Model Answer
0 min readIntroduction
The conventional economic theory posits that firms aim to maximize profits. This assumption forms the bedrock of many microeconomic models, influencing decisions regarding output levels, pricing strategies, and resource allocation. However, this analysis isn’t universally applicable. The question highlights a specific scenario where the traditional profit maximization framework breaks down: when an entrepreneur sells output in a perfectly competitive market and operates with a production function that exhibits constant returns to scale – mathematically represented as being homogenous of degree one. This implies that scaling up inputs proportionally leads to a proportional increase in output, fundamentally altering the firm’s control over prices.
Understanding the Core Concepts
Profit Maximization: In traditional economic theory, profit maximization occurs where Marginal Revenue (MR) equals Marginal Cost (MC). This implies firms have some degree of control over price, particularly in imperfectly competitive markets. The firm actively chooses the output level that yields the highest difference between total revenue and total cost.
Homogenous Production Function of Degree One: A production function is said to be homogenous of degree one if, when all inputs are increased by a certain proportion, the output increases by the same proportion. Mathematically, this is represented as: Q = f(L, K), where if L is multiplied by 't' and K is multiplied by 't', then Q is also multiplied by 't'. This implies constant returns to scale. A common example is the Cobb-Douglas production function: Q = A * Lα * Kβ, where α + β = 1.
The Breakdown of Conventional Analysis
When a firm operates with a production function homogenous of degree one and sells its output in a perfectly competitive market, several key changes occur:
- Price Taker: In a perfectly competitive market, the firm is a price taker. It cannot influence the market price and must accept the prevailing price.
- Marginal Revenue Equals Price: Because the firm is a price taker, its Marginal Revenue (MR) is equal to the market price (P). MR = P.
- Profit Maximization Condition: The profit maximization condition becomes MR = MC, which simplifies to P = MC.
- The Critical Issue: The production function being homogenous of degree one means that the firm’s cost structure is directly linked to its output level. As output increases, costs increase proportionally. This means the firm’s MC curve is perfectly elastic (horizontal) at the market price.
Implications for Supply Curve and Firm Behavior
The combination of P=MC and a perfectly elastic MC curve has significant implications:
- Supply Curve: The firm’s supply curve becomes perfectly elastic at the market price. It will supply any quantity demanded at that price.
- No Active Decision-Making: The firm doesn’t actively *choose* its output level to maximize profit in the traditional sense. It simply produces the quantity demanded at the given market price. The price is determined by market forces, not by the firm’s individual decisions.
- Long-Run Equilibrium: In the long run, economic profits are driven to zero due to free entry and exit. The firm operates at the minimum point of its Average Total Cost (ATC) curve, but this is a result of market forces, not active profit maximization.
Mathematical Illustration
Let's consider a simple Cobb-Douglas production function: Q = L0.5K0.5. If the firm doubles both labor (L) and capital (K), output (Q) also doubles. If the market price is P, and the firm’s cost of labor and capital are wL and rK respectively, the firm will produce where P = MC. Because of constant returns to scale, the MC curve will be horizontal at the market price, meaning the firm will supply whatever quantity the market demands at that price.
Limitations and Real-World Considerations
While this model provides a theoretical understanding, real-world firms rarely operate under perfectly competitive conditions or with perfectly homogenous production functions. However, it serves as a useful benchmark for understanding the impact of market structure and production characteristics on firm behavior. Factors like product differentiation, barriers to entry, and technological change can all alter the assumptions of this model.
Conclusion
In conclusion, the conventional analysis of profit maximization breaks down when a firm operates with a production function homogenous of degree one in a perfectly competitive market. The firm becomes a price taker, its marginal revenue equals price, and its supply curve becomes perfectly elastic. This fundamentally alters the firm’s decision-making process, rendering the traditional MR=MC profit maximization rule less relevant. The firm’s output is determined by market demand rather than active profit-seeking behavior, highlighting the importance of market structure and production characteristics in shaping firm behavior.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.