Public Goods and Bads

Very few goods meet the strict characteristics of nonrivalry and nonexcludability. Environmental amenities like clean air or diverse ecological systems

and the

have public good qualities to some degree. However, environmental amenities are sometimes subject to some degree of rivalry or exclusiveness, even if they are better thought of as “public” rather than “private” goods. Figure 7.1 provides a two dimensional representation of alternative degrees of nonrivalry and nonexcludability for different goods.