뒤로Microeconomics: Foundations, Markets, and Elasticity – Study Notes
스터디 가이드 - 스마트 노트
자료에 맞춘 맞춤형 노트, 핵심 정의, 예시, 맥락을 확장해 제공합니다.
Chapter 1: Economics – Foundations and Models
Introduction to Economics
Economy: A system that produces goods and services and distributes them to people.
Two main types of economies:
Market Economy: Individuals and businesses make decisions about production, buying, and selling.
Command Economy: A central authority or government makes major economic decisions.
Microeconomics vs. Macroeconomics
Microeconomics: Studies how individuals and businesses make decisions and interact in markets.
Macroeconomics: Studies the economy as a whole, including aggregate measures like GDP and unemployment.
Basic Economic Concepts
Individual Choice: Decisions people make about how to use their limited resources.
Scarcity: The fundamental economic problem; resources are limited relative to wants and needs.
Four Types of Resources:
Land: Natural resources used in production.
Labor: Human effort used in production.
Capital: Man-made resources (e.g., machines, buildings) used to produce goods and services.
Human Capital: The knowledge, skills, and experience possessed by individuals.
Opportunity Cost: The value of the next best alternative forgone when making a choice.
Trade-Off: Comparing the costs and benefits of different actions.
Decision at the Margin: Deciding whether to do a little more or less of something by comparing additional costs and benefits.
Specialization and Trade
Specialization: Focusing on tasks one is best at performing, increasing efficiency.
Trade: The exchange of goods or services, which can make both parties better off.
Gains from Trade: The benefits that arise from trading with others.
Efficiency, Equity, and Market Failure
Efficiency: Using resources so that it is impossible to make someone better off without making someone else worse off (Pareto efficiency).
Equity: Fairness in the distribution of resources, goods, or benefits.
Market Failure: When the market does not allocate resources efficiently on its own.
Economy-Wide Interaction: Economic decisions by individuals affect others in the economy.
Economic Fluctuations
Recession: A period of declining economic activity, leading to lower spending, income, layoffs, and higher unemployment.
Chapter 2: Trade-Offs, Comparative Advantage, and the Market System
Market Structures
Perfectly Competitive Market: Many buyers and sellers, identical products, no single buyer or seller can influence the price.
Demand
Demand: The willingness and ability of consumers to buy a product.
Demand Curve: Graph showing the relationship between price and quantity demanded (downward sloping).
Demand Schedule: Table showing quantities demanded at different prices.
Quantity Demanded: The amount consumers are willing and able to buy at a specific price.
Ceteris Paribus: Latin for "all other things being equal"; used to isolate the effect of one variable.
Law of Demand: When price increases, quantity demanded decreases; when price decreases, quantity demanded increases.
Shifts and Movements in Demand and Supply
Movement along the curve: Caused by a change in price.
Shift of the curve: Caused by changes in other factors (e.g., income, tastes, prices of related goods).
Types of Goods
Normal Good: Demand increases as income increases.
Inferior Good: Demand decreases as income increases.
Substitutes: Goods that can replace each other; if the price of one falls, demand for the other falls.
Complements: Goods used together; if the price of one falls, demand for the other increases.
Supply
Supply: The willingness and ability of producers to sell a product.
Supply Curve: Graph showing the relationship between price and quantity supplied (upward sloping).
Supply Schedule: Table showing quantities supplied at different prices.
Quantity Supplied: The amount producers are willing and able to sell at a particular price.
Law of Supply: When price increases, quantity supplied increases; when price decreases, quantity supplied decreases.
Market Equilibrium
Market Equilibrium: The point where quantity demanded equals quantity supplied.
Equilibrium Price: The price at which QD = QS.
Equilibrium Quantity: The quantity bought and sold at the equilibrium price.
Competitive Market Equilibrium: Equilibrium in a market with many buyers and sellers.
Shortage: Quantity demanded exceeds quantity supplied (QD > QS).
Surplus: Quantity supplied exceeds quantity demanded (QS > QD).
Chapter 3: Where Prices Come From – The Interaction of Demand and Supply
Consumer Surplus
Consumer Surplus: The difference between what a consumer is willing to pay and what they actually pay; represents the benefit to buyers.
Willingness to Pay: The maximum price a consumer is willing to pay for a good or service.
Formula:
On a graph: Area below the demand curve and above the market price.
To find new consumer surplus after a price change:
Producer Surplus
Producer Surplus: The difference between the lowest price a producer is willing to accept and the price they actually receive; represents the benefit to sellers.
Formula:
(when area is a triangle)
On a graph: Area above the supply curve and below the market price.
To find new producer surplus after a price change:
Producer and consumer surplus can be calculated as the sum of a rectangle and a triangle:
Rectangle:
Triangle:
Economic Surplus (Total Surplus)
Economic Surplus: The total benefit to buyers and sellers from market transactions.
Formula:
Marginal Analysis
Marginal Benefit: The additional benefit from consuming one more unit of a good or service.
Marginal Cost: The additional cost of producing one more unit of a good or service.
Government Intervention
Price Floor: A legally established minimum price that sellers can receive for a good or service (e.g., minimum wage).
Price Ceiling: A legally established maximum price that sellers can charge for a good or service (e.g., rent control).
Measuring Prices
Consumer Price Index (CPI): A measure of the average prices of goods and services purchased by a typical consumer; used to track inflation.
Chapter 4: Elasticity – The Responsiveness of Demand and Supply
Price Elasticity of Demand (PED)
Elasticity: Measures how responsive quantity demanded or supplied is to a change in price.
Formula:
Interpretation:
Elastic (PED > 1): Quantity demanded is very responsive to price changes (flatter demand curve).
Inelastic (PED < 1): Quantity demanded is not very responsive to price changes (steeper demand curve).
Unit Elastic (PED = 1): Percentage change in quantity demanded equals percentage change in price.
Perfectly Inelastic (PED = 0): Vertical demand curve; quantity demanded does not change when price changes.
Perfectly Elastic (PED = ∞): Horizontal demand curve; quantity demanded changes infinitely with any price change.
Total Revenue and Elasticity
Total Revenue (TR): The amount a seller receives from sales.
Formula:
Elasticity affects how total revenue changes with price:
If demand is elastic, lowering price increases total revenue.
If demand is inelastic, raising price increases total revenue.
Midpoint Formula for PED
Midpoint Formula: Used to calculate elasticity between two points.
Formula:
Cross-Price Elasticity of Demand
Cross-Price Elasticity: Measures how a change in the price of one good affects the quantity demanded of another good.
Formula:
Positive value: Goods are substitutes. Negative value: Goods are complements.
Price Elasticity of Supply (PES)
Price Elasticity of Supply: Measures how responsive quantity supplied is to a change in price.
Formula:
Example Table: Types of Elasticity
Type | PED Value | Demand Curve Shape | Interpretation |
|---|---|---|---|
Perfectly Inelastic | 0 | Vertical | Quantity demanded does not change with price |
Inelastic | < 1 | Steep | Quantity demanded changes less than price |
Unit Elastic | = 1 | Intermediate | Quantity demanded changes exactly as price |
Elastic | > 1 | Flat | Quantity demanded changes more than price |
Perfectly Elastic | ∞ | Horizontal | Any price change causes infinite change in quantity demanded |