Data are taken from Loomis (2003). The study relates to a survey taken on reported
frequency of visits to national parks during the year. The survey was taken at park
sites, thus incurring possible effects of endogenous stratification.
FormatA data frame with 410 observations on the following 11 variables.
Sourcefrom Loomis (2003)
loomis is saved as a data frame.
Count models typically use anvisits as response variable. 0 counts are included
Hilbe, Joseph M (2007, 2011), Negative Binomial Regression, Cambridge University Press
Loomis, J. B. (2003). Travel cost demand model based river recreation benefit
estimates with on-site and household surveys: Comparative results and a
correction procedure, Water Resources Research, 39(4): 1105
glmlmp <- glm(anvisits ~ gender + factor(income) + factor(travel), family=poisson, data=loomis)
glmlmnb <- glm.nb(anvisits ~ gender + factor(income) + factor(travel), data=loomis)