Perfect competition and monopoly — pricing, profit, and deadweight loss.
24 articles
FeaturedMarket power is the ability of a firm to profitably set price above marginal cost. It is the defining feature of monopoly and oligopoly — and the primary…
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An idealized market of countless tiny sellers, an identical product, and zero pricing power. It rarely exists in full, yet it anchors all of economics.

When you can't set your price, revenue math gets simpler and profit gets brutal. Here's how a price-taker earns, breaks even, or bleeds — with real numbers.

Firms maximize profit where marginal revenue equals marginal cost. Here's what that means, why it's always true, and how to apply it step by step.

Losing money doesn't always mean stop. Economics splits idling temporarily from leaving for good — and the deciding number isn't the one most people watch.

It sounds like doom: competition pushes profit to zero. The reality is subtler, the math reassuring, and the takeaway reshapes how you judge any business.

Monopolies aren't born from being biggest — they're built and defended by barriers that keep rivals out. The main ways control forms, and how it's policed.

A monopolist sets price by holding back output. The numbers behind why a sole seller produces less and charges more than a competitive market would.

Deadweight loss is value that simply vanishes when a monopoly restricts output — trades that would benefit everyone but never happen. Here is how to see it.

Student discounts, airline fares, and bulk pricing are the same trick: charging different buyers different prices for one good. The three degrees, explained.

Some markets are cheapest served by one firm — water, power lines, pipelines. The hard question isn't whether to allow the monopoly, but how to keep it honest.
Perfect competition is a market structure with many sellers, identical products, free entry and exit, and full information.
Read more →Marginal revenue is the additional revenue earned from selling one more unit of output. Its relationship with price determines the firm's market power and its…
Read more →Barriers to entry are factors that prevent new competitors from entering a profitable market.
Read more →Deadweight loss is the reduction in total economic surplus from market inefficiency — units where the benefit to buyers exceeds the cost to sellers that go…
Read more →Antitrust law prevents firms from monopolizing markets, fixing prices, or merging in ways that substantially reduce competition.
Read more →The profit-maximization rule states that firms maximize profit by producing where marginal revenue equals marginal cost.
Read more →The shutdown condition tells a firm when it loses less money by halting production than by continuing.
Read more →Allocative efficiency means resources go to their highest-valued uses (P = MC). Productive efficiency means goods are produced at minimum cost.
Read more →Price discrimination occurs when a seller charges different prices to different buyers for the same good based on their willingness to pay.
Read more →Producer surplus is the difference between the price a seller receives and the minimum price they would have accepted.
Read more →A monopoly is a market with a single seller who faces no close substitutes and sets price above marginal cost.
Read more →Long-run equilibrium is the state a competitive market reaches after all entry and exit adjustments are complete.
Read more →A natural monopoly exists when one firm can supply the entire market at lower cost than two or more competing firms.
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