Instead of talking about monopolies, I shall talk about perfect competition.
As all of you know, there are certain conditions that need to be fulfilled in order for perfect competition to exist. Though there is no perfect competition right now in the world, there are some very close examples.
The agriculture market as mentioned in the notes is an approximation of perfection competition due to large number of suppliers and the high subsitutability of products.
Another example is the stock exchange, by design, a stock exchange is a large auction of identical goods with all potential buyers and sellers present and this satisfy the conditions of many buyers and homogeneous product. However, the flaw is that large institutional investors (e.g. investment banks) may solely influence the market price. This violates the condition that no buyer has the ability to influence the market price.
eBay autions may be seen as perfectly competitive as there are very low barriers to entry (anyone can sell a product, provided they have some knowledge of computers and the Internet), many sellers of common products and many potential buyers.
Thus, no market can satisfy all the requirement of this model but some can act as a close approximation.
Yier
