SlideShare a Scribd company logo
International Trade Theory
Biswajit Nag
TWO BASIC QUESTIONS IN
INTERNATIONAL TRADE:
1) WHAT DETERMINES INTERNATIONAL TRADE?
2) WHY COUNTRIES WOULD GAIN FROM TRADE?
Historical Development of Trade Theory
 Mercantilism
– positive trade balance
 Absolute advantage (Adam Smith)
– Countries benefit from exporting what they
make cheaper than anyone else
 Comparative advantage (David Ricardo)
– Nations can gain from specialization, even
if they lack an absolute advantage
Foundations of trade theory
Absolute Cost Advantage Theory
(Adam Smith)
Assumptions: 1) Labour Theory of Value
2) Free Trade
Country 1 Unit of A 1 Unit of B
I 10 20
II 20 10
Labour Cost of Production (in Hours)
The Difference on absolute cost of producing the
commodities between the two countries in isolation will
serve a useful basis for opening up of mutually gainful
international trade between two countries.
David Ricardo
Theory of Comparative Cost Advantage
Basis of International Trade is the comparative cost
differences between two countries. According to this
theory, Adam Smith’s Absolute Cost Advantage
Theory is not quite unambiguous proposition. Cases
may arise where any one country may enjoy absolute
advantage over other country in both the goods.
Under such circumstances still trade may occur
given that there exists comparative cost difference.
Example
Labour Cost (in Hours) for 1 unit of production
Country Wine Cloth
Portugal 80 90
England 120 100
Portugal has absolute advantage in both cloth
and wine over England. According to Ricardo
trade is still worthwhile due to comparative cost
difference. In Portugal, 1 unit of wine= 8/9 units
of cloth, where as it is 12/10 in England. So,
opportunity cost of production of 1 unit of wine
in Portugal is 8/9 units of cloth but in England it
is 12/10. So, Portugal enjoys comparative cost
advantage in production of wine.
Country Wine Cloth
Portugal 80 90
England 120 100
Reference Table
Country Wine Cloth
Portugal 8/9 9/8
England 12/10 10/12
Opportunity Cost* for
*The opportunity cost for good X is the amount of other
goods which have to be given up in order to produce one
additional unit of good X.
Thus Portugal has lower opportunity cost of the two countries
in producing wine while England has lower opportunity cost in
producing cloth. So, Portugal has a comparative advantage in
production of wine and England has an advantage in production
of cloth.
So, in this case Comparative cost serve
as an useful basis for opening up of a
gainful international trade between
Countries. Each country seeks here to
specialise in production and export of
the commodity in which it has
comparative advantage and wants to
import the other commodity from its
trading partner.
Live Example
Suppose,
India 1US$= Rs. 50
Tanzania 1US$= Tnz
Shilling 1000
(Rates are assumed
for simplification of
calculation)
Water Beer Pw/Pb
India Rs. 10 Rs. 30 1/3
Tanzania Ts. 500 Ts. 700 5/7
In terms of absolute cost, both water and beer are cheaper in India
Suppose both the countries decide for a price ratio of ½, then India
will gain in selling water and Tanzania in Beer.
Explanation: Domestically in India a person has to sell 3 bottles of
water to get a bottle of beer but if he buys from Tanzania, he requires
to exchange only 2 bottles of water to get 1 bottle of beer. On the
other hand in Tanzania when a person sells a bottle of beer he/she
gets slightly more than a bottle of water, but if the beer bottle is sold
internationally to India, the gain is more as the person will get full 2
bottles of water in return.
Transformation schedules or Production Possibility
 Generalizes theory to include all factors, not
just labor
 Shows combinations of products that can be
made if all factors are used efficiently
 Slope, or marginal rate of transformation,
shows the opportunity cost of making more of
one good (how much of one good must be
given up to make more of another)
Comparative advantage
The opportunity cost version of Comparative
cost: The concept of Production Possibility
Curve (PPC)
Wheat
Cloth
The concept of Opp. Cost can
be described through PPC.
This shows alternative
combination of any two
products that can be
produced efficiently with
given resources and
technology. In virtue of full
employment and efficient use
of resources, it is true that
PPC will be downward
slopping. But it may either a
straight line or concave or
convex curve to the origin.
.
Slope of PPC measures marginal
opp. Cost of producing one
commodity in terms of others
Wheat
Cloth
Under condition of
constant cost in
production PPC becomes
a straight line.
Again if law of increasing
cost is operating then PPC
will be concave. This is so
because factors of
production may not be
adaptable completely to
the two alternative use.
In case of decreasing cost condition in
production, PPC will be convex to the
origin
Marginal Rate of Transformation
0
10
20
30
40
50
60
70
0 20 40 60 80 100 120 140
Autos
A
B
C
Slope = MRT = 0.5
Wheat
Wheat
Cloth
PPC and Price Line
Under constant cost condition PPC
coincides with the price line*
But this is not so in case of
varying cost condition because
in this case cost alone does not
determine the prices. We have
to consider the demand
conditions also. Given the
internal demand condition we
need to draw a separate price
line whose slope will represent
the ratio of exchange between
goods.
*The slope of the Price
line denotes the relative
price ratio of two
products.
Indifference curves
 Final pattern of trade depends not just
on supply, but also on demand - which
is determined by individual tastes
 Tastes can be shown graphically with
indifference curves, which show the
various combinations of two goods that
give a consumer the same total level of
satisfaction
Bringing demand into the model
A consumer’s indifference map
0
1
2
3
4
5
6
7
0 1 2 3 4 5 6 7 8 9
Autos
Bringing demand into the model
A
B
C
D
E
I
II
III
Wheat
Indifference curves (cont’d)
 “Higher” indifference curves (those
farther from the origin) represent greater
levels of satisfaction
 Individual preferences cannot really be
added up into a “community indifference
curve” but it is useful to imagine that
they can for the purposes of trade
theory
Bringing demand into the model
Indifference curves (cont’d)
 Indifference curves have a negative
slope
– Keeping satisfaction constant means giving
up some of one good for more of another
 Indifference curves are convex
– As the consumer gets more of one good,
she is less willing to give up what is left of
the other
– The rate of substituting one good for
another is shown by the slope of the curve,
the marginal rate of substitution
Bringing demand into the model
Equilibrium
Black Line: Price Ratio
Red Curve: PPC
Green Curves: Community Indifference
curve (CIC), denotes preference pattern of
the community
Equilibrium
A Community’s demand
pattern is described by its
CICs. Production of the
goods by PPC. Price ratio
by the price line.
Y
X
Equilibrium occurs at R which we call the point
of autarky or equilibrium in absence of
international trade. At this point. PPC becomes
tangent to the highest achievable CIC (and also
price line).
R

More Related Content

PPTX
International Trade - T.Y.B.Com Sem. VI.pptx
PPTX
Absolute and comparitive_advantage
PPTX
chapter 04.pptx
PPTX
Econ452 Learning Unit 02
PPTX
Econ452 Learning Unit 02 - 2020 fall
PPTX
Meeting 1 - Introduction to international economics (International Economics)
PPT
RicardoComparativeAdvantage2020F.ppt
PPTX
Comparative cost advanatge theory
International Trade - T.Y.B.Com Sem. VI.pptx
Absolute and comparitive_advantage
chapter 04.pptx
Econ452 Learning Unit 02
Econ452 Learning Unit 02 - 2020 fall
Meeting 1 - Introduction to international economics (International Economics)
RicardoComparativeAdvantage2020F.ppt
Comparative cost advanatge theory

Similar to Basics of International Trade.ppt (20)

DOCX
Economic conditions and international tradeMBA 681 Economi.docx
PPTX
CLASSICAL THEORY OF TRADE OR David RIcardo's theory of international trade.pptx
DOCX
Ifm 2010 (sec-b)
PPT
International economic ch02
PPTX
Cost Comparative Theory
PPT
Foundations of Modern Trade Theory
PDF
Module II theories of international Trade.pdf
PPT
krugman_PPT_c03.ppt
PPT
Law of Comparative Advantage by Dominick Salvatore
PDF
C03 Krugman Labor productivity and Comparative Advantage: The Ricardian Model
PPT
International Trade hs
PPT
Classical Theory Of International Trade
PPTX
International Economics
PPT
International marketing of Agri-products
PPT
International trade
PPTX
International Trade
PPTX
Tadele Power Point.pptx
PPTX
Standard Theory
PPTX
Micro ch9 ppt
PDF
Comparative Advantage
Economic conditions and international tradeMBA 681 Economi.docx
CLASSICAL THEORY OF TRADE OR David RIcardo's theory of international trade.pptx
Ifm 2010 (sec-b)
International economic ch02
Cost Comparative Theory
Foundations of Modern Trade Theory
Module II theories of international Trade.pdf
krugman_PPT_c03.ppt
Law of Comparative Advantage by Dominick Salvatore
C03 Krugman Labor productivity and Comparative Advantage: The Ricardian Model
International Trade hs
Classical Theory Of International Trade
International Economics
International marketing of Agri-products
International trade
International Trade
Tadele Power Point.pptx
Standard Theory
Micro ch9 ppt
Comparative Advantage
Ad

Recently uploaded (20)

PPTX
The discussion on the Economic in transportation .pptx
PPTX
Session 3. Time Value of Money.pptx_finance
PDF
Corporate Finance Fundamentals - Course Presentation.pdf
PDF
discourse-2025-02-building-a-trillion-dollar-dream.pdf
PDF
CLIMATE CHANGE AS A THREAT MULTIPLIER: ASSESSING ITS IMPACT ON RESOURCE SCARC...
PDF
how_to_earn_50k_monthly_investment_guide.pdf
PPT
E commerce busin and some important issues
PPTX
EABDM Slides for Indifference curve.pptx
PPTX
social-studies-subject-for-high-school-globalization.pptx
PDF
Bitcoin Layer August 2025: Power Laws of Bitcoin: The Core and Bubbles
PDF
Dialnet-DynamicHedgingOfPricesOfNaturalGasInMexico-8788871.pdf
PDF
DTC TRADIND CLUB MAKE YOUR TRADING BETTER
PDF
6a Transition Through Old Age in a Dynamic Retirement Distribution Model JFP ...
PDF
NAPF_RESPONSE_TO_THE_PENSIONS_COMMISSION_8 _2_.pdf
PDF
Predicting Customer Bankruptcy Using Machine Learning Algorithm research pape...
PDF
Chapter 9 IFRS Ed-Ed4_2020 Intermediate Accounting
PDF
ECONOMICS AND ENTREPRENEURS LESSONSS AND
PDF
Lecture1.pdf buss1040 uses economics introduction
PDF
How to join illuminati agent in Uganda Kampala call 0782561496/0756664682
PPTX
Session 11-13. Working Capital Management and Cash Budget.pptx
The discussion on the Economic in transportation .pptx
Session 3. Time Value of Money.pptx_finance
Corporate Finance Fundamentals - Course Presentation.pdf
discourse-2025-02-building-a-trillion-dollar-dream.pdf
CLIMATE CHANGE AS A THREAT MULTIPLIER: ASSESSING ITS IMPACT ON RESOURCE SCARC...
how_to_earn_50k_monthly_investment_guide.pdf
E commerce busin and some important issues
EABDM Slides for Indifference curve.pptx
social-studies-subject-for-high-school-globalization.pptx
Bitcoin Layer August 2025: Power Laws of Bitcoin: The Core and Bubbles
Dialnet-DynamicHedgingOfPricesOfNaturalGasInMexico-8788871.pdf
DTC TRADIND CLUB MAKE YOUR TRADING BETTER
6a Transition Through Old Age in a Dynamic Retirement Distribution Model JFP ...
NAPF_RESPONSE_TO_THE_PENSIONS_COMMISSION_8 _2_.pdf
Predicting Customer Bankruptcy Using Machine Learning Algorithm research pape...
Chapter 9 IFRS Ed-Ed4_2020 Intermediate Accounting
ECONOMICS AND ENTREPRENEURS LESSONSS AND
Lecture1.pdf buss1040 uses economics introduction
How to join illuminati agent in Uganda Kampala call 0782561496/0756664682
Session 11-13. Working Capital Management and Cash Budget.pptx
Ad

Basics of International Trade.ppt

  • 2. TWO BASIC QUESTIONS IN INTERNATIONAL TRADE: 1) WHAT DETERMINES INTERNATIONAL TRADE? 2) WHY COUNTRIES WOULD GAIN FROM TRADE?
  • 3. Historical Development of Trade Theory  Mercantilism – positive trade balance  Absolute advantage (Adam Smith) – Countries benefit from exporting what they make cheaper than anyone else  Comparative advantage (David Ricardo) – Nations can gain from specialization, even if they lack an absolute advantage Foundations of trade theory
  • 4. Absolute Cost Advantage Theory (Adam Smith) Assumptions: 1) Labour Theory of Value 2) Free Trade Country 1 Unit of A 1 Unit of B I 10 20 II 20 10 Labour Cost of Production (in Hours) The Difference on absolute cost of producing the commodities between the two countries in isolation will serve a useful basis for opening up of mutually gainful international trade between two countries.
  • 5. David Ricardo Theory of Comparative Cost Advantage Basis of International Trade is the comparative cost differences between two countries. According to this theory, Adam Smith’s Absolute Cost Advantage Theory is not quite unambiguous proposition. Cases may arise where any one country may enjoy absolute advantage over other country in both the goods. Under such circumstances still trade may occur given that there exists comparative cost difference.
  • 6. Example Labour Cost (in Hours) for 1 unit of production Country Wine Cloth Portugal 80 90 England 120 100 Portugal has absolute advantage in both cloth and wine over England. According to Ricardo trade is still worthwhile due to comparative cost difference. In Portugal, 1 unit of wine= 8/9 units of cloth, where as it is 12/10 in England. So, opportunity cost of production of 1 unit of wine in Portugal is 8/9 units of cloth but in England it is 12/10. So, Portugal enjoys comparative cost advantage in production of wine.
  • 7. Country Wine Cloth Portugal 80 90 England 120 100 Reference Table Country Wine Cloth Portugal 8/9 9/8 England 12/10 10/12 Opportunity Cost* for *The opportunity cost for good X is the amount of other goods which have to be given up in order to produce one additional unit of good X. Thus Portugal has lower opportunity cost of the two countries in producing wine while England has lower opportunity cost in producing cloth. So, Portugal has a comparative advantage in production of wine and England has an advantage in production of cloth.
  • 8. So, in this case Comparative cost serve as an useful basis for opening up of a gainful international trade between Countries. Each country seeks here to specialise in production and export of the commodity in which it has comparative advantage and wants to import the other commodity from its trading partner.
  • 9. Live Example Suppose, India 1US$= Rs. 50 Tanzania 1US$= Tnz Shilling 1000 (Rates are assumed for simplification of calculation) Water Beer Pw/Pb India Rs. 10 Rs. 30 1/3 Tanzania Ts. 500 Ts. 700 5/7 In terms of absolute cost, both water and beer are cheaper in India Suppose both the countries decide for a price ratio of ½, then India will gain in selling water and Tanzania in Beer. Explanation: Domestically in India a person has to sell 3 bottles of water to get a bottle of beer but if he buys from Tanzania, he requires to exchange only 2 bottles of water to get 1 bottle of beer. On the other hand in Tanzania when a person sells a bottle of beer he/she gets slightly more than a bottle of water, but if the beer bottle is sold internationally to India, the gain is more as the person will get full 2 bottles of water in return.
  • 10. Transformation schedules or Production Possibility  Generalizes theory to include all factors, not just labor  Shows combinations of products that can be made if all factors are used efficiently  Slope, or marginal rate of transformation, shows the opportunity cost of making more of one good (how much of one good must be given up to make more of another) Comparative advantage
  • 11. The opportunity cost version of Comparative cost: The concept of Production Possibility Curve (PPC) Wheat Cloth The concept of Opp. Cost can be described through PPC. This shows alternative combination of any two products that can be produced efficiently with given resources and technology. In virtue of full employment and efficient use of resources, it is true that PPC will be downward slopping. But it may either a straight line or concave or convex curve to the origin. . Slope of PPC measures marginal opp. Cost of producing one commodity in terms of others
  • 12. Wheat Cloth Under condition of constant cost in production PPC becomes a straight line. Again if law of increasing cost is operating then PPC will be concave. This is so because factors of production may not be adaptable completely to the two alternative use. In case of decreasing cost condition in production, PPC will be convex to the origin
  • 13. Marginal Rate of Transformation 0 10 20 30 40 50 60 70 0 20 40 60 80 100 120 140 Autos A B C Slope = MRT = 0.5 Wheat
  • 14. Wheat Cloth PPC and Price Line Under constant cost condition PPC coincides with the price line* But this is not so in case of varying cost condition because in this case cost alone does not determine the prices. We have to consider the demand conditions also. Given the internal demand condition we need to draw a separate price line whose slope will represent the ratio of exchange between goods. *The slope of the Price line denotes the relative price ratio of two products.
  • 15. Indifference curves  Final pattern of trade depends not just on supply, but also on demand - which is determined by individual tastes  Tastes can be shown graphically with indifference curves, which show the various combinations of two goods that give a consumer the same total level of satisfaction Bringing demand into the model
  • 16. A consumer’s indifference map 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 8 9 Autos Bringing demand into the model A B C D E I II III Wheat
  • 17. Indifference curves (cont’d)  “Higher” indifference curves (those farther from the origin) represent greater levels of satisfaction  Individual preferences cannot really be added up into a “community indifference curve” but it is useful to imagine that they can for the purposes of trade theory Bringing demand into the model
  • 18. Indifference curves (cont’d)  Indifference curves have a negative slope – Keeping satisfaction constant means giving up some of one good for more of another  Indifference curves are convex – As the consumer gets more of one good, she is less willing to give up what is left of the other – The rate of substituting one good for another is shown by the slope of the curve, the marginal rate of substitution Bringing demand into the model
  • 19. Equilibrium Black Line: Price Ratio Red Curve: PPC Green Curves: Community Indifference curve (CIC), denotes preference pattern of the community Equilibrium A Community’s demand pattern is described by its CICs. Production of the goods by PPC. Price ratio by the price line. Y X Equilibrium occurs at R which we call the point of autarky or equilibrium in absence of international trade. At this point. PPC becomes tangent to the highest achievable CIC (and also price line). R