Micro S1 Elisa

(1) Equilibrium and efficiency

Individuals: Demand function

What is the Law of Diminishing Marginal Utility

How does the curve on graph look like?

Formula to calculate demand function ✏ explain components

Calculate maximum satisfaction ✏

Firm: Supply function

How to get p: Formula in PPC ✏ (remember you can get Mc from derivating TC)

Shape of the curve - Eco with production : depend on Law of diminishing Marginal utility

Shape of the curve: Eco without prod : depends on technology

Define this law ( note: Marginal product how much unit of output will be produced by adding one unit of input (ex: material..) )

How to get profit function and optimal q ✏ (profit function - derivate)

Graph : shape of curve

Partial Equilibrium : price p* where Supply=Demand

Graph (in terms of p and q) : Demand downwards sloping / Supply upwards sloping

Where is surplus / where is shortage

Surplus calculations

Consumer Surplus ✏

Producer surplus ✏

Total Welfare ✏

How to maximise collective surplus ✏

Economic policies

(2) Equilibrium and efficiency

Definitions

Theorem 1 of Welfare economics concerning general equilibrium in PPC

General equilibrium - no production

New context: 2 goods, 2 markets: consumers own endowments, want to max utility with their BC - solution: exchange goods with other consumers

point w: initial endowment (before exchange) MRS of 2 consumers are no equal / goal exchange to the point when they are equal

have understood the global concept of calculating them / en refaire avec tous les cas d intervention possible / besoin de faire le graph parfaitement ⚠

Determine the general equilibrium 🏁

Maximizing utility for agent A is the how much demand c1 and c2 A is asking for

A will maximise subject to its budget constraint - formula budget consraint ✏

Calculations : you want to get optimum MRS - then isolate the consumption of the good you are not interested in

replace this equation in BC and deduce c1A by calculating

Calculate equilibrium

Note: the BC can also be written as "the excess of demand for con 1 + "" cons 2 =0

This reflects the Walras Law

Context: economy with money

know that supply= initial endowment and demand= c1+c2 (calculate this)

Know equalise Supply and Demand with the values ⚠

Is the trade Beneficial? ⚠

The graph

Indifference curve: combinations of 2 goods when equal satisfaction and utility ⚠

General equilibrium - with production

Difference partial equilibrium and general equilibirum

Pareto optimum

General equilibrium in PPC: 1st fundamental theorem of welfare