Unit 3: Theory of Factor Pricing (A)

1. Land and Labour Markets: Basic Concepts

In microeconomics, the factors of production are the resources used by firms to create goods and services. This unit focuses on the fundamental principles governing the pricing of land and labour.

• Land: Represents all natural resources used in production. Its supply is generally considered fixed by nature.
• Labour: Refers to the human effort—physical and mental—applied to the production of goods and services.

2. Productivity of an Input and Derived Demand

The demand for factors of production differs from the demand for consumer goods.

• Derived Demand: Firms do not demand factors of production for their own sake; rather, the demand for any input is derived from the demand for the final goods it helps produce.
• Input Productivity: The demand for a factor depends on its productivity—specifically, how much an additional unit of that factor adds to the total output.

3. Marginal Revenue Product (MRP)

Marginal Revenue Product is the central concept used by firms to determine how many units of a factor to employ.

MRP = Marginal Physical Product (MPP) × Marginal Revenue (MR)

It represents the change in a firm's total revenue resulting from the employment of one additional unit of a variable factor.

4. Marginal Productivity Theory of Distribution (Wage)

This theory provides a general explanation for factor pricing under competitive conditions.

• The Core Rule: A profit-maximizing firm will continue to hire a factor (like labour) up to the point where the cost of the last unit hired is equal to the revenue it generates.
• Wage Determination: In a competitive labour market, the equilibrium wage rate is equal to the Marginal Revenue Product of the last worker hired.

5. Concept of Rent and Ricardian Theory

Rent is the reward paid for the use of land.

Ricardian Theory of Rent

David Ricardo viewed rent as a "differential surplus" arising from the differences in the quality of land.

• Fixed Supply: Rent exists because the total supply of land is fixed.
• Fertility Levels: Rent is paid on more fertile land because it produces a surplus over the cost of production on the least fertile (marginal) land.
• Price vs. Rent: Ricardo famously argued that high corn prices are not caused by high rents; rather, high rents are a result of high corn prices.

6. Modern Theory of Rent

The modern theory of rent expands the concept beyond land to any factor that is in inelastic supply.

Economic Rent = Actual Earnings - Transfer Earnings

• Transfer Earnings: The minimum payment required to keep a factor in its current occupation (opportunity cost).
• Economic Rent: Any surplus earned by a factor over and above its transfer earnings.