Seinfeld Economics: The Parking Garage (Public urination)

Cost-benefit analysis involves, whether explicitly or implicitly, weighing the total expected costs against the total expected benefits of one or more actions in order to choose the best or most profitable option. Rational agents are assumed to never take an action for which the expected benefits are less than the expected costs.

From an economist's perspective, making choices involves thinking 'at the margin' - that is, making decisions based on small changes in resources. Doing so leads to the optimal decisions being made, subject to preferences, resources and informational constraints.

A common resource is a type of good consisting of a natural or human-made resource system, whose size or characteristics makes it costly, but not impossible, to exclude potential beneficiaries from obtaining benefits from its use. Unlike pure public goods, common resources face problems of congestion or overuse, because they are rival. Examples of common resources include irrigation systems, fishing grounds, pastures, forests, water or the atmosphere.