# Wikipedia Authors - Price of Anarchy in Auctions (Highlights)  ## Highlights - There exists a "good" Nash equilibrium in which Alice bids *a* and Bob bids *b*; Alice receives the item and pays *b*. The social welfare is *a*, which is optimal. However, there also exists a "bad" Nash equilibrium in which Alice bids 0 and Bob bids e.g. *a*+1; Bob receives the item and pays nothing. This is an equilibrium since Alice does not want to overbid Bob. The social welfare is *b*. Hence, the PoA is *a*/*b*, which is unbounded.