Exploring the importance of accounting for on-site sampling and heterogenous preferences simultaneously in estimating aggregate demand function for recreational fishing

Travel cost (TC) data are often collected on-site, raising the question of on-site sampling bias. In addition, the motivations behind visiting a recreational area are diverse and differ across individuals, with the potential implications that preferences for trips are heterogenous. This is particularly true for recreational fishing areas that include multiple sites and within which multiple fishing activities are pursued. Comparing four single-site negative binomial models, this paper shows the importance of accounting for on-site sampling and heterogenous preferences simultaneously. The magnitude of the bias resulting from addressing these two issues separately is examined in terms of variation in consumer surplus, predicted mean trip and price elasticity. The paper further proposes an empirical strategy that addresses the issue of missing income bias. This bias occurs when respondents who do not report their income are significantly different in terms of their trip behavior from those with an average income level.