Week 9 Flashcards
describe oligopoly markets
what is dominant strategy?
a strategy that is best regardless of the other player’s strategy.
e.g. A will confess no matter what B’s strategy is
what is nash equilibrium
set of strategies such that neither player would like to change their action given the other player keeps their action; neither would like to deviate given other players are playing their strategy
Given B lies, A would still like to tell a lie; set of strateiges NOT OUTCOMES
strategies which are best replies to one another
‘equilibrium’ as neither would choose an alternative strategy
why is the outcome pareto ineffcient?
both could be made better off if they both denied
- a coordination problem
- not in self-interest to cooperate
describe incentives to cooperate
how will A and B play in repeated games
a: I will cooperate in the first round. If you cooperate as well, then i will reward you by cooperating in the second round. Or I will defect
B: I will cooperate in the first round. If you cooperate as well, then i will reward you by cooperating in the second round. Or I will defect
So if both firms don’t know when the game will end, they basically treat each round (month) as if the game is infinite and end up cooperating
what is a key feature of oligopoly?
tension between cooperation and self-interest
As a group, best off co-ordinating and acting like a monopolist
produce a small output and charge P>MC
but self-interest leads each firm to not cooperate
what is a duopoly
an oligopoly with 2 firms
consider 2 firms that supply mineral water
Aqua Pure (AP)
Mineral Spring (MS)
Production costs: MC=ATC =0
what does this look like on a graph?
consider 2 firms that supply mineral water
Aqua Pure (AP)
Mineral Spring (MS)
Production costs: MC=ATC =0
what will an efficient outcome look like?
consider 2 firms that supply mineral water
Aqua Pure (AP)
Mineral Spring (MS)
Production costs: MC=ATC =0
what would a monopoly outcome look like?
consider 2 firms that supply mineral water
Aqua Pure (AP)
Mineral Spring (MS)
Production costs: MC=ATC =0
what would a duopoly outcome look like?
consider 2 firms that supply mineral water
Aqua Pure (AP)
Mineral Spring (MS)
Production costs: MC=ATC =0
if they had an incentive to cheat then
Profit(MS) = 40 x $50 = $2000
Profit(before MS) = 30 x 60 = $1800
Profit (AP) = 30 x $50 = $1500
Profit (AP before) = 30 x $60 = $1800
Profit(MS) = 40 x $40 = $1600 Profit(AP) = 40 x $40 = $1600 Profit(Total) = $3200
show how duopoly/oligopoly outcomes lie between monopoly and efficient or competitive outcomes
what happens when there is an increase in firms in oligopoly?