The meaning of market equilibrium

Market equilibrium occurs when the amount of a good or service supplied matches the amount demanded at a particular price. This balance ensures that prices and quantities remain steady, with no pressure for change.

Key features of market equilibrium:

• At equilibrium, all goods offered for sale are purchased, clearing the market completely.
• In a free market, this point is determined by the interaction of supply and demand forces.
• The equilibrium price and quantity are found where the supply curve intersects the demand curve on a diagram.

Market disequilibrium arises when supply and demand do not balance, leading to either too much supply or too much demand.

Excess supply and excess demand

When markets are not in equilibrium, imbalances create pressure for prices to change, restoring balance through natural adjustments in a free market.

Excess supply

• Excess supply happens when more of a product is supplied than demanded at the current price.
• This typically occurs if the price is set above the equilibrium level.
• As a result, prices fall to encourage more demand and reduce supply until equilibrium is achieved.

Excess demand

• Excess demand occurs when more of a product is demanded than supplied at the current price.
• This often happens if the price is set below the equilibrium level.
• Consequently, prices rise to decrease demand and increase supply until equilibrium is restored.

In a free market, these imbalances are temporary as market forces automatically adjust to eliminate them.

Effects of shifts in demand and supply curves

Changes in factors affecting demand or supply cause their curves to shift, leading to new equilibrium points with altered prices and quantities.

Demand curve shifts

• Increase in demand - The demand curve shifts right, raising the price and expanding supply to a new equilibrium.
• Decrease in demand - The demand curve shifts left, lowering the price and contracting supply to a new equilibrium.

Supply curve shifts

• Increase in supply - The supply curve shifts right, reducing the price and extending demand to a new equilibrium.
• Decrease in supply - The supply curve shifts left, increasing the price and contracting demand to a new equilibrium.

These shifts demonstrate how external changes, like consumer preferences or production costs, influence market outcomes.

The influence of elasticity on market changes

Price elasticity of demand and supply determines how much equilibrium price and quantity adjust when demand or supply curves shift.

How elasticity affects demand shifts

• Along an elastic supply curve, a demand shift mainly changes quantity, with a smaller impact on price.
• Along an inelastic supply curve, a demand shift primarily affects price, with less change in quantity.

How elasticity affects supply shifts

• With elastic demand, a supply shift has a greater effect on quantity than on price.
• With inelastic demand, a supply shift impacts price more than quantity.

In general, inelastic curves lead to larger price fluctuations, while elastic curves result in bigger quantity changes during market adjustments.

Assumptions of the demand and supply model

The demand and supply model simplifies market behaviour but relies on specific assumptions that limit its real-world application.

Key assumptions in the model:

• Supply and demand operate independently without influencing each other directly.
• Markets are perfectly competitive, with many buyers and sellers acting freely.
• Ceteris paribus holds, meaning all other variables remain unchanged.

Limitations and benefits of the model:

• These assumptions make the model less accurate for complex real-world scenarios.
• Despite this, the model offers a straightforward framework for understanding basic supply and demand dynamics.