International Trade (AQA A Level Economics)

Revision Note

Test Yourself
Steve Vorster

Expertise

Economics & Business Subject Lead

The Model of Comparative Advantage

  • International trade decreases prices and increases the variety of goods/services available to a nation
    • This results in a higher standard of living

  • Comparative advantage is the theory developed by David Ricardo in 1817 which states that a country should specialise in the goods/services that it can produce at the lowest opportunity cost
    • By specialising, the volume of production increases
    • Excess production can be exported
    • Goods/services which are not produced in the country can be imported

The assumptions of comparative advantage

  • As with any economic model, there are underlying assumptions to the theory of comparative advantage: 
  1. Transport costs are zero: it does not account for moving goods or services between countries. Depending on a nation's location, this is more or less of a problem
  2. There is perfect knowledge: each country knows what it has a comparative advantage in and also the comparative advantages of other countries
  3. Factor substitution is easily achieved: economies can quickly adjust to changing global market conditions by switching from capital to labour - and vice versa
  4. Constant costs of production: the theory does not take into account the economies of scale that can be achieved with an increase in output

Comparative & Absolute Advantage

  • Absolute advantage occurs when a country is able to produce a product using fewer factors of production than another country
    • A country may well have absolute advantage but still not have comparative advantage
      • It should produce goods/services in which it has comparative advantage

  • Production possibility frontiers can be used to illustrate comparative and absolute advantage

Diagram: Production Possibility Frontier for T-shirts & Computers 

4-1-2-specialisation--trade

The production possibility frontiers for 2 countries that both produce two goods 

Diagram analysis

  • Country A has an absolute advantage as it can produce more of both products
  • Country A can produce either 200,000 t-shirts or 100,000 computer chips
    • To produce 100,000 computer chips, it gives up production of 200,000 t-shirts
       
    • The opportunity cost of producing 1 computer chip is

      fraction numerator t minus s h i r t s over denominator c o m p u t e r space c h i p s end fraction
       = fraction numerator 200 comma 000 over denominator 100 comma 000 end fraction = 2 t-shirts

    • The opportunity cost of producing 1 t-shirt is

      fraction numerator c o m p u t e r space c h i p s over denominator t minus s h i r t s end fraction equals fraction numerator 100 comma 000 over denominator 200 comma 000 end fraction
      = 0.5 computer chip

  • Country B can produce either 80,000 t-shirts or 80,000 computer chips
    • To produce 80,000 computer chips, it gives up production of 80,000 t-shirts
       
    • The opportunity cost of producing 1 computer chip is

      fraction numerator t minus s h i r t s over denominator c o m p u t e r space c h i p s end fraction equals fraction numerator 80 comma 000 over denominator 80 comma 000 end fraction
= 1 t-shirts
    • The opportunity cost of producing 1 t-shirt is

      fraction numerator c o m p u t e r space c h i p s over denominator t minus s h i r t s end fraction equals fraction numerator 80 comma 000 over denominator 80 comma 000 end fraction
      = 1 computer chip

  • To produce 1 computer chip Country A gives up 2 t-shirts and Country B gives up 1 t-shirt
    • Country B has a comparative advantage in producing computer chips as it is giving up fewer t-shirts, so it should specialise in computer chip production

  • To produce 1 t-shirt Country A gives up 0.5 computer chips and Country B gives up 1 computer chip
    • Country A has a comparative advantage in producing t-shirts as it is giving up fewer computer chips, so it should specialise in t-shirt production

The gains from trade

  • Comparative advantage shows that by specialising, the volume of production increases
    • Resulting in a large increase in the volume of overall global trade
  • For example: excess production can be exported (Country A exports T-shirts and Country B exports computer chips)
    • Goods/services which are not produced in the country can be imported (Country A imports computer chips and Country B imports T-shirts)

Worked example

Using information from the table below, explain which country should specialise in producing T-shirts and which country should specialise in producing computer chips [2]

 

T-Shirts Computer Chips

Country A

200,000

100,000

Country B

80,000

80,000

Method A

Step1: Cross Multiply and identify highest output

                80,000 x 100,000 = 8,000,000

                200,000 x 80,000 = 16,000,000 [1 mark]
 

Step 2: Using highest output, state who has comparative advantage

                Country A should specialise in producing T-shirts (200,000)

                Country B should specialise in producing computer chips (80,000)

Worked example

Using information from the table below, calculate which country should specialise in producing T-shirts and which country should specialise in producing computer chips [3]

 

T-Shirts Computer Chips

Country A

200,000

100,000

Country B

80,000

80,000

Method B

Step 1: Calculate the opportunity costs for Country A

    • The opportunity cost of producing 1 computer chip is fraction numerator t minus s h i r t s over denominator c o m p u t e r space c h i p s end fraction equals fraction numerator 200 comma 000 over denominator 100 comma 000 end fraction= 2 t-shirts 
    • The opportunity cost of producing 1 t-shirt is fraction numerator c o m p u t e r space c h i p s over denominator t minus s h i r t s end fraction equals fraction numerator 100 comma 000 over denominator 200 comma 000 end fraction= 0.5 computer chip
       

Step 2: Calculate the opportunity costs for Country B

    • The opportunity cost of producing 1 computer chip is fraction numerator t minus s h i r t s over denominator c o m p u t e r space c h i p s end fraction equals fraction numerator 80 comma 000 over denominator 80 comma 000 end fraction= 1 t-shirts 
    • The opportunity cost of producing 1 t-shirt is fraction numerator c o m p u t e r space c h i p s over denominator t minus s h i r t s end fraction equals fraction numerator 80 comma 000 over denominator 80 comma 000 end fraction= 1 computer chip

 

Step 3: State who has comparative advantage in each product

    • Country B has a comparative advantage in producing computer chips as it is giving up fewer t-shirts (1 as opposed to 2) and so it should specialise in computer chip production
    • Country A has a comparative advantage in producing t-shirts as it is giving up fewer computer chips (0.5 as opposed to 1) and so it should specialise in t-shirt production

[2 marks for any correct working and 1 mark for the correct answer]

You've read 0 of your 0 free revision notes

Get unlimited access

to absolutely everything:

  • Downloadable PDFs
  • Unlimited Revision Notes
  • Topic Questions
  • Past Papers
  • Model Answers
  • Videos (Maths and Science)

Join the 100,000+ Students that ❤️ Save My Exams

the (exam) results speak for themselves:

Did this page help you?

Steve Vorster

Author: Steve Vorster

Steve has taught A Level, GCSE, IGCSE Business and Economics - as well as IBDP Economics and Business Management. He is an IBDP Examiner and IGCSE textbook author. His students regularly achieve 90-100% in their final exams. Steve has been the Assistant Head of Sixth Form for a school in Devon, and Head of Economics at the world's largest International school in Singapore. He loves to create resources which speed up student learning and are easily accessible by all.