Glossary
Fixed costs – production costs that are not related to the level of production; also referred to as overhead costs.

Geographical Information System (GIS) – a computer mapping system that links databases of geographically-based information to maps that display the information.  For more information, see www.esri.com.

Market failure – the inability of markets to reflect the full social costs or benefits of a good, service, or state of the world.  Therefore, markets will not result in the most efficient or beneficial allocation of resources.

Net economic benefit – the net economic benefit is the total economic benefit received from a change in the state of a good or service, measured by the sum of consumer surplus plus producer surplus, less any costs associated with the change.

Net Present value – the current value of net benefits (benefits minus costs) that occur over time.  A discount rate is used to reduce future benefits and costs to their present time equivalent.