Ch. 1 & 3: Introduction to Economics and the Market System: Supply and Demand

Chapter 1: What is Economics?

Definition and Importance of Economics

• Economics is the study of how individuals and societies allocate scarce resources to satisfy unlimited wants.

• It is important because it helps us understand decision-making, resource allocation, and the consequences of choices.

• Incentive: A reward or penalty that motivates behavior.

• Example: Higher wages act as an incentive for people to work more hours.

Scarcity and Its Role in Economics

• Scarcity refers to the limited nature of resources relative to unlimited human wants.

• Scarcity is encountered everywhere: time, money, natural resources, etc.

• Scarcity affects everyone and is the fundamental problem that gives rise to economic study.

Branches of Economics

• Microeconomics: Studies individual choices and markets (e.g., consumer behavior, firm production).

• Macroeconomics: Examines the economy as a whole (e.g., inflation, unemployment, economic growth).

• Example: Microeconomics analyzes how a firm sets prices; macroeconomics studies national unemployment rates.

The Two Big Economic Questions

• 1. What goods and services are produced, and in what quantities?

• 2. How are these goods and services produced, and who consumes them?

• Globalization: The increasing interconnectedness of economies worldwide.

• Economic Systems: Market economy (decisions by individuals/firms), Command economy (decisions by government), and Mixed economy (combination of both).

• Invisible Hand: Adam Smith's concept that individual self-interest in a free market leads to economic well-being.

Six Key Ideas in Economic Thinking

• Choices are tradeoffs: Choosing one thing means giving up something else.

• Cost-benefit analysis (Rational choice): Weighing additional benefits against additional costs.

• Benefit: The gain or pleasure from an action.

• Opportunity cost: The value of the next best alternative forgone.

• Marginal benefit and marginal cost: The additional benefit/cost from one more unit of activity.

• Choices and incentives: Incentives influence the choices people make.

Types of Economic Statements

• Positive statements: Statements that can be tested and validated (describe 'what is').

• Normative statements: Statements that express opinions or values (describe 'what ought to be').

• Example: 'Unemployment is 5%' (positive); 'The government should reduce unemployment' (normative).

Economic Models and Policy Tools

• Economic model: A simplified representation of reality used to analyze economic issues.

• Economics is used as a policy tool to design and evaluate public policies.

Careers in Economics

• Economics majors can work in finance, government, consulting, research, and more.

• Key skills: Analytical thinking, quantitative skills, communication, problem-solving, and data analysis.

Appendix: Graphing and Equations in Economics

• Types of graphs: Line graphs, bar charts, pie charts, scatter plots.

• Graphs are used to illustrate relationships between variables.

• Calculating slope: Slope measures the rate of change between two variables.

Formula for Slope:

$\text{Slope} = \frac{\text{Change in Y}}{\text{Change in X}} = \frac{\Delta Y}{\Delta X}$

• Linear equations: $Y = a + bX$ where $b$ is the slope and $a$ is the intercept.

Chapter 3: Supply and Demand

Markets and Prices

• Market: Any arrangement that allows buyers and sellers to exchange goods and services.

• Types: Goods markets, services markets, input (factor) markets.

• Competitive market: Many buyers and sellers, none can influence the price.

• Money price: Price in terms of currency; Relative price: Price compared to another good.

Demand

• Demand: The relationship between the price of a good and the quantity consumers are willing and able to buy.

• Quantity demanded: The amount consumers plan to buy at a specific price.

• Law of demand: As price falls, quantity demanded rises (ceteris paribus).

• Income effect: Lower prices increase real income, leading to higher quantity demanded.

• Substitution effect: Lower prices make a good more attractive relative to substitutes.

Demand Curve and Schedule

• Demand curve: Graph showing the relationship between price and quantity demanded.

• Demand schedule: Table listing quantities demanded at various prices.

• Alternative view: Demand curve reflects consumers' willingness and ability to pay.

Changes in Demand vs. Changes in Quantity Demanded

• Change in demand: Shift of the demand curve due to factors like income, tastes, prices of related goods, expectations, number of buyers.

• Change in quantity demanded: Movement along the demand curve due to a change in the good's own price.

Supply

• Supply: The relationship between the price of a good and the quantity producers are willing and able to sell.

• Quantity supplied: The amount producers plan to sell at a specific price.

• Law of supply: As price rises, quantity supplied rises (ceteris paribus).

Supply Curve and Schedule

• Supply curve: Graph showing the relationship between price and quantity supplied.

• Supply schedule: Table listing quantities supplied at various prices.

• Alternative view: Supply curve reflects minimum price producers are willing to accept (based on marginal cost).

Changes in Supply vs. Changes in Quantity Supplied

• Change in supply: Shift of the supply curve due to factors like input prices, technology, expectations, number of sellers, taxes/subsidies.

• Change in quantity supplied: Movement along the supply curve due to a change in the good's own price.

Market Equilibrium

• Equilibrium: The price at which quantity demanded equals quantity supplied.

• At equilibrium, there is no shortage or surplus.

Equilibrium Condition:

$Q_d = Q_s$

Disequilibrium: Surplus and Shortage

• Surplus: Quantity supplied exceeds quantity demanded at a given price; leads to downward pressure on price.

• Shortage: Quantity demanded exceeds quantity supplied at a given price; leads to upward pressure on price.

Shifts in Supply and Demand: Determinants and Effects

• Shifts in demand or supply curves change equilibrium price and quantity.

• Simultaneous shifts can have complex effects; analyze each shift separately and then together.

• Example: An increase in demand (shift right) raises both equilibrium price and quantity, ceteris paribus.

Summary Table: Factors Causing Shifts

Factor	Shifts Demand?	Shifts Supply?
Income	Yes	No
Price of related goods	Yes	No
Tastes/Preferences	Yes	No
Input prices	No	Yes
Technology	No	Yes
Number of buyers/sellers	Yes (buyers)	Yes (sellers)
Expectations	Yes	Yes

Additional info: Figures and tables referenced (e.g., 3.1, 3.2, 3.3, etc.) typically illustrate demand and supply curves, shifts, and equilibrium adjustments. Students should refer to their textbook for graphical representations.