1. Scarcity & Factors of Production
Welcome to Microeconomics. Everything we study in this course starts with one simple, uncomfortable fact: we cannot have everything we want.
Definition: Economics is the study of how society manages its scarce resources. Scarcity means that society has limited resources but unlimited wants.
Because scarcity exists, every society must answer three fundamental questions:
- What to produce? (Pizzas or Microchips?)
- How to produce? (Robots or Humans?)
- For whom to produce? (Who gets the goods?)
The Ingredients: Factors of Production (CELL)
To produce goods, we need inputs. In economics, these are strictly defined:
| 1. Capital |
Physical Capital: Tools, machines, and factories used to make other goods. Exam Tip: Money is NOT capital. Money buys capital, but produces nothing itself. |
| 2. Entrepreneurship | The risk-taker who combines the other factors to create a business. |
| 3. Land | All natural resources (oil, water, sun, copper). |
| 4. Labor | Human effort and time. |
2. Economic Systems
We know resources are scarce. But who decides how to use them? The method a society uses to answer the "Three Questions" (What, How, For Whom) is called its Economic System.
The Spectrum of Systems
Command Economy
Also known as a Planned Economy (e.g., North Korea, Old Soviet Union).
- Who decides? The Government (Central Authority).
- Ownership: Public (Government) ownership of resources.
- Weakness: Lack of profit incentive = Low innovation and efficiency.
Market Economy
Also known as Capitalism or Free Market.
- Who decides? Individuals (Producers & Consumers).
- Ownership: Private Property rights.
- Key Mechanism: Prices signal scarcity; Profit motivates efficiency.
The Reality: Mixed Economy
Almost every country today (including the US and China) is a Mixed Economy. The market makes most decisions, but the government plays a role (regulations, public goods) to correct market failures.
3. Opportunity Cost & The PPC
Since we have to choose, every choice has a cost. In economics, this isn't just money—it is the value of what you sacrifice.
Opportunity Cost: The value of the next best alternative given up.
Visualizing Trade-offs: The PPC Graph
The Production Possibilities Curve (PPC) shows the trade-offs an economy faces. The classic example is "Guns vs. Butter" (Military vs. Civilian goods).
- Efficiency (Points A & B): Using all resources. To get more Butter, we MUST give up Guns.
- Inefficiency (Point D): Unemployment or idle factories. We can produce more of BOTH.
- Concave Shape: The curve bows out because of the Law of Increasing Opportunity Cost. Resources are not perfectly adaptable.
4. Comparative Advantage & Trade
Why do countries trade? The answer lies in the difference between being the "Best" and being the "Most Efficient."
The Golden Rule: Trade is beneficial if a country specializes in the good where it has a Comparative Advantage (Lower Opportunity Cost).
How to Calculate It
On the exam, identify if the table shows Output or Input.
Case 1: The Output Method (OOO)
"Other Goes Over"
If the data shows quantity produced (e.g., Tons of Wheat):
Case 2: The Input Method (IOU)
"Input Goes Under"
If the data shows resources used (e.g., Hours to make one car):
5. Cost-Benefit Analysis
Economists think "at the margin." We don't look at the total picture; we look at the next step.
Imagine eating pizza. The first slice is great. The third slice makes you sick. Rational people stop when the extra benefit no longer exceeds the extra cost.
The Decision Rule
MB ≥ MC
(Continue until Marginal Benefit equals Marginal Cost)
End of Unit 1 Study Guide.