Cross-Price Elasticity of Demand

Cross-price elasticity of demand measures how demand for one good changes when the price of another good changes, other factors remaining constant. It equals the percentage change in quantity demanded of oil X divided by the percentage change in the price of oil Y. For substitute edible oils, it is positive because a rise in one oil's price encourages consumers to shift towards alternatives.

Mechanism of price transmission

Edible oils such as mustard, soybean, sunflower and palm oil can substitute for one another in cooking and food processing, although imperfectly. Cross-price elasticity links an initial price shock in one market to demand and price changes in the others.

• If the price of oil Y rises, its consumption tends to fall while demand for substitute oil X increases, giving a positive cross-price elasticity.
• Higher demand for oil X raises its equilibrium price when its supply cannot expand immediately. Thus, a shock affecting one oil can produce price co-movement across the edible-oil basket.
• The elasticity measures demand substitution, while the eventual increase in the substitute's price also depends on its supply elasticity, stocks, imports and market adjustment.

Strength and limits of transmission

The magnitude of transmission varies because edible oils differ in taste, processing use, regional preference and suitability for particular foods.

• A high positive value indicates close substitutes, so a price increase in one oil causes a relatively large demand shift towards another.
• A low positive value indicates weak substitution and therefore limited transmission through the demand channel.
• Cross-price elasticity may be asymmetric: a price change in a widely consumed oil can affect another oil differently from the reverse change because market shares and consumer preferences differ.

Relevance for food-price policy

Policymakers must assess edible oils as an interconnected group rather than as isolated commodities. Measures that alter the availability or price of one oil can shift demand towards others, affecting consumer prices, import requirements and the cost of food products using edible oils.