Core Principles of Economics: Scarcity, Markets, and Trade
1. Core Economic Concepts
Scarcity: Wants > Resources → Choice
2. Economics Defined
The study of choices under scarcity and incentives.
3. Micro vs. Macro
- Micro: Individuals and firms.
- Macro: The whole economy.
4. Main Economic Questions
What, how, and for whom to produce? Balancing self-interest vs. social interest.
5. The Three Fundamental Questions
- What: Goods and quantity.
- How: Production method.
- For Whom: Depends on income.
6. Key Definitions
- Tradeoff: Giving up A for B.
- Opportunity Cost: The value of the best forgone alternative.
- Benefit: The gain received.
7. Rational Decision Making
Rational Rule: Choose if benefit ≥ cost.
8. Marginal Analysis
Marginal Cost (MC): Cost of one more unit.
Marginal Benefit (MB): Benefit of one more unit.
Rule: MB ≥ MC.
9. Incentives
Rewards or penalties that change behavior.
10. Economics as a Science
Question → Model → Test.
Tools: Natural experiments, statistical analysis (correlation), and economic experiments.
11. Positive vs. Normative
- Positive: Based on facts.
- Normative: Based on opinion.
12. Production and Global Economy
What to Produce
- Consumption goods: Used now.
- Capital goods: Used to produce future goods.
How to Produce (Factors)
- Land: Natural resources.
- Labor: Work.
- Capital: Tools and machines.
- Entrepreneurship: Organization and risk-taking.
- Human Capital: Skills and education.
For Whom to Produce
Depends on income source: Wage (labor), Rent (land), Interest (capital), Profit (entrepreneur).
Global Economy Dynamics
- Advanced: Rich, service-oriented.
- Developing: Poor, agriculture and manufacturing-oriented.
- Production Differences: Rich nations use more capital; poor nations use more labor.
- Income Inequality: Rich receive more; poor receive less.
- Globalization: Production across countries; firms choose low-cost locations.
Circular Flow Model
Agents: Households and firms.
Markets: Goods market and factor market.
Flows: Real flow (labor to firms, goods to households) and money flow (wages to households, spending to firms). Flows move in opposite directions.
Government Role
Taxes, spending, and transfers.
13. Production Possibilities Frontier (PPF)
The boundary between what we can and cannot produce; illustrates scarcity.
- Attainable vs. Unattainable: On or inside PPF is attainable; outside is unattainable.
- Efficient vs. Inefficient: On PPF is efficient; inside is inefficient.
- Tradeoff vs. Free Lunch: On PPF is a tradeoff; inside is a free lunch.
Opportunity Cost and Growth
- Opportunity Cost: What you give up for one more unit (slope of the PPF).
- Increasing Opportunity Cost: PPF is bowed outward; more production leads to higher costs.
- Ratio Rule: OC of A = units of B given up; OC of B = 1 / OC of A.
- Economic Growth: PPF shifts outward due to better technology, more capital, or better labor.
- Consumption vs. Capital: More capital leads to more future growth but less consumption now.
Trade and Advantage
- Absolute Advantage: Produce more with fewer resources.
- Comparative Advantage: Lower opportunity cost.
- Specialization: Produce what you are best at.
- Trade: Exchange of goods.
14. Market Dynamics
Demand
- Quantity Demanded: Amount buyers are willing and able to buy at a price.
- Law of Demand: Price ↑ → Quantity Demanded ↓; Price ↓ → Quantity Demanded ↑.
- Market Demand: Sum of all individual demands.
- Change in Quantity Demanded: Caused by price change (movement along the curve).
- Change in Demand: Caused by other factors (shift of the curve).
Equilibrium
- Market Equilibrium: Quantity demanded = quantity supplied.
- Equilibrium Price: Price where curves meet.
- Equilibrium Quantity: Quantity bought and sold.
- Shortage: QD > QS → Price ↑.
- Surplus: QS > QD → Price ↓.
Effects of Market Changes
- Demand ↑: Price ↑, Quantity ↑.
- Demand ↓: Price ↓, Quantity ↓.
- Supply ↑: Price ↓, Quantity ↑.
- Supply ↓: Price ↑, Quantity ↓.