Summary By :
Rahadi Sri Rahmanto (120720140028)

This video explained why consumer and producer entering particular market of good or service.  Both the consumer and the producer go to the market because of consumer surplus and producer surplus respectively.

Looking at the supply-demand curve, we could see how much consumer willing to pay for certain quantity of goods as well as how much producer willing to receive in return for certain quantity of goods.

Consumer surplus is the gap between the total utility of a good and its total market value. The surplus arises as result of the law of diminishing marginal utility. According to this law, the earlier units consumed are worth more to us than the last. Consumer surplus indicates the extra value that consumers obtain above what they pay for a good.

Producer surplus is defined as the difference between the amount the producer is willing to supply goods for and the actual amount received by him when he makes the transaction.
For the market as a whole, consumer surplus is visualized by the entire area under the demand curve and above the line representing the purchase price of the good (This reflects the fact that consumers would have been willing to buy a single unit of the good at a price higher than the equilibrium price). Producer surplus, on the other hand, is illustrated by the entire area above the supply curve up to the market price.
The total value of the market (also called measure of welfare)  itself is represented by total surplus which is the summation of the consumer surplus and the producer surplus.

References :
1.    Pindyck, Robert S. & Rubinfeld, Daniel L.2009, Microeconomics. New Jersey : Prentice Hall
2.    Nordhaus, William D. & Samuelson, Paul A. 2010, Economics. New York : McGraw Hill
3.    http://en.wikipedia.org/wiki/Economic_surplus (accessed 31/08/2014)