Multiplier and Accelerator | A-Level Economics Model Paragraph (AQA, Edexcel, OCR)

The Multiplier Effect

  • This is when an initial increase in AD leads to further increases in AD.

Example

  • if the government increase spending on state pension
  • this is an increase in G
  • AD = C + I + G + (X-M)
  • so this increase in G leads to a right shift in AD
  • consumers will have an increase in disposable incomes
  • so this would cause an increase in C
  • which would cause AD to increase further
  • this could also cause further increases in consumer spending
  • for example, staff at local cafes and restaurants may get more tips
  • therefore they may increase their consumer spending

What does the multiplier effect depend on?

  • k = 1/(1-MPC)
    • k: multiplier = increase in AD/ initial increase in AD
    • MPC: marginal propensity to consume - how much of an extra £1 would you spend rather than withdraw (save/ spend on imports)

Accelerator effect

  • when there is an increase in economic growth
  • business investment is more likely to increase
  • or vice-versa

Example

  • if businesses are expecting pensioners to spend more money, and
  • if businesses are close to full capacity
  • they will be likely to increase spending on hiring more staff or improving technology/ capital

Another example - Eat Out to Help Out

  • Multiplier effect is when an initial increase in AD leads to further increases in AD.
  • For example
    • government spending increases e.g. Eat Out to Help Out
    • scheme where government spent money to cover half of restaurant bills on certain days
    • this encouraged more people to go out for food after covid
    • greater consumer confidence
    • greater consumer spending on food compared to before
    • greater consumer spending on travel/ tfl/ fuel/ uber/ dessert/ shopping on the way home
    • overall AD increased by more than the initial increase in gov spending
  • k = 1/1-MPC
    • k: multiplier = increase in AD/ initial increase in AD
    • MPC: marginal propensity to consume - how much of an extra £1 would you spend rather than withdraw (save/ spend on imports)
  • Accelerator theory: business spending is more likely to increase after an increase in consumer confidence and consumer spending
  • For example
    • as more people wanted to try new restaurants
    • restaurants could begin to invest in top chefs and top ingredients
    • as they have an expectation of demand