Economics Content Knowledge (Subject Specialisation)
The Economics content knowledge domain tests whether you can explain SHS microeconomics, macroeconomics and development economics accurately and apply them to Ghana. Questions may ask for definitions, graph reasoning, calculations, policy effects and contemporary examples. You need the logic behind each model, not remembered phrases.
Core rules and concepts
- Scarcity forces choice; every choice has an opportunity cost measured by the next best alternative forgone. A production possibility curve shows trade-offs, efficiency and growth.
- Demand and supply: distinguish a movement along a curve (price change) from a shift (non-price determinant). Equilibrium changes only when a curve shifts.
- Elasticity: PED = %ΔQd ÷ %ΔP; use absolute value for interpretation. Elastic demand (>1) means price cuts raise total revenue; inelastic (<1) means price rises raise revenue. YED distinguishes normal (positive) and inferior (negative) goods; XED signs show substitutes and complements.
- National income: GDP is output produced within borders; GNP/GNI adds net factor income from abroad. Use the expenditure approach GDP = C + I + G + (X − M). Real GDP removes price changes using a deflator; per capita GDP divides by population but ignores distribution.
- Macro policy: fiscal policy uses government spending and taxation; monetary policy uses the policy rate, money supply and credit controls. Inflation, unemployment, the balance of payments and exchange rates interact.
- Development is broader than growth: HDI combines income, education and health; PPP adjusts for cost of living. Ghana's economy is commodity-export dependent (cocoa, gold, oil), with a large services and informal sector, so terms-of-trade and cedi movements matter.
Worked example
A shop sells 100 bags of rice at GHS 5. Price rises to GHS 6 and sales fall to 80. PED = [(80−100)/100] ÷ [(6−5)/5] = (−0.20) ÷ (0.20) = −1. Demand is unit elastic. Total revenue was GHS 500 and is now GHS 480: revenue fell slightly because the percentage price rise equals the percentage quantity fall. Interpretation must use the absolute value (|−1| = 1) and state the revenue implication.
Traps
Do not call GDP “national income” without qualification. Do not treat a price change as a demand shift. Do not reverse the elasticity formula. Do not ignore ceteris paribus. Do not confuse inflation (a rate of price change) with a high price level. Do not list causes of unemployment without linking them to types (frictional, structural, cyclical, seasonal).