NETWORK EXTERNALITIES

Till this point we have assumed that people's demands for good are independent of each other.

Actually, a person's demand can be affected by the number of other people who have purchased that good.

If this is the case, a network exists externality.

Network externalities can be negative or positive.

A positive network exists externality if the quantity of a good demanded by a consumer increases in response to an increase in the purchases by other consumers.

Negative network externalities are the opposite of it.