Chapter 1: Economics: Foundations and Models

Definitions

Economics is the study of how individuals, firms, and societies allocate scarce resources to satisfy unlimited wants. It is divided into two main branches: microeconomics (the study of individual markets and agents) and macroeconomics (the study of the economy as a whole).

• Scarcity: The condition in which wants exceed the resources available to fulfill them.

• Trade-off: The idea that because of scarcity, choosing one thing means giving up something else.

Three Key Economic Ideas

• People are rational: Individuals use all available information to achieve their goals.

• People respond to incentives: Changes in incentives influence behavior.

• Optimal decisions are made at the margin: Decisions are made by comparing marginal benefits and marginal costs.

Efficiency vs. Equality

Efficiency refers to maximizing total output from given resources, while equality concerns distributing resources fairly among individuals.

• Efficiency: Achieved when resources are allocated to their most valuable uses.

• Equality: Achieved when everyone receives the same amount of resources or opportunities.

• Trade-off: Policies that promote equality may reduce efficiency, and vice versa.

Positive vs. Normative Analysis

• Positive analysis: Objective statements about what is, can be tested or validated (e.g., "Increasing the minimum wage will increase unemployment").

• Normative analysis: Subjective statements about what ought to be, based on values (e.g., "The government should increase the minimum wage").

Types of Economies

• Market economy: Decisions are decentralized, made by households and firms interacting in markets.

• Command economy: Decisions are centralized, made by the government.

• Mixed economy: Combines elements of both market and command economies.

Role of Economic Models

Economic models are simplified representations of reality used to analyze economic issues and predict outcomes.

• Assumptions: Models use assumptions to focus on key relationships.

• Purpose: To clarify concepts and test economic theories.

Micro vs. Macro

• Microeconomics: Studies individual agents and markets.

• Macroeconomics: Studies aggregate outcomes such as GDP, unemployment, and inflation.

Chapter 2: Trade-offs, Comparative Advantage, and the Market System

Definitions

• Production Possibilities Frontier (PPF): A curve showing the maximum attainable combinations of two goods that can be produced with available resources and technology.

• Opportunity Cost: The value of the next best alternative foregone when making a decision.

Production Possibilities Frontier (PPF)

The PPF illustrates trade-offs and opportunity costs. Points on the curve are efficient, points inside are inefficient, and points outside are unattainable.

• Shape: Usually bowed outward due to increasing opportunity costs.

• Movement along PPF: Represents trade-offs between goods.

Formula:

Comparative Advantage vs. Absolute Advantage

• Absolute advantage: The ability to produce more of a good with the same resources.

• Comparative advantage: The ability to produce a good at a lower opportunity cost.

Complete Specialization

When each producer specializes in the good for which they have a comparative advantage, total production increases.

Gains from Trade

• Trade allows countries or individuals to consume beyond their own PPF.

• Both parties can benefit if they specialize and trade based on comparative advantage.

Market System

A market system relies on voluntary exchange and prices to allocate resources efficiently.

• Decentralized decision-making through markets.

• Role of prices: Signal information and coordinate economic activity.

Circular Flow Diagram

The circular flow diagram illustrates the movement of resources, goods, services, and money between households and firms.

• Households: Provide factors of production (labor, capital, land) to firms.

• Firms: Provide goods and services to households.

• Money flows: Payments for goods/services and wages/rents/profits.

Chapter 3: Where Prices Come From: The Interaction of Demand and Supply

Definitions

• Market: A group of buyers and sellers for a particular good or service.

• Perfectly competitive market: Many buyers and sellers, no single agent can influence price.

Law of Demand and Law of Supply

• Law of Demand: As price decreases, quantity demanded increases (inverse relationship).

• Law of Supply: As price increases, quantity supplied increases (direct relationship).

Demand Equation:

Supply Equation:

Supply and Demand Curves vs. Quantity Supplied and Quantity Demanded

• Supply/Demand curves: Show the relationship between price and quantity supplied/demanded.

• Quantity supplied/demanded: Specific amount at a given price.

Supply and Demand Schedules

Tables listing prices and corresponding quantities supplied or demanded.

Effect of Change in Price – Change in Quantity Supplied/Demanded

• Change in price: Causes movement along the curve (change in quantity supplied/demanded).

• Change in other factors: Causes shift of the curve (change in supply/demand).

Factors that Shift Demand

• Income (normal vs. inferior goods)

• Prices of related goods (substitutes and complements)

• Tastes and preferences

• Expectations

• Number of buyers

Factors that Shift Supply

• Input prices

• Technology

• Expectations

• Number of sellers

Substitute vs. Complement and Normal vs. Inferior Goods

• Substitute goods: Goods that can replace each other (e.g., tea and coffee).

• Complement goods: Goods consumed together (e.g., peanut butter and jelly).

• Normal goods: Demand increases as income increases.

• Inferior goods: Demand decreases as income increases.

Equilibrium – Identifying and Interpreting

Market equilibrium occurs where quantity demanded equals quantity supplied.

Equilibrium Formula:

Solving for equilibrium price and quantity:

Interpreting Shifts and Double Shifts

• Single shift: A change in demand or supply shifts the equilibrium price and quantity.

• Double shift: Both curves shift; the effect on price or quantity depends on the magnitude and direction of each shift.

Example:

If demand increases and supply decreases, equilibrium price rises, but the effect on equilibrium quantity depends on the relative size of the shifts.