Imperfect Competition
Monopolistic competition, oligopoly, and game theory.
25 articles
FeaturedWhat Is an Oligopoly? The Market Structure Where Rivals Think About Each Other
An oligopoly is a market run by a handful of large firms whose decisions are tangled together.
Read more →Deep Dives
10 articles
Returns to Scale: What Happens When You Double Everything in a Production Process
Double every input — does output double, more than double, or less? Returns to scale answers that, and it explains why some industries have giants and others…
What Happens When a Company Doubles in Size? Economies and Diseconomies of Scale
Growing bigger can make every unit cheaper — until it doesn't. Economies of scale pull costs down as a firm expands; diseconomies push them back up.
What Is Monopolistic Competition? The Market Structure Most Businesses Actually Live In
Monopolistic competition is where most real businesses operate: many sellers, easy entry, but each offering something a little different. Here is how it works.
Product Differentiation: The Economic Strategy Behind Every Brand Decision
Product differentiation is how a business escapes the price-taker trap. Here are the economic logic, the four levers, and the math on what a premium is worth.
Short-Run Profit, Long-Run Erosion: What Happens When Rivals Enter Your Market
In monopolistic competition, profit attracts entry, and entry competes the profit away. Follow the chain from a hot launch to the day profit hits zero.
Advertising Isn't Just Persuasion. Here Is What It Actually Does to Markets.
The belief that advertising only manipulates is incomplete. Economists find it also carries real information, signals quality, and can sharpen competition.
Game Theory: The Logic of Strategic Decisions When Your Outcome Depends on Others
Game theory is the math of strategic choice — how to decide when your best move depends on what someone else does.
The Prisoner's Dilemma: Why Rational Rivals End Up Worse Off Together
In the prisoner's dilemma, two players each make the rational choice and both end up worse off.
Cartels, Collusion, and Why Every Price-Fixing Scheme Eventually Breaks Down
Cartels agree to fix prices and act like a monopoly — but each member is tempted to cheat. The economics of collusion, from OPEC to the lysine and vitamins…
Nash Equilibrium: How Strategic Thinking Changed the Way Economists Model Markets
A Nash equilibrium is a stable point where no player can do better by changing strategy alone.
Quick Answers
14 termsCollusion and Cartels: When Competitors Act Like a Monopoly
Collusion occurs when competing firms coordinate on prices, output, or market allocation to raise profits above competitive levels.
Read more →Platform Economics: The Two-Sided Markets That Reshape Industries
Platform economics analyzes two-sided (or multi-sided) markets where a platform intermediary connects two distinct user groups that each benefit from the…
↔ Also in Applied EconomicsRead more →The Network Effect: Why Some Products Become More Valuable as They Grow
Network effects occur when a product's value increases as more people use it. They are the primary driver of winner-take-all market dynamics in technology,…
↔ Also in Applied EconomicsRead more →Economies of Scale: Why Getting Bigger Sometimes Means Getting Cheaper
Economies of scale occur when long-run average cost falls as output increases. They are the economic engine of industrial concentration — and when they're…
↔ Also in The Firm & ProductionRead more →Game Theory: The Framework for Strategic Decision-Making
Game theory analyzes strategic interactions where each player's outcome depends on others' decisions.
Read more →Excess Capacity: The Inefficiency Built Into Monopolistic Competition
Excess capacity is the gap between the output a firm produces and the output at which its average total cost is minimized.
Read more →Price Leadership: How Oligopolies Coordinate Without Colluding
Price leadership is an implicit coordination mechanism in oligopoly where one firm — typically the dominant player — sets price and rivals follow.
Read more →Markup: How Much Above Cost Does a Firm Price?
Markup is the percentage difference between a firm's price and its marginal cost. It measures the degree of market power — competitive firms have near-zero…
Read more →Product Differentiation: How Sellers Escape Pure Price Competition
Product differentiation is the process of distinguishing a product from competitors' offerings through quality, features, branding, design, or customer…
Read more →Oligopoly: A Few Firms, a Lot of Interdependence
An oligopoly is a market dominated by a small number of large firms whose decisions are strategically interdependent — each firm must anticipate how rivals…
Read more →Monopolistic Competition: Many Sellers, Many Products, Zero Long-Run Profit
Monopolistic competition has many firms selling differentiated products with free entry and exit.
Read more →Nash Equilibrium: The Stable Outcome of Strategic Interaction
Nash equilibrium is a set of strategies in which no player can improve their outcome by unilaterally changing their choice.
Read more →The Prisoner's Dilemma: Why Rational Choices Produce Bad Outcomes
The Prisoner's Dilemma is a game in which two rational players each choose a dominant strategy that makes both worse off than if they had cooperated.
Read more →Returns to Scale: What Happens to Output When You Double Everything
Returns to scale describe how output responds when all inputs are increased proportionally.
↔ Also in The Firm & ProductionRead more →