Ebay has been around for about 23 years and has been a big competitor in their market.
Which is why Ebay is considered to be an oligopoly because of market dominance by few firms,
having barriers to entry, and using the game theory.
To begin with, the difference between all the market structures are that in a perfect
competition market there are large number of firms, free entry or exit, and produce similar
products. In a monopoly there is only one firm that sells a unique product in the market. In a
monopolistic competition there are many firms but producers can sell products that are different
from one another. Lastly, in an oligopoly there are a small number of firms that dominate the
market and try to put up barriers to entry so other firms wont enter the market. Therefore Ebay is
considered to be an oligopoly because there are few firms that dominate the market. Ebay like
other online commerce sites sell similar products to one another but the only firms that really
