View original document

The full text on this page is automatically extracted from the file linked above and may contain errors and inconsistencies.

clevelandfed.org/research/workpaper/index.cfm

Working P a ~ e r9213
RELATIVE PRICE MOVEMENTS IN DYNAMIC GENERAL
EQUILIBRIUM MODELS OF INTERNATIONAL TRADE
by David K. Backus, Patrick J. Kehoe, and Finn E. Kydland

David K. Backus is a professor of economics at
the Stern School of Business, New York
University; Patrick J. Kehoe is a professor of
economics at the University of Pennsylvania and
a consultant at the Federal Reserve Bank of
Minneapolis; and Finn E. Kydland is a professor
of economics at Carnegie-Mellon University,
Pittsburgh, and a research associate of the
Federal Reserve Bank of Cleveland. The authors
thank the National Science Foundation, the
Institute for Empirical Macroeconomics, and the
Center for Japan-U.S. Business and Economic
Studies faculty fellowship program for financial
support. They also thank Ronald Jones, Maury
Obstfeld, and Chris Stefanadis for helpful
comments.
Working papers of the Federal Reserve Bank of
Cleveland are preliminary materials circulated
to stimulate discussion and critical comment.
The views stated herein are those of the authors
and not necessarily those of the Federal Reserve
Bank of Cleveland or of the Board of Governors
of the Federal Reserve System.
November 1992

clevelandfed.org/research/workpaper/index.cfm

ABSTRACT

We examine the behavior of international relative prices from the perspective
of dynamic general equilibrium theory, with particular emphasis on the
variability of the terms of trade and the relation between the terms of t r a d e
and net exports.
We highlight aspects of the theory t h a t a r e critical in
determining these properties, contrast our perspective with those associated
with the Marshall-Lerner condition and the Harberger-Laursen-Metzler effect,
and point out features of the data that have proved difficult t o explain
within existing dynamic general equilibrium models.

clevelandfed.org/research/workpaper/index.cfm

1

Introduction
Relative

prices

are

a

central

feature

of

both

international trade and open-economy macroeconomics.

the

pure

theory

of

Although the emphasis

differs in the two branches of international economics, t o a great extent the
same theory underlies theoretical and empirical work in each.
of

dynamic general equilibrium theory,

or international

Applications

real business

cycle

theory, continue this tradition by extending, a t the aggregate level, several
of the features of

static trade theory t o dynamic and stochastic settings.

What these applications offer, we think, is a deeper understanding of

the

dynamics of trade and relative prices.
The Marshall-Lerner condition is, without question, the most common link
between trade theory and international macroeconomics.

In trade theory, this

elasticity condition on import demand functions determines the direction of
many comparative statics exercises and serves as a stability condition on an
otherwise
process

static
will

theory,

succeed

macroeconomics,

the

telling
in

same

us

whether

establishing
condition

is

a

disequilibrium

equilibrium.
used

to

In

adjustment
international

establish

a

positive

association between the trade balance and the terms of trade or real exchange
rate.

This is the level a t which the theory is presented in most textbooks

and,

indeed,

in the

popular

Mundell-Fleming

and

Dornbusch

macroeconomic

models of open economies.
The macroeconomic branch of international economics has also developed
insights that a r e largely independent of the theory of trade.
approach focuses on the
and the balance of trade.
theory

is

its

suggestion

accounting relation

The absorption

connecting saving,

investment,

What distinguishes this work from static trade
that

the

trade

balance,

or

the

closely

related

current account, reflects the dynamic decisions by agents t o lend or borrow
in international capital markets.

A critical development f o r understanding

clevelandfed.org/research/workpaper/index.cfm

t h e relation between t r a d e and relative prices i s t h e recognition t h a t any
dependence of t h e t r a d e balance on t h e terms of t r a d e implies, as a m a t t e r of
accounting,

a

similar

relation

with

international

borrowing

and

lending.

This connection was noted by Harberger (1950) and Laursen and Metzler (1950)
and l a t e r incorporated by Obstfeld (1982) and Svensson and Razin (1983) into
explicitly dynamic theories

of

t h e balance

of

trade.

These l a t e r papers

emphasize t h e influence of t e r m s of t r a d e movements on permanent income, and
hence on saving.

They argue t h a t persistent changes in t h e t e r m s of t r a d e

have l a r g e r income e f f e c t s t h a n transitory changes, and t h u s give r i s e t o
potentially different relations between t h e t r a d e balance and t h e terms of
trade.

The

effect,

in

their

analysis,

is

a

comparison

between

two

deterministic equilibria.
We approach t r a d e and relative price dynamics f r o m a somewhat different
theoretical tradition, t h a t of dynamic general equilibrium theory.

Like much

of s t a t i c t r a d e theory, we use competitive consumers and producers.
t h a t work, however, our theory i s explicitly dynamic.

Unlike

And unlike t h e modern

approach t o t h e Harberger-Laursen-Metzler e f f e c t , we consider not comparisons
between

different

stochastic

deterministic

theoretical

equilibria,

economies.

We

but

properties

consider

in

the

experiment t h a t applied economists consider in t h e data:
between

trade

Somewhat t o

and
our

relative

surprise,

price
this

variables

approach

along

leads

to

an

of

equilibria

theory

the

in

same

t h e correlations
equilibrium

substantially

path.

different

views of t r a d e and price behavior than suggested by earlier work.
The application of

dynamic general equilibrium theory t o international

t r a d e h a s also led, in a rapidly growing number of papers, t o attempts t o
quantify t h e theory's properties and compare them t o properties of national
economies.

These a t t e m p t s have led t o a clearer understanding of

which

f e a t u r e s of t h e d a t a can be accounted f o r by t h e present s t a t e of theory and

clevelandfed.org/research/workpaper/index.cfm

which

remain

predictions

anomalous.

than

qualitative

This

quantitative

theory

and helps

approach

generates

sharper

t o focus f u r t h e r theoretical

work on clearly defined issues.
We

elaborate

on

the

twin

themes

of

theoretical

development

and

We s t a r t , in section 2, by

quantitative properties in t h e r e s t of t h e paper.

documenting some of t h e salient properties of aggregate t r a d e and relative
prices

a number

for

explicit

of

t h e o b j e c t s of

industrialized
interest

countries.

in theoretical

These

properties

make

economies and serve as a

basis of comparison with t h e theory.
We develop t h e theory in a series of two-country worlds, highlighting as
we go t h e

roles played

by

d i f f e r e n t theoretical

features.

Section 3 i s

devoted t o a n exchange economy in which each country specializes in a single
traded

good.

Here,

the

variability

of

relative

prices

and

between prices and t r a d e are governed by a single parameter:
of substitution between foreign and domestic goods.

the

relation

t h e elasticity

Some of t h e quantitative

properties of t h i s economy change when we consider preferences t h a t are not
additively

separable

between

consumption of home goods.
4.

foreign

and

domestic

goods

and

that

favor

This aspect of t h e theory i s developed in section

We find, among o t h e r things, t h a t agents' risk aversion plays a r o l e in

both t h e dynamics of t r a d e and prices and t h e relation between these t w o
variables.
In section 5, we compare t h i s theory with alternatives based on t h e
Marshall-Lerner condition and t h e Harberger-Laursen-Metzler
that

our

elasticity

condition

is

not

related

to

effect.

the

condition, which i s always satisfied in our symmetric economy.
t o t h e Harberger-Laursen-Metzler

effect,

we find t h a t

We show

Marshall-Lerner
With respect

t h e persistence

of

shocks i s orthogonal t o t h e relation between relative prices and t h e balance
of trade:

f o r given preference parameters, t h e correlation between t r a d e and

clevelandfed.org/research/workpaper/index.cfm

prices is the same whether price changes last one period o r one hundred.
both

comparisons,

dynamic general equilibrium theory

provides

a

In

different

perspective on trade and price fluctuations than does earlier work.
In the
structure

remaining

that

change

theory's predictions.

sections,

we consider

extensions of

the theoretical

some of

i t s quantitative features and

broaden the

In section 6, we explore shocks t o government spending

a s well a s t o aggregate endowments.

A s one might expect, this extension has

the potential t o change equilibrium comovements considerably.

We find, f o r

example, that the sign of the relation between the t r a d e balance and the
terms of trade depends on the relative sizes of shocks t o endowments and
government spending, a s well a s on the elasticity of substitution.
In section 7, we embed the exchange structure of earlier sections into
an economy with endogenous labor supply and capital formation.
element here is capital formation.
dynamics of trade now reflect,
physical

investment.

The

The critical

With this modification, we find that the

t o a large extent, cyclical fluctuations in
most

striking

result

is

an

asymmetric

cross-correlation

function f o r the trade balance and the terms of

which

the

we

label

S-curve.

This feature

does not

arise

in

trade,

exchange

economies, whereby construction investment is zero and the cross-correlation
function is symmetric.

In this sense, the dynamics of capital formation play

an important role in connecting the dynamics of the trade balance and the
relative price of foreign t o domestic goods.
We conclude with a few remarks on the strengths and weaknesses of
existing

dynamic

general

equilibrium theories

of

international

trade,

and

suggestions f o r directions the theory might take in the future.

2

F i r s t Look a t t h e Data
Since the ultimate objective of our theory is t o account f o r empirical

clevelandfed.org/research/workpaper/index.cfm

regularities, we start by looking at some of t h e properties of international
relative prices.
denoted p,

We focus here on t h r e e variables.

i s t h e r a t i o of

The t e r m s of

t h e import price deflator t o t h e export price

deflator, both taken f r o m national income and product accounts.
denoted nx,

i s t h e r a t i o of

output in current prices.
on t h e country,

trade,

exports minus imports,

Net exports,

in c u r r e n t prices,

to

Real output, denoted y, i s GDP o r GNP, depending

in base-year

(generally 1985).

prices

All t h r e e variables

a r e constructed with d a t a taken from t h e OECD's Quarterly National Accounts.
In table 4.1 we r e p o r t various properties of
t h r e e countries:

t h e t e r m s of

trade f o r

Japan, t h e United Kingdom, and t h e United States.

s t a t i s t i c s r e f e r t o Hodrick-Prescott

filtered variables,

of t r a d e and r e a l output a r e logarithms.

These

and both t h e t e r m s

Many of t h e same properties a r e

reported in Backus, Kehoe, and Kydland (1992b) and Blackburn and Ravn (1991)
for

additional

developed

countries

and

in

Mendoza

(1992) f o r

developing

The sample period in table 4.1 r u n s f r o m 1955:2 t o 1989:4, which

countries.

enables us t o look separately at t h e periods before and a f t e r t h e collapse of
Bretton Woods.
We see, f o r a s t a r t , t h a t movements in t h e t e r m s of t r a d e have been both
variable

and

persistent.

The

standard

deviation

of

terms

of

trade

f1uc;uations

ranges f r o m 2.71 percent in t h e United Kingdom t o 5.97 percent

in Japan.

Both here and in our earlier paper, variability of t h e t e r m s of

t r a d e i s considerably

larger

in

Japan

than

in

other

countries.

We

are

unsure, at t h i s point, how much of t h i s additional variability reflects t r u e
relative price movement and how much has t o do with differences in t h e manner
in which t r a d e prices a r e constructed.

Both Alterman (1991) and Graboyes

(1991) r a i s e questions concerning t h e quality of c u r r e n t t r a d e prices in t h e
United States, and these problems may be g r e a t e r in earlier periods and other
countries.

Alterman (1991) estimates t h a t improved price d a t a exhibit about

clevelandfed.org/research/workpaper/index.cfm

30 percent less variability t h a n those reported here.

Nevertheless, we a r e

probably on s a f e ground in claiming substantial variability of t h e t e r m s of
trade

in

all

countries.

Persistence

is

evident

in

the

autocorrelations,

Table 4.1 also verifies t h a t

which a r e generally in t h e neighborhood of 0.8.

t h e r e h a s been much more variability of t h e t e r m s of t r a d e since t h e advent
of floating exchange r a t e s than before, a f e a t u r e s t r e s s e d by Mussa (1986)
f o r r e a l exchange r a t e s ( r a t i o s of consumer price indexes converted at spot
exchange r a t e s ) .

Standard deviations of t h e t e r m s of t r a d e a r e typically t w o

t o t h r e e times l a r g e r in t h e l a t t e r period.
We also include, in table 4.1, correlations of t h e t e r m s of t r a d e with
net exports and r e a l output.
coherence across periods,
and

net

exports

have

With respect t o net exports, we find g r e a t e r

but little across countries.

generally

been

positively

The t e r m s of t r a d e

correlated

in

S t a t e s and negatively correlated in Japan and t h e United Kingdom.
table 4.2, which covers t h e post-Bretton

the

United

We s e e in

Woods period f o r 10 countries, t h a t

t h e United S t a t e s i s an outlier in t h i s regard:

The correlation between t h e

t r a d e balance and t h e t e r m s of t r a d e i s negative f o r every other country.
With respect t o output, t h e r e h a s been no regularity in t h e correlation with
t h e t e r m s of t r a d e , either over time o r across countries.
The contemporaneous correlation between net e x p o r t s and t h e t e r m s of
t r a d e f a i l s t o capture a n important regularity t h a t appears when we examine
t h e complete cross-correlation

function:

t h e correlations, t h a t is, between

pt and n ~ ~ f +
o r ~various
,
leads and lags k.
r e f e r s t o k=O.

The contemporaneous correlation

For positive k t h e correlations pertain t o net exports and

p a s t prices, and f o r negative k t h e reverse.

We find f o r Japan and t h e

United Kingdom t h a t t h i s function h a s an asymmetric S shape, which we call
t h e S-curve.

For Japan and t h e United Kingdom, t h i s f e a t u r e appears not only

in t h e postwar period as a whole, but in t h e pre-

and post-Bretton Woods

clevelandfed.org/research/workpaper/index.cfm

subperiods as well.

For t h e United States, the same p a t t e r n is evident only

in the earlier period.

Our earlier paper (Backus, Kehoe, and Kydland, 1992b,

figure 1) documents t h i s pattern in eight of eleven countries.
In t h e remainder of t h e paper, we examine these properties from the
perspective

of

a

series

of

successively

more

complex

dynamic

general

equilibrium models, bringing additional d a t a t o bear when t h e theory suggests
it.

For now, we note t h a t t h e t e r m s of t r a d e has been highly variable and

persistent in all t h r e e countries, t h a t i t s correlation with net exports i s
generally negative,

and t h a t t h e cross-correlation

function f o r net exports

and t h e t e r m s of t r a d e is often asymmetric (the S-curve property).

3

A Dynamic Exchange Economy

One of

the

simplest dynamic general equilibrium models of

economy has two countries t h a t t r a d e specialized endowments.
from

an

initial

date

0

to

a

terminal

date

T,

possibly

a world

Let time t r u n
infinite.

The

evolution of this endowment i s stochastic, given by a "Debreu tree" t h a t we
describe in notation adapted from Lucas (1984).

The s t a t e zL, a n element of

t
t h e s e t Z , denotes t h e history of the economy from d a t e 0 through t.
t
of these possible s t a t e s occurs with a probability n ( z 1.

Each

Country 1, which

we call the home country, is endowed with a stream of positive quantities of
the

home

Likewise,

good,
country

denoted
2,

the

t
{y (z 1)
1
foreign

or,

in

country,

shorthand
is

notation,

endowed

with

simply
the

(yl).

positive

sequence (y 1 of quantities of t h e foreign good. We denote the prices of t h e
2
t
t
t
domestic and foreign goods in s t a t e z by ql(z
and q2(z 1.
As in section

t
t
t
2, we define t h e t e r m s of trade, p ( z 1 = q ( z 1/q (z 1, as t h e relative price
2
1
of imports t o exports.
Each country i s represented by a single consumer, who stands in f o r a
large number of like agents.

The preferences of t h e consumer of country i

clevelandfed.org/research/workpaper/index.cfm

a r e characterized by the expected utility function

with O<p<l, U(c) = cl-'/(l-'),
parameter.

We r e f e r t o

and p O .

a s the risk aversion

Both agents consume composites of the foreign and domestic goods,

described by the Armington aggregator functions,
c (a b )
1 1' 1

=

G(al,bl),

c (b , a )
2 2 2

G(b2,a2),

=

with
1-a
1-a l/(l-a)
[wa
+ b
1
,

G(a,b) =

where a. and b. a r e the quantities of the domestic and foreign good consumed
1

1

by the agent

of

country

i.

Thus,

the

agents

of

each country consume

combinations of foreign and domestic goods, a s expressed in the function G.
This

theoretical

device,

due

to

Armington

(19691,

computable s t a t i c general equilibrium trade models.

is

widely

used

in

In this economy i t is

equivalent t o giving consumers preferences over foreign and domestic goods
directly.

The

two

parameters,

substitution and shares of
cr=l/a.

a>O

and

w>O,

govern

the

foreign and domestic goods.

elasticity

of

The elasticity is

With w=l, the two consumers have identical preferences, and with w>l

they exhibit a preference f o r home goods:

If home and foreign goods sell f o r

the same price, agents consume more of the home good than the foreign good.
The budget constraint of the domestic agent is

The foreign agent faces an analogous constraint.
A competitive equilibrium

quantities

( a b. 1 and prices
i' 1

in this economy consists of
(qi) such that

state-contingent

( i ) consumers maximize utility

clevelandfed.org/research/workpaper/index.cfm

given prices and budget constraints and (ii) quantities s a t i s f y t h e resource
constraints,

f o r each s t a t e z
Negishi-Mantel

t

.

We find i t convenient t o compute a n equilibrium using t h e

algorithm in which, f o r any initial distribution of resources,

a competitive allocation i s associated with a P a r e t o optimum.
i s t h e solution t o a
welfare

( A ,A ),
1 2

weights

maximize C.A.u
1 1

problem of t h e form:
choose

quantities

For

some choice of

(a a b b )
1' 2' 1' 2

subject t o t h e resource constraints.

i'

Each optimum

in

each

positive
state

to

The supporting prices

can then be identified with t h e Lagrange multipliers on t h e constraints o r
derived

from

describes

consumers'

this

first-order

procedure

in

a

conditions.

similar

context

Backus
and

(1992,

section 2 )

discusses

alternative

decentralization schemes.
For t h e optimum problem, l e t u s denote t h e Lagrange multipliers on t h e
resource constraints in s t a t e z
foreign goods, respectively.

t

t
t
by ql(z 1 and q2(z ) f o r t h e domestic and

The Lagrange multipliers correspond t o prices

in t h e associated competitive equilibrium.
price

functions

t
t
qi(z 1 = / 3 t n ( z t ) ~ i ( z1,

by

Qi

If, f o r each i, we define spot
then

the

optimum

problem

t
s e p a r a t e s into a number of identical problems, one f o r each s t a t e z , of t h e
form

max
{a ,bi}
subject t o t h e
state are

t

t

t

resource

constraints.

t

/3 n ( z 1 {AIU(G[al(z ),bl(z 11)

+

t
t
A2U(G[b2(z 1,a2(z 11))

The f i r s t - o r d e r

conditions f o r each

clevelandfed.org/research/workpaper/index.cfm

t
t
t
t
t
The t e r m s of t r a d e i s p(z 1 = q ( z )/q ( z 1 = Q ( z )/Ql(z ).
2
1
2
In

this

preferences,

section,
w=l,

for

we
which

restrict
the

ourselves

analysis

can

to

the

be

done

case

of

identical

analytically.

The

equilibrium allocation i s then

f o r countries i=1,2, with consumption s h a r e s s = hil/'/,Y
i
one.

.A!/'
J J

t h a t sum t o

Backus (1992) describes how t h e welfare weights, and hence t h e shares,

a r e related t o t h e endowments.

The properties of interest, however, do not

depend on t h e choice of weights, s o we can skip t h i s additional step.

The

supporting prices a r e , up t o a f a c t o r of proportionality,

and the equilibrium t e r m s of t r a d e i s

The t r a d e balance in country 1 is, in units of t h e domestic good,

In equilibrium, t h e r a t i o of t h e t r a d e balance t o output ( t h e form of t h e
t r a d e variable used in table 4.1) i s

Along any equilibrium path f o r this economy t h e welfare weights,

hi,

are

2

constant.

The consumption shares, s a r e functions of t h e welfare weights
i'

clevelandfed.org/research/workpaper/index.cfm

alone, so they a r e constant as well.

Thus, fluctuations in both t h e t r a d e

balance and t h e t e r m s of t r a d e a r e driven, along any equilibrium path, only
by movements
prices
y2/y1,

and

in t h e endowment

quantities

y2/y1.

ratio,

a r e functions of

a

In t h i s

sense,

equilibrium

single s t a t e variable,

the

ratio

and a r e t h u s indirectly related t o each other.
Although t h e theory i s f a i r l y simple, we can s t a r t t o compare some of

i t s properties with those of t h e d a t a

--

in particular, t h e variability and

persistence of t h e t e r m s of t r a d e , p, and t h e correlation of t h e t e r m s of
t r a d e with n e t exports.
variability
cr=l/a.

of

Clearly, t h e variability of

t h e endowment ratio,

y2/y1,

p i s governed by t h e

and t h e substitution

parameter,

A given amount of variability of t h e endowment r a t i o can produce as

much price variability as we like if cr i s small enough.

As a n example,

consider t h e standard deviation of t h e US t e r m s of t r a d e reported in table

3 percent, f o r t h e period as a whole.

4.1:

This r e f e r s t o t h e s t a n d a r d

deviation of t h e Hodrick-Prescott f i l t e r e d logarithm.

The standard deviation

of t h e f i l t e r e d logarithm of t h e r a t i o of Japanese t o US output i s about 2.2.
To generate t h e amount of price variability we see in t h e United S t a t e s ,
then, we need an elasticity of about cr=0.73 (since 2.2/0.73=3.01.

This i s

only a rough calculation, since t h e d a t a r e f e r t o a world with more t h a n one
country and in which a large p a r t of t h e variability of output appears in
investment, which i s obviously absent here.
played

by

variability.

the
As

elasticity

a

rule,

of
the

But i t i s suggestive of t h e role

substitution
theory

can

in

generating

produce

any

relative

amount

of

price
price

variability we like if t h e elasticity of substitution i s a f r e e parameter.
With

regard

to

persistence,

the

terms

autocorrelation properties of t h e endowment ratio.
the

autocorrelation

of

the

Japan/US

output

ratio

of

trade

inherits

the

To continue our example,
(the filtered

logarithm,

t h a t is) i s 0.7, s o the autocorrelation of t h e t e r m s of t r a d e , in our theory,

clevelandfed.org/research/workpaper/index.cfm

is also 0.7.
table

4.1,

This is slightly less than we see f o r t h e US t e r m s of t r a d e in
but

the

discrepancy

is

not

large,

either

economically

or

statistically.
The final issue concerns t h e relation between t h e t r a d e balance and t h e
t e r m s of trade.

The contemporaneous relation is summarized by

Proposition I.

Let o=l in t h e Armington aggregator, G.

Then t h e relation

between t h e t r a d e balance, n x /y
and t h e t e r m s of t r a d e , p, is governed by
1 1'
c=l/a,

t h e elasticity of substitution between foreign and domestic goods.

c > l , t h e t w o variables

a r e positively related;

if

If

6 1 , they a r e negatively

related.

More

precisely,

consider

x1=y'/y'
with x > x l .
2 1'
ratio, p < p l .

two

states

with

endowment

ratios

Since p i s a decreasing function of t h e endowment
If c > l , then nx/y < nx1/y'.

Now consider the t r a d e balance.

In t h i s case, t h e s t a t e with higher p also has higher nx/y
variables

are,

in

this

x=y /y
and
2 1

sense,

positively

related.

If

and t h e t w o

c<l, the

reverse

is

true.

A similar result is implicit in Stockman and Svensson (1987, section

5.3).

If c = l , t h e t r a d e balance is constant, as noted recently by Cole and
(1991).

Obstfeld
correlation

is

Except

either

+1 o r

for
-1,

nonlinearities
unless

c=l,

and
when

nonstationarities,
the

trade

the

balance

is

constant and t h e correlation i s not defined.
The dynamics of t h e relation between t r a d e and prices, like t h e dynamics
of prices, a r e determined completely by t h e dynamics of t h e endowment ratio.
Except

for

nonlinearities

and

nonstationarities,

the

cross-correlation

function f o r t h e t r a d e balance and t h e t e r m s of t r a d e is t h e same as t h e
autocorrelation function of t h e endowment ratio.
t h e logarithm of
Then if

the endowment

c > l , t h e cross-correlation

By way of example, suppose

r a t i o is AR(l), with autocorrelation

p>O.

function f o r the t r a d e balance and t h e

clevelandfed.org/research/workpaper/index.cfm

t e r m s of t r a d e i s tent-shaped:
correlation between p

t

and nx

The contemporaneous correlation i s +1 and t h e
t+k

is p l k ' .

If c < l , t h e function i s V-shaped.

Even with o t h e r autocorrelation patterns,

t h e cross-correlation function will

be symmetric since t h e autocorrelation function is.
therefore,

i s incapable of

The exchange economy,

reproducing t h e asymmetric correlation functions

pictured in f i g u r e 4.1.

4

P r e f e r e n c e f o r Home Goods
When consumers in t h e t w o countries have preferences t h a t f a v o r t h e i r

respective home goods (w>l in t h e Armington aggregator GI, t h e behavior of
t r a d e and prices changes somewhat.

When preferences f o r domestic and foreign

goods a r e n o t additively separable, we find t h a t t h e r i s k aversion p a r a m e t e r ,
7 , a s well

a s t h e elasticity of

goods, c=l/a,

substitution between foreign and domestic

plays a role in t h e relation between t h e t r a d e balance and t h e

t e r m s of t r a d e .
The simplest case i s y=a:

risk aversion

( 7 ) i s t h e inverse of

substitution

elasticity f o r foreign and domestic goods (c=l/a).

restriction,

preferences,

between

the

considerably.

foreign

including
and

the

domestic

aggregator,
goods,

are

additively

simplifying

the

With t h i s
separable

the

analysis

We compute an equilibrium, as before, f r o m an optimum.

The

r e a d e r may verify t h a t t h e equilibrium allocations, f o r countries i=1,2, a r e

a
a
where t h e consumption shares, s 1 = (ohl)1/~[(whl)1/'+h~'7~, s2 = 1-sa sb =
1' 1
b
b
1/'/[~11/'+(w~2)1/'l,
and s = 1-5
a r e constant along any equilibrium
A1
2
1'
path.

The only difference f r o m t h e symmetric case i s t h a t t h e consumption

s h a r e s now d i f f e r across goods, with l a r g e r values of w leading t o l a r g e r
a
s h a r e s of home good consumption, s and sb
1
2'

The supporting prices are

clevelandfed.org/research/workpaper/index.cfm

so the equilibrium terms of trade is

A s before, the relative price p is driven by the endowment ratio.

The only

change is the factor of proportionality, which does not affect the properties
of the logarithm of p.
by

the

variability

of

The variability of the terms of trade is determined
the

endowment

ratio,

y2/y1,

and

the

elasticity

of

substitution, cr=l/a.
The t r a d e balance f o r country 1 in this economy, expressed a s a ratio t o
domestic output, is

We can see that preference f o r home goods (w>l) has the effect of damping
fluctuations in the balance of trade, since larger values of w imply smaller
Comovements, however, do not change:

values of sb
1'

The sign of the effect

of the endowment ratio on the balance of t r a d e once more hinges on whether
cr=l/a

is

greater

parameters.

or

Thus,

less
the

than

one

properties

and

does

described

not

in

the

depend

on

previous

any

other

section

for

identical preferences (w=l) apply t o this economy a s well.
It should be clear, then, that any influence of
parameter,

w,

on

price

behavior

between domestic and foreign goods
allocation
sign of
solution,

of

goods between

a-y.
but

straightforward.

intuition

--

operate

nonseparabilities

influenced, in this

conditions do not

behind

through

different values of a and y.

countries is

The first-order
the

must

the home preference

the

admit a

equilibrium

The

case, by

the

simple analytic

allocation

is

fairly

A s before, the variables of interest a r e functions of the

clevelandfed.org/research/workpaper/index.cfm

endowment r a t i o , x=y /y
2 1'

In s t a t e s with high values of x, t h e r a t i o s of

foreign t o domestic good consumption, b./ai,
1

r a t i o , c /c
2

of

1'

a r e also high:

t h e endowment r a t i o x.

and t h e aggregate consumption

They a r e increasing functions, in other words,
Neither

property is surprising:

If

t h e r e is

relatively more of t h e foreign good, then in equilibrium both agents consume
relatively

more,

and

aggregate

consumption

favors

the

country

preferences weight t h e foreign good more (country 2, since w>l).

whose

In simple

terms, let t h e foreign and domestic goods be bananas and apples, and suppose
the

foreign

apples.

agent

prefers

bananas

(w>l) and

the

domestic

agent

prefers

Then t h e two statements a r e , f i r s t , t h a t in s t a t e s with relatively

more bananas, both agents consume relatively more bananas than apples and,
second, t h a t aggregate consumption by t h e foreign agent, who h a s a s t r o n g e r
preference f o r bananas, r i s e s proportionately more t h a n consumption by t h e
domestic agent.

Proofs of

both of

these statements a r e included in t h e

appendix.
From t h i s s t a r t i n g point, w e can deduce t h e e f f e c t s on t h e relative
price of t h e foreign good and t h e balance of trade.
From t h e first-order

conditions, reported

Consider t h e price.

in t h e previous section, w e see

t h a t t h e t e r m s of t r a d e satisfies the relations

where f o r convenience w e have dropped explicit dependence of variables on t h e
state, z

t

.

Since b /a and b2/a2
1 1

a r e increasing functions of t h e endowment

r a t i o x , t h e t e r m s of t r a d e is a decreasing function.
t h e relative

supply of

t h e foreign good

Thus, a n increase in

lowers i t s relative price.

With

somewhat g r e a t e r e f f o r t we can characterize t h e magnitude of t h e decline.
The f i r s t s t e p i s t o r e l a t e t h e endowment r a t i o t o bl/al.
constraints imply

The resource

clevelandfed.org/research/workpaper/index.cfm

b
s1=bl/y2

where

is

the

(possibly

state-dependent)

share

of

foreign

good

Thus, with 0 1 , the proportional

consumption by the agent of country 1.

change in b /a can be either greater o r less than the proportional change in
1 1
x, depending on whether sb increases o r decreases with x.
1

The second step

follows from the first-order conditions f o r the foreign good:

Since

c /c
2 1

is

an

increasing

function

of

the

endowment

ratio,

sb
1

is

increasing in x if p a , decreasing if ;r<a, and constant if ;r=a (this being
the additively separable case described earlier).

Thus, the (absolute value

of the) slope of the relation between the logarithms of the terms of trade,
p, and the endowment ratio, x, is greater than a if y>a, less than a if y<a,
and equal t o a ( a s we've already seen) if y=a.
risk

aversion

tends

to

increase

the

variability

Other things equal, greater
of

the

terms

of

trade

relative t o t h a t of the endowment ratio.
The contemporaneous relation between the trade balance and the terms of
t r a d e is characterized by

Proposition 2.
positive

number

Let w>l (preference f o r home goods).
cr*

such

that

if

cr>cr*,

the

trade

Then there exists a
balance,

nx /y
1 1'

is

positively related t o the terms of trade, p, and if crccr*, the two variables
a r e negatively related.

Furthermore, if ;r>l, then cr*<l.

Thus, the risk aversion parameter, ;r, has an influence on comovements between
t h e trade balance and the terms of trade.

The proof

consists largely of

expressing the ratio of the trade balance t o output in a convenient form.

As

in Proposition 1, both the trade balance and the terms of trade a r e monotonic

clevelandfed.org/research/workpaper/index.cfm

functions of t h e endowment r a t i o x=y /y
2 1'
parameter values, decreasing in x.

a
With w=l, sl i s constant.

The t e r m s of t r a d e is, f o r a l l

As f o r t h e t r a d e balance, we let

Since bl/al

is, as we have shown, increasing in

t h e endowment r a t i o x=y /y
t h e proposition follows immediately with cr*=l.
2 1'
a
With w>l, t h e dependence of s on x introduces an additional element of
1
dependence on x.

If ;r>l and a<;r, sa i s increasing in x.
1

t r a d e balance i s decreasing in x.
parameters,

Thus, f o r a s 1 t h e

Since t h e solution i s continuous in t h e

t h i s i s t r u e f o r values of a slightly g r e a t e r than 1 a s well.

For l a r g e values of a , however, t h e t r a d e balance is increasing in x , as we
show

in

cr*=l/a*<l

t h e appendix

(result [A41).

Thus,

there

a r e numbers a*>l and

t h a t divide regions of positive and negative comovement between t h e

t r a d e balance and t h e t e r m s of trade.
In s h o r t , t h i s economy i s much like t h a t of t h e previous section.

Its

similarities and differences a r e illustrated by t h e following example.

Example.
1 2 1 2

Let

there

be

two

s t a t e s , with

unconditional

probabilities

(Nonlinearities a r e irrelevant here, since t w o points c a n always

be connected by a s t r a i g h t line.)

Let t h e aggregate endowments (y y
1' 2

of

t h e domestic and foreign goods be (l+e,l-E) in s t a t e 1, (I-e,l+e) in s t a t e 2,
with e>O.

Thus, t h e standard deviations of y

1

and y

2

a r e e and t h e standard

is, f o r small e ,
deviation of t h e logarithm of t h e endowment r a t i o y /y
2 1
approximately 2e.

The transition probabilities between s t a t e s i and j a r e

The persistence parameter p governs t h e autocorrelation function f o r

any

random variable adapted t o the s t a t e , with t h e k-order autocorrelation equal
to p

k

.

clevelandfed.org/research/workpaper/index.cfm

Case 1:

identical preferences (w=l).

The t e r m s of t r a d e i s

- ~ state 1
which equals [ ( 1 + ~ ) / ( 1 - ~ ) 1 in

The

is, f o r small c ,

approximately

With c=0.05 and a=5, t h e standard deviation i s 0.500.

The r a t i o of

s t a n d a r d deviation of
a(2c).

and [ ( l - c ) / ( l + c l ~ - ~in s t a t e 2.

t h e logarithm

of

p

t h e t r a d e balance t o output is

Thus, f o r cr=l/a<l, t h e correlation between p and t b is -1,
correlation i s +l.

and f o r cr>l t h e

For a = l , t h e t r a d e balance is zero in both s t a t e s and t h e

correlation i s not defined.

Note t h a t t h e persistence parameter, p, h a s no

bearing on t h i s correlation.

The cross-correlation

function f o r t h e t r a d e

balance and t h e t e r m s of t r a d e has t h e f o r m

where cr=l/a.
Case 2:

As noted earlier, t h i s function i s symmetric in k.
preference f o r home goods (w>l).

c=0.05, w=2, and 7=2.

To make t h i s concrete, l e t

With a=5, t h e standard deviation of t h e logarithm of

t h e t e r m s of t r a d e i s 0.497, slightly smaller than in t h e case of identical
preferences.

There

is

a

critical

value

cr*=O.885<1 of

the

elasticity

of

substitution such t h a t f o r cr>cr*, t h e t r a d e balance and t h e t e r m s of t r a d e a r e
positively

correlated,

and

cross-correlation function i s

which remains symmetric.

f o r crccr* they

a r e negatively

correlated.

The

clevelandfed.org/research/workpaper/index.cfm

5

T h e Marshall-Lerner Condition a n d t h e Harberger-Laursen-Metzler E f f e c t
The theory of

data

t h e l a s t two sections

a r e relatively

straightforward.

and i t s relation t o time series

We have

found,

however,

that

this

theory gives u s a much different understanding of t h e relation between t r a d e
and

relative

prices

Marshall-Lerner

than

that

condition

Harberger-Laursen-Metzler

underlying

or

the

effect.

either

1980s

the

widely

cited

on

the

literature

In this section, we contrast our work with

these other approaches.
The elasticity condition of

Proposition 1 i s an example of

a common

result in price theory, t h a t t h e sign of something depends on whether utility
i s more o r less concave than t h e log (cr=l).
surprising about it.
difference between

In t h a t sense, t h e r e i s nothing

What we find interesting in t h e present setting i s t h e
this

condition

and t h e Marshall-Lerner

condition,

often

cited as t h e determining f a c t o r in t h e sign of t h e relation between t h e t r a d e
balance

and

the

terms

of

trade.

The Marshall-Lerner

condition

is

the

centerpiece of textbook treatments of t h i s issue; among many other examples,
see Dornbusch

(1980, p.

591,

Ethier

(1988, pp.

402-71,

and Krugman

and

Obstfeld (1991, p. 423).
The Marshall-Lerner condition applies t o a s t a t i c economy, but we can
review i t s logic in a one-period
treatment follows Kemp (1987).

version of

our two-country

world.

Our

We start by deriving conditions on s t a t i c

import demand functions t h a t allow us t o express t h e balance of t r a d e as a n
increasing

function

of

the

terms

of

trade.

Among

the

conditions

for

equilibrium in t h e s t a t i c economy a r e t h e resource constraint f o r t h e home
good,

a l + a 2 = yl,
and t h e f i r s t agent's budget constraint,

clevelandfed.org/research/workpaper/index.cfm

These conditions together imply balanced trade:

Utility

maximization

by

both

agents,

subject

to

their

respective

budget

constraints, r e s u l t s in import demand functions, say a2(p) and bl(p).

These

functions define net exports as a function of t h e t e r m s of trade:

This function i s increasing in p if

+

&

&*

> 1,

where
=

c

-(abl/ap)[p/bl)

and
=

e*
a r e the

domestic and

foreign

(aa2/ap)(p/a2)

import

elasticities.

The

inequality

is the

well-known Marshall-Lerner condition.
We now apply t h i s analysis t o our economy.

The relevant import demand

functions a r e
bl(p)

where, as before, cr=l/a
domestic goods.

=

yl/(p+pD)

i s t h e elasticity of substitution between foreign and

The import elasticities a r e therefore
E:

=

cr-1
(l+crp )/(p+pC),

clevelandfed.org/research/workpaper/index.cfm

Adding these two expressions, we find t h a t f o r all positive p and cr,
E:

In other words,

+

t h e Marshall-Lerner

economy, regardless of

condition i s always satisfied

t h e value of

foreign and domestic goods.

when

consumers

t h e elasticity of

in this

substitution between

This example illustrates a more general result,
The Marshall-Lerner

cited by Ethier (1988, section A.3):
satisfied

> 1.

E*

in

the

two

countries

condition is always

have

identical

no

connection

homothetic

preferences.
Clearly,

the

Marshall-Lerner

elasticity condition of

condition

has

Proposition 1 and therefore

with

the

has no bearing on the

correlation between t h e t r a d e balance and the terms of t r a d e f o r time series
d a t a generated by economies like ours.

The difference in results stems, we

think, from t h e difference between dynamic modeling and t h e s t a t i c analysis
t h a t underlies the Marshall-Lerner

condition.

Despite t h e intuitive appeal

of t h e l a t t e r , we find t h a t when the dynamics a r e worked out explicitly, we
get a different interpretation of this property of the data.
The theoretical

s t a t e of

t h e art regarding

t h e relation

between

the

t r a d e balance and t h e t e r m s of trade, however, i s not t h e Marshall-Lerner
condition

but

the

1980s

revival

of

the

Harberger-Laursen-Metzler

initiated by Obstfeld (1982) and Svensson and Razin (1983).

effect

These papers,

and others t h a t followed, start with the central insight of the absorption
approach:

that

trade

imbalances

reflect

differences

between

investment.

The theoretical economies of these two papers a r e deterministic

but share with ours t h e f e a t u r e t h a t dynamics a r e explicit.

saving and

They come,

however, t o much different conclusions regarding t h e f a c t o r s t h a t lead t o a
positive association between t h e t r a d e balance and t h e t e r m s of trade.

These

papers suggest t h a t two f a c t o r s a r e critical in determining t h e pattern of

clevelandfed.org/research/workpaper/index.cfm

comovements: the persistence of the shock and the form of dependence of the
discount factor, o r r a t e of time preference,

on future utility.

Transitory

shocks typically lead, in their analysis, t o movements in the terms of trade
and the trade balance of

opposite sign.

We find,

in contrast,

that

the

relation between the trade balance and the terms of trade is independent of
the dynamics of prices.
The aforementioned papers also find that the effect of permanent shocks
depends on the behavior of the discount factor.
p.

100) put

it:

"A permanent

A s Svensson and Razin (1983,

terms-of-trade

deterioration

...

causes

a

deterioration or improvement in the real trade balance, depending on whether

...
the

the r a t e
level

of

of

time preference decreases o r

welfare."

Obstfeld

increases,

(1982) assumes

that

respectively,
the

rate

of

with
time

preference is increasing in utility and therefore predicts a decline in the
trade balance.
production

must

In his words (1982, p.
experience

a

fall

in

2511, "...an
aggregate

economy specialized in

spending

and

a

current

[account] surplus a s a result of an unanticipated, permanent worsening in i t s
terms of trade."

In both papers there is no effect of a permanent change in

price on the t r a d e balance if the r a t e of time preference is constant.

In

our economies, the r a t e of time preference is constant, fixed by the discount
factor

p.

The conclusion should then be t h a t permanent movements in the

terms of trade have no effect on the trade balance.

We find, instead, t h a t

the relation between the trade balance and the terms of trade is determined
by the elasticity of substitution, regardless of the persistence of shocks.
As

in

our

analysis

of

the

between our approach and that of
stems, in part,

Marshall-Lerner

the

difference

the Harberger-Laursen-Metzler

literature

from our definition of

the

condition,

issue.

In our

analysis,

the

relation between the trade balance and the terms of trade pertains t o the
correlation between these two variables f o r a single time series realization,

clevelandfed.org/research/workpaper/index.cfm

like t h e q u a r t e r l y series f o r
States

described

in

table

Japan,

4.1.

the

United

This

Kingdom,

corresponds,

in

and t h e
our

United

theoretical

economies, t o t h e correlation between t h e t w o variables along a n equilibrium
path.

In t h e analysis of

however,

the

Obstfeld (1982) and Svensson and Razin

Harberger-Laursen-Metzler

effect

pertains

between t w o different deterministic equilibria:

to

a

(19831,

comparison

one in which t h e t e r m s of

t r a d e i s high, and one in which i t i s low.

Apparently these t w o thought

experiments emphasize much different f e a t u r e s of t h e theory.

We would a r g u e

t h a t our thought experiment i s closer t o what we have in mind when we compare
theory and data.

A closer look also suggests, as brought out in Backus

(1992) and Stockman and Svensson (19871, t h a t t h e theory requires explicit
treatment

of

the

stochastic

structure

of

the

economy,

something

that

deterministic analysis obviously cannot provide.
One way in which these t w o points of view might be reconciled is t o
consider economies in which agents have more limited ability t o hedge risk
than they do in t h e complete market economies of sections 3 and 4.

e f f e c t , income e f f e c t s play a

1980s analysis of t h e Harberger-Laursen-Metzler
central role.

In t h e

In our economies, however, t h e r e a r e no income e f f e c t s along

a n equilibrium path.
budget constraint.

With complete markets, each agent has a single, date-0
As a result, each has a state-invariant

marginal utility

of income, reflected in t h e constant welfare weights of our optimum problem.
Backus (19921, Kehoe and Richardson (19851, and Mendoza (1992) suggest t h a t
some of t h e flavor of t h e Harberger-Laursen-Metzler

literature may c a r r y over

t o dynamic stochastic settings with some types of market incompleteness.
In short, we find t h a t explicit dynamic stochastic analysis of t r a d e and
relative prices
their

leads t o much

comovements.

Even

different views
the

role

of

of

that

Marshall-Lerner condition, may need t o be reconsidered.

t h e f a c t o r s determining
textbook

standard,

the

clevelandfed.org/research/workpaper/index.cfm

Government Spending

6

The theory t h u s f a r h a s focused on fluctuations in t r a d e and prices
arising f r o m movements in endowments.

Here we consider a n extension t o t h e

exchange economy of section 3 in which we have, in addition, exogenous shocks
t o government
(1992),

Buiter

spending.
(19891,

Related
Hodrick

Reynolds (1991), and Yi (1991).

analyses have been

(19881,

Macklem

provided

(19901,

by

Baxter

Obstfeld

(1989),

We f i n d t h i s extension both interesting in

i t s own right and a useful s t e p toward introducing a wide range of impulses
into dynamic general equilibrium models of trade:

shocks, f o r example, t o

t a x e s , t a r i f f s , and possibly even monetary policies.

To keep t h e analysis

simple, we r e s t r i c t ourselves t o t h e case of symmetric preferences (w=l

in

t h e Armington aggregator GI.
In t h i s new economy, t h e government i s a n additional consumer of goods.
Let us s a y t h a t in s t a t e zt t h e government of country i consumes t h e quantity

t
g.(z ) of i t s home good.

This spending i s financed with lump-sum t a x e s , say

1

t

ri(z

).

An equilibrium then consists of quantities (a and b i ) , prices (qi),
i

a n d government policies ( g . , ~ . ) such t h a t
1

prices

and

budget

1

constraints,

( i ) agents maximize utility given

(ii) quantities

satisfy

the

resource

constraints,

a n d (iii) policies satisfy governments' budget constraints.
With

this

structure,

the

endowments" yi-gi, r a t h e r than y
section 3 with little change.

economy
i'

is

equivalent

to

one

with

"net

and we can apply most of t h e r e s u l t s of

The equilibrium allocation includes

clevelandfed.org/research/workpaper/index.cfm

for

i=1,2,

with consumption

w e l f a r e weights A..

1

shares s

i

x!/'1 /z.x!/'J

=

J

f o r some choice of

The equilibrium t e r m s of t r a d e i s

The variability of t h e t e r m s of t r a d e is governed, then, by t h e variability
of

t h e net endowment r a t i o and t h e elasticity of

practice,

t h e addition of

substitution, cr=l/a.

In

government purchases has l i t t l e influence on t h e

variance of p, since g is only a f r a c t i o n of output and i s generally less
variable.

The same reasoning applies t o persistence:

purchases of

Introducing government

goods and services does l i t t l e t o change our prediction t h a t

relative prices retain t h e persistence of output ratios.
The most interesting consequences of government purchases concern trade.
If w.=y.-g.
1

1

1

i s t h e endowment net of government purchases, net exports in

country 1 a r e

t
nxl(z 1 =

t
(1-sl)wl(z 1

-

t
t -a
t
[w2(z )/wl(z 11 slw2(z

The r a t i o of net exports t o output i s

t
t
t
t 1-a
t
t
nxl(z l/yl(z 1 = ((1-sll - sl[w2(z )/wl(z 11 } wl(z )/yl(z 1.
In our earlier analysis, g

1

w a s z e r o and t h e last t e r m was, therefore, one.

As a result, t h e e f f e c t of t h e endowment r a t i o on t h e t r a d e balance, and t h e
and t h e t e r m s of
association between movements in t h e t r a d e balance, nx /y
1 1'
t r a d e , p, depended only on t h e value of cr=l/a.
positive; f o r cr<l t h e reverse.
of t h e net endowment, w

1'

For cr<l t h e association was

Here we find a n additional f a c t o r , t h e r a t i o

t o t o t a l output, y

1'

clevelandfed.org/research/workpaper/index.cfm

We can g e t some idea of t h e contributions of output and government
spending shocks on t r a d e and price fluctuations by considering special cases.
Consider, f i r s t , t h e case in which g

1

i s proportional t o y

1'

Then wl/yl

is

constant, and t h e relation between t h e t r a d e balance and t h e t e r m s of t r a d e
i s determined by cr, as i t w a s in Proposition 1.

With a>l ( o r u<l), t h e t r a d e

balance and t h e t e r m s of t r a d e a r e positively related along a n equilibrium
path; with cr<l, they a r e negatively related.
y. a r e constant and g
1

1

i s t h e only shock.

Alternatively, suppose outputs
Then t h e t r a d e balance and the

t e r m s of t r a d e a r e positively associated, regardless of t h e value of cr.

This

example i s like many others in economics in which t h e comovement between t w o
endogenous variables depends on t h e source of t h e i r fluctuations.
This analysis suggests a

second

look at t r a d e and price

special attention paid t o government purchases.
t h e r e h a s been l i t t l e regularity
of

government

purchases

a c r o s s countries

relative

to

that

correlation between these two variables.

of

data,

with

As we see in table 4.2,
in

either t h e

real

output,

variability
or

in

the

The same statement applies t o t h e

correlations of government purchases with t h e t r a d e balance and t h e t e r m s of
trade.

That i s not t o say t h a t government purchases have not played a role

in t r a d e and price behavior, but t h a t t h i s role i s not simple enough t o show
u p in summary s t a t i s t i c s of t h i s form.

Froot and Rogoff

(1991) document

somewhat stronger indications of a relation between government spending and
r e a l exchange r a t e s using different methods.

7

T r a d e a n d C a p i t a l Formation
In t h e exchange economies of sections 3 and 4, we compared properties of

t h e d a t a with analogous properties of
theoretical economies.
closer look.

t r a d e and relative prices in simple

This analysis brought up two questions t h a t deserve a

We found, f o r one thing, t h a t t h e variability of t h e t e r m s of

clevelandfed.org/research/workpaper/index.cfm

t r a d e i s governed by the variability of the output ratio and the elasticity
of

substitution between foreign and domestic goods.

By choosing a small

enough elasticity, the theory can generate literally any amount of
price variability.
in

the

theory

elasticity.
not,

for

relative

The question, in this case, i s whether price variability
and

the

data

are

close

for

reasonable

values

of

this

In another respect, we found t h a t the exchange economy could
any

choice

of

parameter

values,

mimic

the

data:

cross-

the

correlation function f o r the t r a d e balance and the terms of trade.

In the

d a t a this function i s generally asymmetric, a feature we document in figure
4.1 and label the S-curve.

In the exchange economy, however, the function i s

symmetric by construction,

since both the t r a d e balance and the terms of

t r a d e a r e functions of the same s t a t e variable.

The question here i s whether

this property changes when we introduce physical capital formation.
The introduction of capital formation brings us closer t o the theme of
the absorption approach t o the balance of payments:

t h a t fluctuations in

t r a d e reflect differences between saving and investment.

A s a matter of pure

accounting, this connection i s undeniable, but i t also shifts one's
away from within-period
save and invest.

relative prices t o the intertemporal

attention

decisions t o

Thus, Sachs (1981) argues that trade deficits often reflect

investment booms and Stockman and Svensson (19871 tie both t r a d e and relative
prices t o fluctuations in, among other things, fixed capital formation.

We

continue this tradition by introducing capital formation t o an economy t h a t
i s otherwise like our earlier ones.
Kehoe, and Kydland (1992b).

The structure i s adapted from Backus,

The emphasis, a s in earlier sections, i s on the

dynamics of the t r a d e balance and the terms of trade.
The theoretical

economy has the following elements.

before, two countries that specialize in different goods.

There are,

as

Preferences of the

representative consumer in each country i a r e characterized by a n expected

clevelandfed.org/research/workpaper/index.cfm

utility function of t h e f o r m

where c

it

and n

it

a r e consumption and hours worked in country i, U(c,l-n) =

[cp(l-n)'-'1'-~/(1-7),

and 720.

The primary difference in preferences f r o m

section 3 i s t h e appearance of

t h e economy of

leisure

in agents'

utility

functions.
Goods in t h e t w o countries, labeled
country

2,

are

produced

using

a

f o r country 1 and

k,

and

capital,

labor,

n,

b

with
8 1-8

homogeneous production functions of t h e same form, F(k,n) = k n

for
linear

.

This

gives r i s e t o t h e date-t resource constraints,

in countries 1 and 2, respectively.

The quantity y

i, measured in units of t h e local good, and a
t w o goods in country i.
exchange

setting

of

it

it

denotes GDP in country

and bit

denote uses of t h e

If k and n a r e constant, t h i s reduces t o t h e pure

section

3,

with

proportionate output fluctuations.

productivity

shocks

giving

The vector zt = (zlt,z2t)

rise

to

i s a stochastic

shock t o productivity whose properties will be described shortly.
Consumption,

investment, and government spending in each country a r e

composites of t h e foreign and domestic goods, with

1-a 1-all/(l-a)
where, as before, G(a,b) = [wa +b
both

positive,

and

the

domestic goods i s cr=l/a.

elasticity

of

.

The parameters a and w a r e

substitution

between

foreign

and

As noted earlier, t h i s s t r u c t u r e i s widely used in

clevelandfed.org/research/workpaper/index.cfm

s t a t i c general equilibrium models of trade.

Capital stocks evolve according

to

where 6 i s t h e depreciation rate.
the

exchange

economy

of

Two differences between t h i s economy and

sections

3-5

are

the

introduction

of

capital

formation and t h e assumption here t h a t government spending may have some
foreign content.
Finally, t h e underlying shocks t o our economy a r e independent bivariate
autoregressions.

where

E

Z

The technology shocks follow

i s distributed normally and independently over time with variance

The correlation between t h e technology shocks, z

vz'

by t h e off-diagonal elements of A and VZ.

1

and z
i s determined
2'

Similarly, shocks t o government

spending a r e governed by

where

g

t

=

( g , g 1 and
It 2t

cg i s distributed

normally

with

variance

V

g'

Technology shocks, z, and government spending shocks, g, a r e independent.
With these elements, and t h e parameter values listed in table 4.3, we
can approach t h e behavior of t h e t e r m s of trade.

The critical parameters,

f o r our purposes, a r e t h e elasticity of substitution, cr, which we s e t equal
t o 1.5, and t h e steady-state r a t i o of imports t o GDP, which w e s e t equal t o
0.15 by choosing w appropriately.

In t h i s benchmark version of t h e economy,

foreign and domestic goods a r e b e t t e r substitutes t h a n they would be with
Cobb-Douglas preferences (cr=l) and imports a r e , on average, 85 percent of
GDP.

The choice of elasticity i s in t h e range of estimates f r o m a large

number of studies, a s documented by Whalley (1985, ch. 4).

Estimates of t h e

clevelandfed.org/research/workpaper/index.cfm

elasticity a r e generally close t o one, and often slightly larger.

The import

s h a r e i s slightly l a r g e r than we s e e in t h e United S t a t e s , Japan, o r a n
aggregate of European countries (with intra-European t r a d e netted out), but
smaller than we s e e f o r most countries individually.
A number

of

properties

of

t h e theoretical

parameter settings a r e reported in table 4.4.
in t h e t e r m s of trade.

economy

with

alternative

Consider, f i r s t , fluctuations

The standard deviation of t h e t e r m s of t r a d e with our

benchmark parameter values i s 0.48 percent, which i s a f a c t o r of s i x less
than we see f o r t h e United S t a t e s in table 4.1.

With smaller values of cr,

t h e theoretical economy generates g r e a t e r variability of t h e t e r m s of trade.
A s illustrated in f i g u r e 4.2, t h e standard deviation of p g e t s larger as we

decrease c , and f o r cr less than 0.03 t h e standard deviation exceeds 2.

Thus,

i t appears t h a t while t h e theory can produce as much variability in t h e t e r m s
of t r a d e as we s e e in t h e d a t a , i t requires a n elasticity of

substitution

much smaller t h a n most existing estimates.
The value of cr required t o match t h e variability of t h e t e r m s of t r a d e
in US d a t a i s substantially smaller in t h i s model (less than 0.03) than in
our calculation in section 3 f o r t h e United S t a t e s and Japan ( f o r which we
estimated t h a t w=0.73 would be sufficient).
of t h i s difference.

Three f a c t o r s account f o r most

The f i r s t i s t h a t t h e theoretical economy has, in t h e

benchmark case, about 25 percent less variability in t h e output r a t i o t h a n we
calculated f o r Japan and t h e United States.

Modifications of t h e theory t h a t

bring t h e magnitude of business cycles closer t o t h e d a t a will also bring t h e
theory

and

data

closer

together

second f a c t o r i s capital formation.
by

setting

8=0

in

the

with

respect

price

variability.

The

If we eliminate capital (which w e can do

production

function),

considerably g r e a t e r price variability, despite
of outputs.

to

the

economy

less variability

The final f a c t o r i s t h e import share.

generates

in t h e r a t i o

If t h e import s h a r e i s

clevelandfed.org/research/workpaper/index.cfm

raised

from 0.15 t o

value of cr.

0.25,

the variability

increases substantially a t

every

For cr=1.5, the benchmark value, the standard deviation of the

relative price rises from 0.48 t o 0.58.
second

A

property

of

the

model

is

the

between net exports and the terms of trade.

contemporaneous

correlation

In the data, this correlation

has been positive f o r the United States and negative f o r Japan and the United
Kingdom

(see

benchmark
expect

table

4.1).

In

the

theoretical

economy

we

find,

Propositions

elasticity

of

increases

with

1 and

substitution.
cr,

and

is

We

2,

this

see

in

positive

for

correlation
figure

4.3

elasticities

is

the

A s we might

parameter values, that the correlation is -0.41.

from

for

sensitive

that

the

greater

the

correlation

than

This feature, too, is strongly influenced by capital formation.

to

cr*=2.76.

In the model

without capital (8=0), the economy is much like that described in Proposition
2, with a critical elasticity cr*=0.94.

For cr>cr*, the trade balance and the

terms of trade a r e positively correlated; f o r crccr*, the reverse.
A third property of interest is the impact of government spending on the

correlation between the trade balance and the terms of trade.

We see in

table

correlation

4.4

that

with

only

shocks t o

government

spending,

the

between net exports and the terms of trade shifts from negative t o positive.
This

mirrors

productivity,

a
z,

similar
and

result

government

in

section

spending,

6.
g,

With
we

find

shocks
that

to

the

both

former

dominate, in the sense that the economy's properties a r e similar t o those
with shocks t o productivity alone.
Finally,

we

look

at

the

exports and the terms of trade.

complete

cross-correlation

function

for

net

A s pictured in figure 4.4, this correlation

has the same asymmetric shape we documented f o r the data in figure 4.1.

Some

intuition f o r this behavior is provided by figure 4.5, in which we graph the
dynamic responses t o a one-standard-deviation

shock t o domestic productivity.

clevelandfed.org/research/workpaper/index.cfm

Following t h i s shock,
increase.

output and t h e relative price of

foreign goods both

Consumption also rises, but by less than output.

Investment grows

initially by much more than consumption, as resources a r e t r a n s f e r r e d t o t h e
home

country

to

exploit

its expected f u t u r e productivity

capital accumulates, t h i s resource t r a n s f e r diminishes.

advantage.

As

The t r a d e balance,

which i s t h e difference, at market prices, between output and t h e sum of
consumption and investment,
by surplus.

exhibits an initial period of

deficit, followed

These dynamic responses give r i s e t o t h e asymmetric cross-

correlation function of figure 4.4.
In short,

much of

t h e intuition f o r t h i s dynamic general equilibrium

t r a d e model i s available f r o m t h e exchange economy of sections 3-5.

What t h e

exchange economy misses completely a r e the dynamics of t h e relation between
t h e t r a d e balance and t h e t e r m s of trade:

t h e asymmetric cross-correlation

function t h a t we documented in t h e d a t a and
cross-correlation

labeled t h e S-curve.

function between these two variables

exchange economy f o r all parameter values.
t h a t t h e dynamics of

The

is symmetric in the

In t h i s section, we have seen

capital formation provide

a plausible basis f o r a n

asymmetric pattern.

8

F i n a l Thoughts
We have argued t h a t a dynamic general equilibrium approach t o aggregate

t r a d e theory provides both a new level of understanding of t h e interrelations
between t r a d e and price movements and a framework in which these relations
can be quantified.

With regard t o t h e former, we have seen t h a t t h e relation

between t r a d e and price variables is much different f r o m t h a t suggested by
t h e Marshall-Lerner

condition cited in most textbooks.

With r e g a r d t o t h e

l a t t e r , we suggest t h a t t h e dynamic relation between t r a d e and t h e relative
price of foreign goods can be understood as a consequence of t h e dynamics of

clevelandfed.org/research/workpaper/index.cfm

capital formation.

Thus, the dynamics of

trade variables a r e inseparable

from the dynamics of the r e s t of the economy.
Future work will undoubtedly focus, however, not on these contributions,
but on dimensions in which the theory, in i t s current incarnation, provides a
relatively poor approximation t o the dynamics of actual economies.
obvious example i s the variability of the terms of trade.

The most

In the economy of

section 7, and in Stockman and Tesar (1991) a s well, the standard deviation
of the terms of t r a d e is substantially smaller than we estimate in the data.
This discrepancy between theory and data helps t o motivate theories in which
monetary

policy

influences

relative

prices

(Grilli

and

Roubini

1992,

Schlagenhauf and Wrase 19921 and in which international market segmentation,
possibly in conjunction with imperfect competition, also plays a part (Dumas
1992, Giovannini 1988, Lapham 1990).

Ongoing research will likely tell us

how important each of these features is, and how they modify the lessons of
the theory outlined above.

clevelandfed.org/research/workpaper/index.cfm

REFERENCES
Alterman, W. 1991. "Price trends in US trade:

New data, new insights." In

P. Hooper and J.D. Richardson (eds. 1, International Economic

Transactions: Issues in Measurement and Empirical Research. Chicago:
University of Chicago Press.
Armington, P. 1969. "A theory of demand f o r products distinguished by place
of production." IMF S t a f f Papers 27, 488-526.
Backus, D. 1992. "Interpreting comovements in t h e t r a d e balance and t h e
t e r m s of trade." Journal o f International Economics, forthcoming.
Backus, D., Kehoe, P., and Kydland, F. 1992a. "International r e a l
business cycles." Journal o f Political Economy 100 (August), 745-775.
Backus, D., Kehoe, P., and Kydland, F. 1992b. "Dynamics of t h e t r a d e
balance and t h e t e r m s of trade: The S-curve." Federal Reserve Bank of
Cleveland, Working Paper 9211, October.
Baxter, M.

1992. "Fiscal policy, specialization, and t r a d e in t h e two-sector

model: The r e t u r n of Ricardo?" Journal o f Political Economy 100
(August), 713-744.
Blackburn, K., and Ravn, M. 1991. "Contemporary macroeconomic fluctuations:
An international perspective. " Unpublished manuscript, January.
Buiter, W. 1989. Budgetary Policy, International and Intertemporal Trade in

the Global Economy. Amsterdam: North Holland.
Cole, H., and Obstfeld, M. 1991. "Commodity t r a d e and international
risk-sharing." Journal o f Monetary Economics 28 (August), 3-24.
Dornbusch, R. 1980. Open Economy Macroeconomics. New York: Basic Books.
Dumas, B. 1992. "Dynamic equilibrium and the r e a l exchange r a t e in a
spatially separated world. " Review o f Financia l Studies 5, 153-180.
Ethier, W. J. 1988. Modern International Economics, Second Edition. New York:
Norton.

clevelandfed.org/research/workpaper/index.cfm

Froot, K., and Rogoff, K. 1991. "Government spending and the real exchange
r a t e in the Bretton Woods era." Unpublished manuscript.
Giovannini, A. 1988. "Exchange r a t e s and traded goods prices." Journal of

International Economics 24, 45-68.
Graboyes, R. 1991. "International trade and payments data." Federal Reserve
Bank of Richmond, Quarterly Review 77 (September/October), 20-31.
Grilli, V.,

and Roubini, N. 1992. "Liquidity and exchange rates. "

Journal of International Economics 3 2 (May), 339-352.
Harberger, A. 1950. "Currency depreciation, income, and the balance of
trade." Journal of Political Economy 58, 47-60.
Hodrick, R. 1988. "US international capital flows: perspectives from
rational maximizing models. " Carnegie-Rochester Conference Series on

Public Policy 3 0 (Spring), 231-288.
Kehoe, P., and Richardson, P. 1985. "Dynamics of the current account:
Theoretical and empirical analysis." Federal Reserve Bank of
Minneapolis, Working Paper.
Kemp, M. 1987. "Marshall-Lerner condition." The New Palgrave: A Dictionary

of Economics. London: Macmillan.
Krugman, P., and Obstfeld, M. 1991. International Economics: Theory and

Policy, Second Edition. New York:

HarperCollins.

Lapham, B. 1990. "A dynamic, general equilibrium analysis of deviations from
the laws of one price." Unpublished manuscript, Queen's University,
September.
Laursen, S., and Metzler, L. 1950. "Flexible exchange r a t e s and the theory of
employment. " Review o f Economics and Statistics 32, 281-299.
Lucas, R. 1984. "Money in a theory of finance. " Carnegie-Rochester Conference

Series on Public Policy 21, 9-45.
Macklem, R.T. 1990. "Terms-of-trade

disturbances and fiscal policy in a small

clevelandfed.org/research/workpaper/index.cfm

open economy." Bank of Canada, Working Paper 90-7, December.
Mendoza, E. 1992. "The terms of t r a d e and economic fluctuations." Unpublished
manuscript, International Monetary Fund, February.
Mussa, M. 1986. "Nominal exchange r a t e regimes and the behavior of real
exchange rates." In K. Brunner and A. Meltzer (eds.), Real Business

Cycles, Real Exchange Rates, and Actual Policies. Carnegie-Rochester
Conference Series.
Obstfeld, M. 1982. "Aggregate spending and the terms of trade: Is there a
Laursen-Metzler effect?" Quarterly Journal o f Economics 97 (May),
251-270.
Obstfeld, M. 1989. "Fiscal deficits and relative prices in a growing
economy." Journal o f Monetary Economics 23 (May), 461-484.
Reynolds, P. 1991. "Capital formation, government spending and international
economic fluctuations. " Unpublished manuscript, Northwestern

University,

January.
Sachs, J. 1981. "The current account and macroeconomic adjustment in the
1970s. " Brookings Papers on Economic Activity (I), 201-268.
Schlagenhauf, D., and Wrase, J. 1992. "A monetary, open-economy model with
capital mobility." Unpublished manuscript, Arizona S t a t e University.
Stockman, A., and Svensson, L. E. 0. 1987. "Capital flows, investment, and
exchange rates," Journal o f Monetary Economics 19, 171-201.
Stockman, A., and Tesar, L. 1991. "Tastes and technology in a two-country
model of the business cycle: explaining international comovements."
Federal Reserve Bank of Cleveland, Working Paper 9019, April.
Svensson, L., and Razin, A. 1983. "The terms of trade and the current
account: The Harberger-Laursen-Metzler effect." Journal o f Political

Economy 91 (February), 97-125.

clevelandfed.org/research/workpaper/index.cfm

Whalley, J. 1985. Trade Liberalization Among Major Trading Areas. Cambridge,
MA: MIT Press.

Yi, K.-M. 1991. "Can government purchases explain recent US net e x p o r t
deficits?" Unpublished manuscript, presented at t h e NBER Universities
Conference, May.

clevelandfed.org/research/workpaper/index.cfm

APPENDIX:

Proof o f Proposition 2

The algebra behind Proposition 2 i s s t r a i g h t f o r w a r d but f a i r l y tedious.
We start by reducing t h e economy t o t w o equations in t w o unknowns.
the

consumption

shares

of

the

first

agent,

sa=a /y
1 1 1

unknowns

are

b
s =b /y
1 1 2'

The f i r s t - o r d e r conditions and resource constraints then imply

The
and

and

b a
where m=b /a -xs /s >O and v=2/a>0.
With these substitutions, t h e t w o
1 1 - 1 1
a
equations determine s and sb as functions of t h e endowment r a t i o x=y /y
1
1
2 1'
Note t h a t if either w = l

o r a=;r, t h e r i g h t side of

(A21 i s one and sa i s
1

constant.
Preliminaries:

a
Thus, s and s:
1

(a1 If we differentiate t h e f i r s t equation we g e t

a r e positively related

and we can use t h i s relation

b
s u b s t i t u t e out any d s 's we get.
1
b a
( b ) Differentiate t h e r a t i o (s /s 1:
1 1
b a
d ( s /s 1
1 1

=

b
1

(S /S

a
b a v
a a
1 [(s1/S 1 10 -11 dsl/sl.
1

(c) Differentiate m:

dm/m

(dl Inequalities.

b a v
a a
= dx/x + I ( s l / s l l w -11 dsl/sl.

From (A11 and w>l:

b a v
( s l / s l ) w -1

=

a b
(sl-sll/(l-s:)

> 0.

to

clevelandfed.org/research/workpaper/index.cfm

We now prove t h e claims in t h e t e x t .

a
We show t h a t sl is increasing in x if 7>a, and decreasing if 7<a.

1.

We differentiate (A2) and find, a f t e r rearrangement:

If we substitute t h e expression f o r dm/m

[ ( c ) above1 we g e t a n equation of

the form

so that

a
sl i s increasing in x

if

B/A>O,

and decreasing otherwise.

The

coefficient of dx/x i s

Since w>l, B has t h e same sign as 7-a.

a a
The coefficient of d s /s i s
1 1

a
Clearly if 7<a, A i s positive and d s /dx i s negative.
1
A/7

=

1-a
l+v 1-a
2+v) 1-a
(w+m ) (l+w m
) + 8 (1-w
m
,

a b
where 8=(s -s )(7-a)/;r<l.
1 1
in t h i s case, too.
2.

If p a , then

Combining terms makes i t clear t h a t A i s positive

Thus, the sign of dsa/dx i s t h e same as t h e sign of 7-a.
1

An immediate corollary i s t h a t c /c i s increasing in x:
2 1

The f i r s t -

order conditions imply

The behavior of
c

2

/C

1'

sy with respect t o x implies t h a t t h e consumption ratio,

i s increasing in x , as claimed in t h e text.

3.

We now show t h a t b /a =m i s increasing in x.
1 1

From (A31 we have

clevelandfed.org/research/workpaper/index.cfm

From the definition of B,

Since A>O, m is increasing in x.
4.

We turn t o the dependence of the trade balance on x.

A s in the

text,

Differentiating, we find

which is positive if

From (A4) and (AS) we can show that this inequality holds f o r large enough a.

clevelandfed.org/research/workpaper/index.cfm

Table 4.1
Properties of the Trade Balance and the Terms of Trade
Standard
Dev. (%)
Country
Japan

United Kingdom

United States

Autocorrelation

CrossCorrelation

Period

P

nx

P

1955-89
1955-70
1971-89

5.97
2.17
7.76

.97
.98
.94

.87
.73
.87

nx
.77
.66
.83

1955-89
1955-70
1971-89

2.71
1.51
3.38

1.08
.78
1.21

.76
.38
.79

.66
.54
.65

- .54

1955-89
1955-70
1971-89

2.99
1.31
3.84

.45
.30
.55

.82
.65
.84

.80
.79
.80

.30
.28
.30

(P,nx>

(P,Y)

- .46

- .09

- .55
- .51

-. 15

-.60

.41

- .27
.20
.56
.10
- .09

.47
- .23

Variables are p, the terms of trade, logarithm; nx, the ratio of net exports to output; y, real output,
logarithm. Data are quarterly from the OECD's Quarterly National Accounts. Statistics refer to
Hodrick-Prescott filtered variables.
SOURCE: Authors' calculations.

clevelandfed.org/research/workpaper/index.cfm

Table 4.2
The Trade Balance, the Terms of Trade, and Government Purchases
Standard
Deviation
Country

Y

g

Australia

1.47

Austria

Cross-Correlations

@,nx>

(g,nx>

1.90

-.I1

-.I5

1.27

.45

- .25

Canada

1.49

1.16

-.06

France

.91

.66

- .50

Germany

1.47

1.22

-.09

Italy

1.70

.69

Japan

1.48

Switzerland

.I1
-.I5

(g,~) (g,~)

.15
.28
-.02

.17
-.23
-.22

-.45

.24

-.I1

-.I6

.23

-.66

.ll

-.42

1.54

-.51

.19

-.35

.02

1.94

1.01

-.61

-.I5

-.29

.28

United Kingdom

1.60

1.07

-.60

-.06

-.01

.06

United States

1.93

1.47

.31

.ll

-.28

.13

-.01

.12

The sample period is 1971:l to 1989:4. Variables are p, the terms of trade, logarithm; nx, the ratio of net exports to output; y, real output, logarithm; g, real
government purchases of goods and services, logarithm. Data are quarterly from the
OECDYsQuarterly National Accounts. Statistics refer to Hodrick-Prescott filtered
variables.
SOURCE: Authors' calculations.

clevelandfed.org/research/workpaper/index.cfm

Table 4.3
Benchmark Parameter Values

Preferences
Technology

8 = 0.36, 6 = 0.025, a = l l a = 1.5,

import share = 0.15
Forcing Processes

var ~f = var

E:

= 0.008522,

C O ~ T ( E=~0.258
,E~
gt = 0

SOURCE: Authors' calculations.

clevelandfed.org/research/workpaper/index.cfm

Table 4.4
Properties of Theoretical Economies with Capital Formation
Standard
Deviation (%)

Autocorrelation

Correlation

nx

Y

P

nx

Y

P

.30
(.02)

1.38
(. 18)

.48

.63
(. 10)

.83
(.05)

-.64

(.M)

.61
(.07)

Large Elasticity

.33
(.03)

1.41
(.18)

.35
(.05)

.63
(.07)

.64
(. 18)

Small Elasticity

.37
(.03)

1.33
(. 18)

.76
(.07)

.61
(.07)

Big Share

.63
(.04)

1.37
(. 18)

.58
(.08)

.59
(.07)

Small Share

.08
(.01)

1.38
(.18)

.43
(.06)

Two Shocks

.33
(.03)

1.33
(. 15)

Govt. Shocks

.16
(.03)

.17
(.02)

Economy
Benchmark

( W Y ) (WP)

@,P)

(.07)

-.41
(.08)

.49
(.14)

.88
(.03)

-.57
(.08)

-.05
(.09)

.43
(.14)

.63
(. 10)

.77
(.05)

-.66
(.07)

-.80
(.09)

.51
(.16)

.64
(. 10)

.83
(.04)

-.61
(.07)

-.41
(.07)

(. 13)

.62
(.07

.63
(. 10)

.81
(.05)

-.65
(.07)

-.41
(.08)

.48
(.14)

.57
(.07)

.62
(.08)

.65
(.08)

.78
(.06)

-.57
(.15)

-.05
(.17)

.39
(.17)

.30
(.05)

.67
(.ll)

.67
(.08)

.67
(. 11)

-.55
(.13)

1.00
(.00)

-.55
(.13)

.52

Variables are defined in Table 4.1. Statistics refer to Hodrick-Prescott filtered variables. Entries are averages
over 20 simulations of 100 quarters each; numbers in parentheses are standard deviations. Parameters as in
Table 4.3, except large elasticity, a = 2.5; small elasticity, a = 0.5; big share, import share = 0.25; small
share, import share = 0.05; two shocks, mean of g = diag(0.2,0.2), B = diag(0.95,0.95), and V, =
diag(0.0042,0.0042);government shocks, as in two shocks plus z, = 1, all t.
SOURCE: Authors' calc~.llations.

clevelandfed.org/research/workpaper/index.cfm

Fig. 4.1 S-CURVES IN THE DATA
JAPAN

0.75

ALL

U

-0.50 --

\

/ I ' \ \

-0.75

I

I

I

I
I

I

I

1

d-/ /

\

>

I
I

I

I

I

I

I

PRE-72
POST-72

/

I
I

I

I

I
1

1

1

--

,
,
,

I

I
I

I

I

1

UNITED KINGDOM

0.75 7

UNITED STATES

0.75 7

--

\

/
/

/
\

--0.75

!

\

/

ALL

/

PRE-72
POST-72

- - I _

I
I

-8

I

I

I

I

I

I

I

I

-6

-4

I
I

I
I

I

I

I

I

I

I

I

I

-2
0
2
Lag k of p behind nx

SOURCE: Authors' calculations.

I

I

I

I

4

I

I

I

I

6

---I
I

8

clevelandfed.org/research/workpaper/index.cfm

Fig. 4.2 VARIABILmY OF THE TERMS OF TRADE

Elasticity of Substitution, o
SOURCE: Authors' calculations.

clevelandfed.org/research/workpaper/index.cfm

Fig. 4.3 CORRELATION OF THE TRADE BALANCE
AND TERMS OF TRADE

0.8 -

0.6 -0.4 --

3

2

4

5

Elasticity of Substitution, o
SOURCE: Authors' calculations.

6

clevelandfed.org/research/workpaper/index.cfm

Fig. 4.4 S-CURVE FOR THE BENCHMARK ECONOMY

Lag k of p over nx
SOURCE: Authors' calculations.

clevelandfed.org/research/workpaper/index.cfm

Fig. 4.5 DYNAMIC RESPONSES TO DOMESTIC
PRODUCTIVITY SHOCK

...
..
1.00 --

120

8

*,

s

C)

8y 0.80 --

OUTPUT

..
-..

3

X

3m 0.60--

---.- - - - - -

- - - _- - - - - - _- - - - - - - - - _ _ PRODUCI'M~

b

o

u

SHOCK

0.40 --

8

- - 2 -

020--

/

I

I
-

-

TERMS OF TRADE

4

4
-

4
-

4
-

4
-

4
4

4

- 2 .

- 0 2 0 l ~ I 1 1 I I I 1 I I I I I I I I 1 I I I I I I I
0
3
6
9
12
15
18
21

Time in Quarters
SOURCE: Authors' calculatio~is.