برآورد سود و زیان دوچرخه سواران کوهستان از تغییرات در خصوصیات مسیرها، هزینه های دسترسی، و تعطیلی سایت : آزمایش انتخاب و انتقال منافع

Mountain biking is an increasingly popular leisure pursuit. Consequences are trail degradation and conflicts with hikers and other users. Resource managers often attempt to resolve these problems by closing trails to mountain biking. In order to estimate the impact of these developments, a model has been devised that predicts the effects of changes in trail characteristics and introduction of access fees, and correlates these with biker preference on trail selection. It estimates each individual’s per-ride consumer’s surplus associated with implementing different policies. The surplus varies significantly as a function of each individual’s gender, budget, and interest in mountain biking. Estimation uses stated preference data, specifically choice experiments. Hypothetical mountain bike trails were created and each surveyed biker was asked to make five pair-wise choices. A benefit-transfer simulation is used to show how the model and parameter estimates can be transferred to estimate the benefits and costs to mountain bikers in a specific area.

Tens of millions of North Americans and Europeans own mountain bikes and millions of them are avid trail riders. In the 1990s mountain biking was one of the fastest growing outdoor recreational activities. According to the Bicycle Institute of America, 25 million Americans owned mountain bikes in 1992, a 66% increase from 1990. The Executive Director of the International Mountain Bicycling Association (IMBA, 1994), estimated that in 1994 there were 2
5–3 million avid trail riders in the US. The numbers are much larger today. The growing popularity of mountain biking is also evident through the increased use of public lands by mountain bikers. For instance, the 13-1000 mountain bikers in 1983; 10 years later it was ridden by over 90 000 (IMBA, 1994). The growing popularity of mountain biking in many areas has led to increased trail degradation and conflicts among users on single track. These trails, which are usually 12–24 inches wide, are preferred by many mountain bikers over wider four-wheel drive roads for their greater technical and physical challenge. The conflicts arise because mountain bikers travel at speeds much greater than those of hikers and equestrians. Bikers must slow down, and hikers and equestrians often need to get out of the way. Resource managers have often handled trail degradation and user conflict by closing certain trails or entire sites to mountain biking. For example, in March of 1995, The City Council of Redmond, Washington voted to ban mountain bikes from the city’s Watershed Preserve Area due to concerns of environmental damage (Sprung, 1995).

Experiments were designed to estimate how mountain bikers would value changes in the characteristics of trails. The mountain bikers in our sample displayed reasonable and plausible behavior while choosing between pairs of hypothetical sites. The estimated parameters indicate more single-track is preferred, so is banning other users. Fees, by themselves, would be unwelcome. Trail difficulty is appreciated, but only up to a point. The consumer surplus estimates varied across bikers quite plausibly in terms of household budget, gender and interest in mountain biking. Willingness to pay is a function of income and interest in mountain biking. The results suggest that significant numbers of bikers would be willing to pay an access fee for improved conditions; the amount would depend on the number of substitute sites and the trail characteristics and fees, if any, at those sites. A simulation was used to demonstrate how the parameter estimates could be used in a benefits transfer to value specific changes in the number of sites or the characteristics of existing sites. The results have applicability beyond mountain biking. The study could be used as a template to estimate benefits and costs to other users (hikers and equestrians), a critical component of any analysis of the types of policies managers must consider. Extensions, as discussed above, would include making the choice questions more complex, e.g. having the respondent compare their chosen alternative to an existing site in their choice set and/or asking how often the respondent would ride at the site if it had the conditions described. One could also combine the results of a simple survey such as ours with revealed preference data on existing sites (observed number of rides to each site in the choice set); that is, combine stated preference data