Question 1

What defines an oligopoly market structure?

Accepted Answer

An oligopoly is a market structure with few large firms dominating the market, each holding substantial market share. These firms typically offer similar or identical products. High barriers to entry—such as high investment costs, regulations, or control over scarce resources—prevent new competitors from easily entering the market, allowing oligopolistic firms to maintain supernormal profits.

Question 2

How does firm interdependence affect pricing decisions in oligopolies?

Accepted Answer

In oligopolies, firms are interdependent; one firm's pricing decisions significantly impact competitors' market share and profits. Firms often avoid competing on price because lowering prices triggers retaliatory cuts, leading to price wars, while raising prices risks losing customers. Instead, firms focus on non-price competition through advertising, product differentiation, and customer service to gain market advantage.

Question 3

Why do oligopolistic firms prefer non-price competition?

Accepted Answer

Oligopolistic firms prefer non-price competition because price competition can trigger destructive price wars that reduce profits for all competitors. Instead, firms differentiate products through branding, quality improvements, and extensive advertising campaigns. This strategy allows firms to compete for market share without triggering retaliatory price cuts, maintaining price rigidity and protecting profit margins.

Question 4

What are the negative effects of oligopoly on consumers and markets?

Accepted Answer

Oligopolies can increase prices, reduce innovation, and limit consumer choices due to limited competition. Prices often remain above marginal cost, creating inefficiencies. The concentration of market power with few competitors restricts the variety of products available and reduces incentives for firms to innovate or improve service quality, ultimately harming consumer welfare.

Question 5

What is the difference between a duopoly and an oligopoly?

Accepted Answer

A duopoly is a specific type of oligopoly with exactly two sellers in an industry. An oligopoly, more broadly, is characterized by few sellers—typically more than two—holding substantial market share. Both market structures feature firm interdependence, barriers to entry, and price rigidity, but duopolies represent the most concentrated form of oligopolistic competition.

Question 6

How do barriers to entry sustain oligopolistic market power?

Accepted Answer

Barriers to entry prevent new competitors from entering oligopolistic markets, allowing existing firms to maintain market dominance and supernormal profits long-term. These barriers can be economic (high startup costs), legal (patents and licenses), or strategic (control of scarce resources). Without new entrants to challenge market power, oligopolistic firms can sustain pricing above competitive levels.

Question 7

What strategic behaviors do oligopolistic firms use to manage competition?

Accepted Answer

Oligopolistic firms engage in strategic behavior including tacit collusion to avoid price wars or explicit cartels to maximize collective profits, though the latter is often illegal. Firms also compete through product differentiation, branding, and quality improvements. These strategies reflect the mutual dependence among firms, where decisions by one firm directly affect competitors' profitability and market positioning.

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