Travel Cost Method Considering Trip-day Counts as Integers

The Travel Cost Method (TCM) is a typical benefit measurement method, using the fact that people substitute the benefit of visiting some sites for their travel cost. However, in the case of tourist sites, travelers do not choose the number of days spent in a tourist city as continuous numbers but integer numbers. We investigate how a bias could arise from ignoring integer numbers of nights in TCM. We derive the formula of what factors constitute the bias. Next, we numerically show that when measuring benefits of improving quality at sites, the maximum bias could be around 20%.