  A significant part of the United Nations World Heritage Sites (WHSs) is
located in developing countries. These sites attract an increasing number of
tourist and income to these countries. Unfortunately, many of these WHSs are in
a poor condition due to climatic and environmental impacts; war and tourism
pressure, requiring the urgent need for restoration and preservation (Tuan &
Navrud, 2007). In this study, we characterise residents from Shiraz city
(visitors and non-visitors) willingness to invest in the management of the
heritage sites through models for the preservation of heritage and development
of tourism as a local resource. The research looks at different categories of
heritage sites within Shiraz city, Iran. The measurement instrument is a stated
preference referendum task administered state-wide to a sample of 489
respondents, with the payment mechanism defined as a purpose-specific
incremental levy of a fixed amount over a set period of years. A Latent Class
Binary Logit model, using parametric constraints is used innovatively to deal
with any strategic voting such as Yea-sayers and Nay-sayers, as well as
revealing the latent heterogeneity among sample members. Results indicate that
almost 14% of the sampled population is unwilling to be levied any amount
(Nay-sayers) to preserve any heritage sites. Not recognizing the presence of
nay-sayers in the data or recognizing them but eliminating them from the
estimation will result in biased Willingness to Pay (WTP) results and,
consequently, biased policy propositions by authorities. Moreover, it is found
that the type of heritage site is a driver of WTP. The results from this study
provide insights into the WTP of heritage site visitors and non-visitors with
respect to avoiding the impacts of future erosion and destruction and
contributing to heritage management and maintenance policies.
