ap macroeconomics mr. lipman introduction to economics modules 1-4 krugman pages 2-30 basic economic...
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AP MACROECONOMICSMR. LIPMAN
Introduction to EconomicsModules 1-4
Krugman Pages 2-30Basic Economic Concepts
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Module 1
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What is Economics in General?
Economics is the study of _________.
• Economics is the science of scarcity and choices.
• Scarcity results because our wants are greater than our limited resources.
• Since we are unable to have everything we desire, we must make choices on how we will use our resources.
• In economics we will study the choices of individuals, firms, and governments.choices
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Economics DefinedEconomics- The study of scarcity and choice.
Macroeconomics- A focus on the overall ups and downs in the economy
Microeconomics- focus is on choices made by individuals or firms.
Examples: You must choose between buying jeans or buying shoes.Businesses must choose how many people to hireGovernments must choose how much to spend on welfare.
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Scarcity: What would parents choose? What would kids choose?
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The Four Factors of Production
Entrepreneurship
Capital
Labor
Land
•Producing goods and services requires the use of resources.•ALL resources can be classified as one of the following four factors of production:
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Land = All natural resources that are used to produce goods and services. Anything that comes from “mother nature.” (Water, Sun, Plants, Oil, Trees, Stone, Animals, etc.)
Labor = Any effort a person devotes to a task for which that person is paid. (manual laborers, lawyers, doctors, teachers, waiters, etc.)
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Two Types of Capital:
1. Physical Capital- Any human-made resource that is used to create other goods and services (tools, tractors, machinery, buildings, factories, etc.)
2. Human Capital- Any skills or knowledge gained by a worker through education and experience (college degrees, vocational training, etc.)
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• Entrepreneurship= ambitious leaders that combine the other factors of production to create goods and services.
• Examples-Henry Ford, Bill Gates, Steven Jobs, Inventors, Store Owners, etc.
Entrepreneurs:1. Take The Initiative2. Innovate3. Take the Risk of Failure
So they can obtain _________.
Profit= Revenue - Costs
PROFIT
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You decide to order a pizza to satisfy the munchies. First, you picked up the telephone and gave your order to the owner that entered it into her computer. This information came up on the chief baker’s monitor in the kitchen and he assigned it to one of his cooks. The cook was busy mixing dough out of salt, flour, eggs, and milk.
The cook finished mixing dough, washed his hands in the sink, and prepared your pizza using tomato sauce, cheese, and sausage. He then placed the pizza in the oven. Within 10 minutes the pizza was cooked and placed in a cardboard box. The delivery person then grabbed your pizza, jumped in the company car, and delivered it to your door.
Classify the Factors of Production in the following scenario:
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Classify the different Factors of Production in the following scenario:
You decide to order a pizza to satisfy the munchies. First, you picked up the telephone and gave your order to the owner that entered it into her computer. This information came up on the chief baker’s monitor in the kitchen and he assigned it to one of his cooks. The cook was busy mixing dough out of salt, flour, eggs, and milk.
The cook finished mixing dough, washed his hands in the sink, and prepared your pizza using tomato sauce, cheese, and sausage. He then placed the pizza in the oven. Within 10 minutes the pizza was cooked and placed in a cardboard box. The delivery person then grabbed your pizza, jumped in the company car, and delivered it to your door.
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Trade-offs and Opportunity CostALL decisions involve trade-offs.
The most desirable alternative given up as a result of a decision is known as opportunity cost.
Trade-offs are all the alternatives that we give up whenever we choose one course of action over others.(Examples: going to the movies or going to a game)
What are trade-offs of deciding to go to college? What is the opportunity cost of going to college?
GEICO commercial assumes you understand opportunity cost. Why?
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Given the following assumptions, make a rational choice in your own self-interest (hold everything else constant)…
1. You want to visit your b/f or g/f for a week2. You work every weekday earning $100 per day3. You have three flights to choose from:
Thursday Night Flight = $275Friday Early Morning Flight = $300
Friday Night Flight = $325
Which flight should you choose? Why?
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Positive vs. Normative
Positive Statements- Based on facts. Avoids value judgments (what is or what will be).Normative Statements- Includes value judgments (what should or ought to be).
How is Economics used? • Economists use scientific method to make generalizations and abstractions to develop theories. Problem is that many economists have different theories and there is no one absolute theory that always works.
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5 Key Economic Assumptions1. Society’s wants are unlimited, but ALL resources are
limited (scarcity).
2. Due to scarcity, choices must be made. Every choice has a cost (a trade-off).
3. Everyone’s goal is to make choices that maximize their satisfaction. Everyone acts in their own “self-interest” and “politics” are always a “real-life” factor.
4. Everyone acts rationally by comparing the marginal costs and marginal benefits of every choice
5. Real-life situations can be explained and analyzed through simplified models and graphs.
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Module 2: Macroeconomics
Employment and the Labor Force
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The Various Business CyclesThe Various Business Cycles
Depression• Recession• Expansion or growth
(which leads to inflation)
• Graph demonstrates changes happening over time as cycles change
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Key Terms used in Macroeconomics
•Nominal income v. Real income (adjusted for inflation)
•Inflation
•Deflation
•Price Stability
•Labor Force = employed+unemployed
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Models are used in Economics to help Models are used in Economics to help explain what is happeningexplain what is happening
•Models (aka graphs)
•Other things equal assumption
•Ceteris Paribus (Latin for “other things equal”)
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The U.S. Unemployment Rate and the Timing of Business Cycles, 1989–2009. Shaded areas
Indicate periods of a recession
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Module 3: The Production Possibility Curve
PPC helps explain efficiency; opportunity costs; and economic growth
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Keys to this ModuleKeys to this Module
• The importance of trade-offs in economic analysis
• What the production possibilities curve model tells us about efficiency opportunity cost, and economic growth
• The two sources of economic growth - increases in the availability of resources and improvements in technology
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When using a PPC always remember that if a point is When using a PPC always remember that if a point is inside or on the curve it is feasible but if it lies inside or on the curve it is feasible but if it lies outsideoutside the curve then it is not feasible. Being on the curve is the curve then it is not feasible. Being on the curve is most efficient (aka no missed opportunites)most efficient (aka no missed opportunites)
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Another PPC example
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This graph represents a constant opportunity This graph represents a constant opportunity cost for a business that makes both cost for a business that makes both calzones and pizzas.calzones and pizzas.
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This graph represent opportunity cost increasing.This graph represent opportunity cost increasing.By producing more pizzas the store owner has to make less By producing more pizzas the store owner has to make less calzones in order to be at maximum efficiency.calzones in order to be at maximum efficiency.
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As more of a good is produced its opportunity cost typically
rises because all inputs are used up and then less adaptable inputs must be used.
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During economic growth the PPC shifts outward but during
A shrinking of economic growth it shifts inward
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Another example of economic growthAnother example of economic growth
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Marginal AnalysisIn economics the term marginal = additional
“Thinking on the margin”, or MARGINAL ANALYSIS involves making decisions based on the difference of additional benefit vs. the additional cost.
For Example:
You have been shopping at the mall for a half hour, the additional benefit of shopping for another half-hour might outweigh the additional cost (the opportunity cost).
After three hours, the additional benefit from staying an additional half-hour would likely be less than the additional cost.
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The MARGINAL ANALYSIS approach to decision making is more commonly used than the “all or
nothing” approach.
Notice that the decision making process wasn’t “should I go to the mall for 3 hours or should I stay home”
In reality the decision making process started with “should I go to the mall at all.”
Once you are there you thought “should I stay for an additional half hour or should I go.”
Marginal Analysis
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The MARGINAL ANALYSIS approach to decision making is more comely used than the “all or
nothing” approach.
Notice that the decision making process wasn’t “should I go to the mall for 3 hours or should I stay home”
In reality the decision making process was “should I go to the mall at all.”
Once you are there you thought “should I stay for an additional half hour or should I go.”
Marginal Analysis
Everyone will continue to do something until
the marginal cost outweighs the marginal benefit. Then they will
stop doing it.
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Module 4: Trade & Comparative Advantage
• Economies always produce more and obtain a higher standard of living when each economy specializes in a specific task and then trades with another. The process of globalization.
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Gains from Trade• The key to a much better standard of living for
everyone is trade.• The reason we have an economy is that there are
gains from trade.• Gains from trade arise from specialization.
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Production Possibilities for Two Castaways: Tom and Hank
28 400
30
9
(a) Tom’s Production Possibilities by himself
Tom’s consumption without trade
Tom’s PPF
Quantity of coconuts
Quantity of fish
Figure 4.1
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1060
20
8
Hank’sPPF
Quantity of coconuts
Quantity of fish
Hank’s consumption without trade
(b) Hank’s Production Possibilities by himselfFigure 4.1
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Tom and Hank’s Individual Opportunity Costs
Tom’s Opportunity Cost
Hank’s Opportunity Cost
One fish ¾ coconut 2 coconuts
One coconut 4/3 fish ½ fish
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• Both castaways are better off when they each specialize in what they are good at and trade.
• Tom should specialize in catching fish.
• Hank should specialize in gathering coconuts.
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28 400
30
910
(a) Tom’s Production and Consumption
Tom’s consumption without trade
30
Tom'sPPF
Quantity of fish
Tom’s consumption with trade
Tom’s production with trade
1060
20
810
Hank'sPPF
Quantity of coconuts
Quantity of fish
(b) Hank’s Production and Consumption
Hank’s production with trade
Hank’s consumption with trade
Hank’s consumption without trade
Quantity of coconuts
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• An individual has a comparative advantage in producing a good or service if the opportunity cost of producing the good is lower for that individual than for other people.
• An individual has an absolute advantage in an activity if he or she can do it better than other people. Having an absolute advantage is not the same thing as having a comparative advantage.
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• Comparative advantage is the basis for trade.– Trade can be beneficial to both even if one has an
absolute advantage in the production of both goods.
By agreeing to specialize and trade, both traders can be better off.
– Everyone has a comparative advantage in something.
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Rich Nation, Poor Nation• Most clothing is made overseas in countries that
are much poorer than the U.S.• The immediate reason for their poverty is that
their economies are much less productive.• Even though these economies are much less
productive, these countries hold a comparative advantage in clothing production.
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• International trade results from comparative advantage.
• If the U.S. concentrates on producing pork and ships some of its output to Canada, while Canada concentrates on aircraft and ships some of its output to the U.S., both countries can consume more than if they insisted on being self-sufficient.
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U.S. consumption with trade
0
1,500
1,000
Quantity of pork (millions of tons)
Quantity of aircraft
(a) The U.S. Production Possibilities Frontier
321
U.S.PPF
U.S. consumption without trade
U.S. consumption without trade
U.S. production with trade
0
3,000
2,000
1,500
10.5 1.5
CanadianPPF
Quantity of pork (millions of tons)
Quantity of aircraft
(b) Canadian Production Possibilities Frontier
Canadian production with trade
Canadian consumption with trade
Canadian consumption without trade
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1.A higher standard of living comes from specialization and trade and thus globalization is ultimately a benefit for all nations economically.
2.Comparative advantage explains the source of gains from trade between individuals and countries.
3.Everyone has a comparative advantage in something.
4. Absolute advantage is the ability to produce a particular good or service better than anyone else.
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