Discuss the nature of the "externality" market failure. what are possible policy responses to remedy this situation? contrast the approaches of pigou (based on taxes or subsidies) and coase (based on assigment of property rights) in your answer, and illustrate by describing a negative externality of your choice and potential policy remedies. if faced with a negative policy externality, would you as an analyst tend to advocate for a pigouvian or coasian approach? what would inflence your decision?