
The Optimal Capital Stock
Fig. 8.10
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Determinants of investment
𝑘𝑡−1 = 𝛼𝑦𝑡
𝑟𝑡 and 𝑘𝑡 = 𝛼𝐸𝑡
𝑦𝑡+1
𝑟𝑡+1
Ignoring depreciation:
𝑖𝑡 = 𝑘𝑡 − 𝑘𝑡−1
So that:
𝑖𝑡 = 𝛼 𝐸𝑡𝑦𝑡+1𝑟𝑡+1
−𝑦𝑡𝑟𝑡
Investment rises with output and declines
with the interest rate
M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
50
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
51
Reaction function of investment to
real interest rate hike in Poland
-8
-6
-4
-2
0
2
4
5 10 15 20
Response of INWYOY to Cholesky
One S.D. RWIB1MEXP Innovation
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
52
Enterprises tend to invest when they expect demand for their products to rise
Investment and economic growth (2)
80
90
100
110
120
130
100 101 102 103 104 105 106 107 108
PKB
na
kla
dy b
rutt
o n
a s
rod
ki tr
wa
le
80
90
100
110
120
130
96 97 98 99 00 01 02 03 04
PKB
Naklady brutto na srodki trwale
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
53
Goods market equilibrium (IS curve)
Deriving the goods market equilibrium we ignore investment and capital formation
The general equilibrium model we will construct later is designed to explain short- to medium term behaviour. Capital formation is rather a long term phenomenon.
Take consumption demand and impose market clearing condition c=y:
Current output depends positively on (expected) future output and negatively on the current real interest rate. This is the IS curve.
21
211
1
1
1
1
2
1
yr
y
yr
yc
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
54
IS curve
Originally comes from Hicks (1937) and
describes part of the Keynesian IS-LM model
r
Y
IS
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Takeaways Expectations matter for economic decissions. Standard
assumption: rational, but evidence mixed
Household consumption:
– Is the results of intertemporal optimization
– Depends on current and expected future income
– Depends on real interest rates
– HHs smooth consumption over the business cycle and over the life cycless
Ricardian equivalence:
– HHs internalize the public sectors budget constraint
– As a consequence only gov. expenditure matters, not the timing of taxation
– HHs increase savings in reaction to higher government deficyt
– But Ricardian equivalence holds only partially (~50%): • People are myopic
• People die or emigrate
• People are credit constrained
Business investment:
– Is the result of profit maximization
– Depends on expected economic growth and on real interest rates
M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
55
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M.Brzoza-Brzezina:
Macroeconomics II - Public and
private sector behaviour
56
Exercises
Derive IS curve
- under alternative utility function
assumptions
- with discount factor