On this Picostat.com statistics page, you will find information about the loomis data set which pertains to loomis. The loomis data set is found in the COUNT R package. You can load the loomis data set in R by issuing the following command at the console data("loomis"). This will load the data into a variable called loomis. If R says the loomis data set is not found, you can try installing the package by issuing this command install.packages("COUNT") and then attempt to reload the data. If you need to download R, you can go to the R project website. You can download a CSV (comma separated values) version of the loomis R data set. The size of this file is about 9,685 bytes.
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.
A data frame with 410 observations on the following 11 variables.
number of annual visits to park
income in US dollars per year, categorical: 4 levels
>$25000 - $55000
>$55000 - $95000
travel time, categorical: 3 levels
>=.25 - <4 hrs
loomis is saved as a data frame.
Count models typically use anvisits as response variable. 0 counts are included
from Loomis (2003)
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)
Dataset imported from https://www.r-project.org.