Chương 2: Suy nghĩ như một nhà kinh tế học
- Science is about how the world works (positive) and should work
(normative)
- Natural science is about natural world, and science is about human society.
- Economy is about how the economy world works (positive) and should
work (normative)
- Microeconomics behaviors
- Microeconomics aggregation of microeconomics behaviors
- A theory is an explanation of a fact (information)
+ Right or wrong, data will decide.
- Evidence is an establishment of a fact (deeper information)
+ Right or wrong, methods will decide.
- Theory as model
+ A model is a form of theory
+ Simplification by assuming away
+ A simplified representation of reality
+Pros: Focus on targeted aspects
+Cons: Miss the whole picture.
- Science is a full of models.
- A model
+ Frank and Ruby
+ works 8hrs/day
+Produce meat and potatoes
+Frank :60mins of meat and 15mins of potatoes
15x+60y=480
+ Ruby: 20mins of meat and 10mins of potatoes
- Specialization is the key.
- Absolute advantage you are the best.
- Opportunity cost (Oc)
- Comparative advantage : you do what you do best in terms of Oc
- Mức giá đến từ đâu?
- Why people so good ?
Market and Elasticity
-What determines the price ?
+ Price theory: buyers and sellers (today)
+ Government policies
- Buyers
- Comperative market : price is given
- Maximize satisfaction
- The law of demand
- Movement along the curve
- Demand shift = nhu cầu chuyển dịch
- Income
+ Normal good
+ Inferior good
- What else ?
+ Subtitutes (hàng hóa thay thế) and complements (hàng hóa bổ sung cho nhau)
+ Tastes, expectations, no.of buyers
- Elasticity (Hệ số co giãn)
+ Elasticity of demand
+ Price elasticity of demand = percentage change in quantity demanded /
percentage change in price
- Phương pháp mid-point
- What determine price elasticity
+ Hàng hóa thiết yếu nên dù giá có tăng thì vẫn đc tiêu thụ => hệ số co giãn thấp
+ Phụ thuộc vào nhu cầu của buyers
- Profit = Revenue – cost
- Sellers (
GOVERNMENT AND EFFICIENCY
*Government policies
- Nhà nước ko thể kiểm soát đc giá ở thị trường
- Should the government use price ceiling ?
+ Can’t protect the low-income consumers
+ Not good
- Bên nào co giãn càng ít thì càng đóng nhiều thuế hơn
-Consumer Surplus
+ Consumer surplus + produce surplus = total surplus
+ Market is efficient
Applications
- Deadweight loss ( tổn thất vô ích )
The law of supply
Introduction
Competitive Market + Profit Max -> The law of supply
- Profit = Total Revenue – Total cost
- Total Revenue = P x Q
- Costs: explicit and implicit
- Accounting profit = Total Revenue – Explicit cost
- Economic profit = Total Revenue – (Explicit – Implicit costs)
Production
- A cookie factory
- Size is fixed (short-run)
- Productio function
+ Output =
- Marginal product ( Sản phẩm biên ): Đầu thêm tăng 1 đơn vị thì đầu ra tăng thêm
1 đơn vị
- Quy luật sản phẩm biên giảm dần
Various measures
- A coffee shop
- Fixed (FC), variable (VC), and total (TC) costs: TC= FC + VC
- Averange fixex (AFC), variable (AVC), and total (ATC) costs: AXC = XC/Q
MONOPOLY
Introduction
Market structure
- Perfect competition
- Monopoly/Monopsony
Monopoly
- Origins
+ Natural monopolies
+ Legal monopolies
MONOPOLISTIC COMPETITION AND OLIGOPOLY
Market structure
- Many sellers
- Product differentiation
- Free entry and exit
Consumer Theory
Setting
- Consumption bundle
