The travel cost method of economic valuation, travel cost analysis, or Clawson method is a revealed preference method of economic valuation used in cost–benefit analysis to calculate the value of something that cannot be obtained through market prices (i.e. national parks, beaches, ecosystems).
The aim of the method is to calculate willingness to pay for a constant price facility.
The technique was first suggested by the statistician Harold Hotelling in a 1947 letter to the director of the National Park Service of the United States for a method to measure the benefit of National Parks to the public.
The general principle is that individual visitors spend varying amounts of time and money to access a particular resource.
The further away an individual from the resource, the more time and money they spend and the less frequent is the visit.