Example
Consider an economy that contains only one good, which everyone likes. Then every allocation is Pareto efficient: the only way to make someone better off is to give them more of the good, in which case someone else will have less of the good, and hence be worse off.Example
An economy contains two people and two goods, apples and bananas. Person1 likes apples and dislikes bananas (the more bananas she has, the worse off she is), and person2 likes bananas and dislikes apples. There are 100 apples and 100 bananas available.The only allocation that is Pareto efficient is that in which person1 has all the applies and person2 has all the bananas. For any other allocation, one of the persons has some units of the good she does not like, and would be better off if the other person had those units.
Example
An economy contains two people and two goods, apples and bananas. Person1 likes apples and doesn't care one way or the other about bananas (she is indifferent between any bundles (a,b) and (a,b'), where a is some number of apples and b and b' are numbers of bananas). Person2 likes bananas and doesn't care one way or the other aboutapples. There are 100 apples and 100 bananas available.The only allocation that is Pareto efficient is that in which person1 has all the apples and person2 has all the bananas. For any other allocation, one of the persons has some units of the good about which she doesn't care; transferring those units to the other person would have no effect her and would make the other person better off.
Example
An economy contains two people and two goods, apples and bananas. Both people like both goods, but value them differently. For person1, 1 apple is exactly equivalent to 2 bananas: she is indifferent between any bundles (a,b) and(a![Examples and exercises on Pareto efficiency (1) Examples and exercises on Pareto efficiency (1)](https://i0.wp.com/www.economics.utoronto.ca/../../symbols/minus.gif)
An allocation is Pareto efficient if and only if
- either person1 has no bananas
- or person2 has no apples.
Three of the allocations that are Pareto efficient are those in which
- person1 has all the apples and person2 has all the bananas
- person1 has all the apples and all the bananas
- person2 has all the apples and all the bananas.