Long Run Equilibrium and Monopoly Insights

Long Run Equilibrium for a Perfectly Competitive Firm

• The discussion begins with the presenter setting up the topic regarding long run equilibrium for a perfectly competitive firm.

• The following graphical elements are introduced:
    - Long Run Average Cost (LAC): The overall shape is not perfectly illustrated but represents average costs in the long run.
    - Marginal Cost (MC): Shown in blue, indicating costs incurred for producing one additional unit.
    - Market Demand and Supply: The demand curve is downward sloping whereas the supply curve is upward sloping, illustrating how market forces determine price.

• Axes Definitions:
    - Y-Axis: Represents price.
    - X-Axis: Represents quantity of goods.

• Emphasis on Price Takers:
    - A perfectly competitive seller does not control the market price and must accept the market equilibrium price.

Equilibrium Price Determination

• The equilibrium in the market occurs where market demand equals market supply.
• The market price is determined at this intersection point.
• For the individual seller, the price at which they sell is equal to:
    - Average Revenue (AR)
    - Marginal Revenue (MR)
    - So, we have the relationship: $p = AR = MR$.

Initial Firm Equilibrium

• The firm’s equilibrium is reached where:
    - Price = Average Revenue = Marginal Revenue = Marginal Cost.
• The initial scenario shows that the firm is making a profit because the price exceeds average cost.

Market Adjustments Due to Profitability

• Due to above-average profits, new firms will enter the market, increasing overall market supply.
• As supply increases, the market price will decrease, leading to adjustments in equilibrium conditions until.

New Market Equilibrium

• Graphically illustrated with a shifted supply curve (new supply in purple) leading to a new equilibrium price:

• This new equilibrium occurs where all firms in the market break even:**
    - Price = Average Revenue = Marginal Revenue = Marginal Cost = Long Run Average Cost (LAC).

• Conclusion from Changes:
    - When firms are making a profit, new entrants reduce price, bringing the market back to a break-even point.

• Any initial losses would also lead firms to exit, driving the price back up to the breakeven.

Long Run Equilibrium Insights

• At the breakeven point, all five critical values are equal:
    - Price
    - Average Revenue
    - Marginal Revenue
    - Marginal Cost
    - Long Run Average Cost (LAC).

Productive and Allocative Efficiency

• Productive Efficiency: Achieved as firms produce at the lowest possible average cost, utilizing economies of scale.
• Allocative Efficiency: Occurs when price equals marginal cost, meaning consumers’ willingness to pay matches the cost of producing the last unit.

Final Conclusion

• In long run equilibrium under perfect competition, firms will end up breaking even, due to the continual entry or exit of firms in response to profits or losses.

Demand Increase Scenario

1. The discussion transitions to impacts of an increase in demand on market equilibrium:
      - If market demand increases, the new demand curve shifts upwards (denoted as D1), leading to a realignment in price and equilibrium:
2. Initial gains in profit due to price increases incentivize new firms to enter the market, eventually returning to a breakeven.

• Flow of adjustments is summarized:
    - Higher demand -> Increased market price -> New firms enter -> Increase in supply -> Return to breakeven market conditions.

Long Run Supply Curve Characteristics

• Constant Cost Industry: The long-run supply curve remains horizontal as costs do not change with increased production.
• Increasing Cost Industry: At some point, increased entry may raise costs, leading to an upward slope in the supply curve.
• Decreasing Cost Industry: Larger production reduces average costs, eventually yielding a downward sloping supply curve.

Transition to Monopoly Discussion

Monopoly Definition

• Transition into the next chapter begins with the definition and features of a monopoly, contrasting it with perfect competition:
    - Single Seller: The market is dominated by one seller.
    - Unique Product:No close substitutes available for consumers.
    - High Barriers to Entry: Difficult for new entrants to compete.
    - Price Maker: The monopolist has control over pricing vs. the price taker in perfect competition.
    - Low Importancy of Advertising: Little need for advertising since there are no competitors.

Barriers to Entry into Monopoly

1. Natural Monopoly: A market structure where one firm can supply the entire market more efficiently than multiple firms.
2. Predatory Pricing: Setting prices low to eliminate competitors, a practice not legal but often enforced.
3. Consumer Convenience: In certain cases, having one provider improves efficiency for consumers.
4. Legal Barriers: Patents grant exclusive rights to produce a good.
5. Control of Resources: Exclusive access to essential production materials limits competitor entry.

Monopoly's Profit Maximization

• Profit maximization occurs at the greatest gap between total revenue and total cost or where:
     - Marginal Revenue (MR) equals Marginal Cost (MC).

Revenue Analysis in Monopoly

• Total Revenue (TR): Calculated as Price times Quantity but unlike perfect competition, varies as price changes due to the downward sloping demand curve.
• Average Revenue (AR): Remains equal to price, calculated as TR divided by quantity.
• Marginal Revenue (MR): Changes with each additional unit sold, falling faster than price due to the necessity of lowering the price for all units sold to attract additional buyers.

Graphical Representation of Revenues

• Marginal revenue curve will fall at twice the rate of average revenue; these differences highlight the inefficiencies within monopoly structures compared to perfect competition.

Conclusion and Next Steps

 - The lesson wraps up with plans to explore short run and long run monopoly in further depth, including price discrimination and government regulations in future sessions.