Assumptions

Question 1

Fixed Simultaneous Entry (Hotelling)

Answer 1

There are 2 firms (A&B) that set a price >=0
Prices are exogenous and such that all consumers will buy (V-k>p)
Firms have marginal costs c>p (where p-c=1) and no fixed costs (f=0)

Question 2

Endogenous Sequential Entry

Answer 2

Any number of firms can enter at a fixed cost of f>=0
Prices are exogenous where all consumer purchase and p-c=1

Question 3

Endogenous prices (Product diff)

Answer 3

There are 2 firms that compete in prices
Locations are exogenous and there is maximum differentiation
All consumer purchase in equilibrium
Normalise marginal costs c=0 and fixed costs f=0

Question 4

Symmetric differentiation

Answer 4

There are 2 firms that compete in prices
Locations are exogenous and there’s symmetric differentiation
All consumers purchase in equilibrium
Normalise marginal costs c=0 and fixed costs f=0

Question 5

Number of Firms (Collusion)

Answer 5

There are n>=2 number of firms that sell homogenous products
Marginal costs are symmetric and equal to c>=0, there are no fixed costs

Question 6

Asymmetries (collusion)

Answer 6

There are 2 asymmetric firms
When they set the same price, As market share is s>=0.5 and B’s market share is (1-s)<=0.5

Question 7

Product differentiation (Collusion)

Answer 7

There are firms that set the same price
They sell differentiated products

Question 8

Equilibrium analysis in Cournot framework

Answer 8

There are n>=1 firms that compete in quantities
Marginal costs are constant c>=0 and no fixed costs f=0
There is linear demand: P=A-BQ (where A>c)

Question 9

Double Marginalisation

Answer 9

There’s a monopoly manufacturer that sets a wholesale price of w>=c
It has marginal costs c>=0 and no fixed costs f=0
There’s a monopoly retailer that sets a price of p
It has marginal costs of w
There is linear demand for the final good: Qr=A-P (where A>c)
A retailer uses 1 unit of the manufacturer good to produce 1 unit of final good
The manufacturer sets w then the retailer makes its choice