An article recently posted in the Economic Times, talks about how Yahoo has recently updated its search engine with better filters that should help users find what they are looking for easier by using advanced filters that weed out unrelated information. The article gave the example of using the word Paris and hotels in a search by saying that the new search engine will assume that the user is looking for hotels in Paris and not the latest gossip on Paris Hilton.
I think that this is a good example to demonstrate externalities. Because anything change that a search engine employs will result in externalities for users and/or the people or business that have websites and information posted on the internet. The new filters that Yahoo is using will result in positive externalities for say, the hotels in Paris and those people who are looking to travel to Paris. It will also have negative externalities for the celebrity gossip sites featuring gossip on Paris Hilton and users that are actually looking for celebrity gossip.
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