This topic covers the Aggregate Supply (AS) curve, the distinction between short-run and long-run AS, the factors that cause shifts in these curves, and the different theoretical perspectives on the shape of the long-run AS curve.
Aggregate supply (AS) represents the total quantity of goods and services that all firms in an economy are willing and able to produce at a given overall price level in a specific time period. In the Edexcel A-Level Economics syllabus, AS is a fundamental component of the AD-AS model, used to analyse macroeconomic performance, including output, employment, and inflation. Understanding AS is crucial for evaluating how economies respond to shocks and policy changes.
The shape of the AS curve depends on the time horizon and the flexibility of wages and prices. In the short run, the SRAS curve is upward sloping because firms increase output as prices rise, given sticky wages and input costs. In the long run, the LRAS is vertical at the full employment level of output (Y*), reflecting that in the long run, output is determined by real factors like technology, labour, and capital, not the price level. The Keynesian LRAS is horizontal at low output and vertical at full capacity, illustrating demand-deficient unemployment.
Shifts in AS are caused by changes in production costs, productivity, and institutional factors. For example, a rise in oil prices shifts SRAS left (stagflation), while improvements in technology shift LRAS right (economic growth). Mastery of AS is essential for evaluating policies such as supply-side reforms (e.g., deregulation, education) and understanding their impact on potential output and inflation.
Key skills and knowledge for this topic
Key points examiners look for in your answers
Expert advice for maximising your marks
Pitfalls to avoid in your exam answers
Common questions students ask about this topic
Essential terms to know
How questions on this topic are typically asked
Practice questions tailored to this topic