Microeconomics: Core Concepts and Applications – Study Guide

Economic Issues and Concepts

Factors of Production

Factors of production are the resources used to produce goods and services. They are typically divided into four main categories: land, labor, capital, and entrepreneurship.

• Land: Natural resources used in production.

• Labor: Human effort used in production.

• Capital: Tools, machinery, and buildings used to produce goods and services.

• Entrepreneurship: The initiative to combine the other factors and take risks.

Example: In a bakery, the oven (capital), the baker (labor), the flour (land), and the bakery owner (entrepreneurship) are all factors of production.

Opportunity Cost

Opportunity cost is the value of the next best alternative that is forgone when a choice is made.

• Key Point: Every decision involves an opportunity cost.

• Example: If Emma withdraws $10,000 from a savings account earning 5% interest to buy a sewing machine, her annual opportunity cost is $500 (the forgone interest).

Production Possibilities Frontier (PPF)

The PPF is a curve showing the maximum attainable combinations of two products that may be produced with available resources and technology.

• Efficiency: Points on the PPF represent efficient use of resources.

• Opportunity Cost: Moving along the PPF involves shifting resources from one good to another, illustrating opportunity cost.

• Economic Growth: Outward shifts in the PPF indicate economic growth, often due to technological improvements or increased resources.

Equation: Opportunity cost of Good X in terms of Good Y = (Loss of Good Y) / (Gain of Good X)

Economic Theories, Data, and Graphs

Positive vs. Normative Statements

• Positive Statement: Describes the world as it is and can be tested (e.g., "Economic growth leads to higher employment levels").

• Normative Statement: Prescribes how the world should be and involves value judgments (e.g., "Taxes on the wealthy ought to be higher").

Variables in Economics

• Endogenous Variable: A variable explained within a theory.

• Exogenous Variable: A variable determined outside a theory.

• Stock Variable: Measured at a point in time (e.g., wealth).

• Flow Variable: Measured over a period of time (e.g., income).

Demand, Supply, and Price

Law of Demand

The law of demand states that, other things being equal, the quantity demanded of a good falls when the price of the good rises.

• Downward Sloping Demand Curve: Reflects the inverse relationship between price and quantity demanded.

• Income Effect: When the price of a good falls, consumers can buy more with their income, increasing quantity demanded.

• Substitution Effect: When the price of a good falls, it becomes relatively cheaper compared to substitutes, increasing quantity demanded.

Shifts in Demand and Supply

• Rightward Shift in Demand: Indicates an increase in demand at every price.

• Rightward Shift in Supply: Indicates an increase in supply at every price.

Market Equilibrium

Market equilibrium occurs where quantity demanded equals quantity supplied. Changes in demand or supply shift the equilibrium price and quantity.

Price Controls

• Price Ceiling: Maximum legal price; can cause shortages if set below equilibrium.

• Price Floor: Minimum legal price; can cause surpluses if set above equilibrium.

Elasticity

Price Elasticity of Demand

Measures the responsiveness of quantity demanded to a change in price.

• Formula: $\text{Price Elasticity of Demand} = \frac{\% \text{ change in quantity demanded}}{\% \text{ change in price}}$

• Elastic Demand: Elasticity > 1

• Inelastic Demand: Elasticity < 1

• Unit Elastic: Elasticity = 1

Example: If the price elasticity of demand for gasoline is 0.3, a 10% rise in price will result in a 3% decrease in quantity demanded.

Income Elasticity of Demand

Measures the responsiveness of quantity demanded to a change in income.

• Formula: $\text{Income Elasticity of Demand} = \frac{\% \text{ change in quantity demanded}}{\% \text{ change in income}}$

• Normal Good: Positive income elasticity.

• Inferior Good: Negative income elasticity.

Consumer Behaviour

Utility and Marginal Utility

• Utility: Satisfaction or pleasure derived from consuming a good or service.

• Marginal Utility: The change in total satisfaction from consuming one more unit of a good.

• Law of Diminishing Marginal Utility: As more of a good is consumed, the additional satisfaction from each extra unit decreases.

Consumer Choice

• Consumers maximize utility subject to their budget constraints.

• Equilibrium is reached when the marginal utility per dollar spent is equal across all goods.

Producers in the Short Run and Long Run

Short Run vs. Long Run

• Short Run: At least one input is fixed.

• Long Run: All inputs are variable.

Costs of Production

• Fixed Costs: Do not vary with output (e.g., rent).

• Variable Costs: Change with output (e.g., raw materials).

• Total Cost: $\text{Total Cost} = \text{Fixed Cost} + \text{Variable Cost}$

• Average Total Cost: $\text{ATC} = \frac{\text{Total Cost}}{\text{Quantity}}$

• Marginal Cost: $\text{MC} = \frac{\Delta \text{Total Cost}}{\Delta \text{Quantity}}$

Law of Diminishing Returns

As more units of a variable input are added to fixed inputs, the additional output from each new unit will eventually decrease.

Market Structures

Perfect Competition

• Many firms, identical products, free entry and exit.

• Firms are price takers.

• Profit maximization occurs where $\text{MR} = \text{MC}$.

Monopoly

• Single seller, unique product, high barriers to entry.

• Downward-sloping demand curve.

• Profit maximization where $\text{MR} = \text{MC}$, but price is set above marginal cost.

• Can practice price discrimination to increase profit.

Cartels and Price Discrimination

• Cartel: Organization of producers that agree to set prices and output to maximize joint profits.

• Price Discrimination: Charging different prices to different consumers for the same good, not based on cost differences.

Efficiency and Public Policy

Market Failures and Government Intervention

• Market failures occur when resources are not allocated efficiently by the market.

• Government may intervene through taxes, subsidies, price controls, or regulation.

Key Terms and Definitions

Term	Definition
Opportunity Cost	The value of the next best alternative that is forgone when a choice is made.
Factors of Production	Resources used to produce goods and services: land, labor, capital, entrepreneurship.
Production Possibilities Boundary	A curve showing which alternative combinations of output can be attained if all available resources are used efficiently.
Price Ceiling	The maximum permissible price that can be charged for a particular good or service.
Price Floor	The minimum permissible price that can be charged for a particular good or service.
Marginal Utility	The change in total satisfaction caused by consuming an additional unit of a good.
Marginal Cost	The increase in total cost from producing one more unit of output.
Perfectly Competitive Market	A market in which goods and services are traded directly for other goods and services, with many buyers and sellers and no barriers to entry.
Cartel	An organization of producers who agree to act as a single seller to maximize joint profits.
Price Discrimination	Occurs when a firm sells different units of a product at two or more different prices not associated with differences in cost.

Additional info: Some definitions and explanations have been expanded for clarity and completeness.