trtools: Miscellaneous Tools for Teaching Statistics

#' Generalized reciprocity in rats. 
#'
#' Data from a study investigating generalized reciprocity in wild-type rats (\emph{Rattus norvegicus}). The rats were trained to pull a stick to produce food for an unfamiliar partner rat. The rats were then put into two conditions in a cross-over design. In one condition the focal rat received help from other rats, while in the other condition they did not. The treatment order was randomized and separated by a four day interval. The number of pulls per minute was recorded for each treatment condition. 
#'
#' @format A data frame 19 observations and three variables:
#' \describe{
#'    \item{rat:}{identifier of focal rat}
#'    \item{help:}{rate of pulls per minute after receiving help}
#'    \item{nohelp:}{rate of pulls per minute after not receiving any help}
#' }
#'
#' @note Rats with the same first digit in their identifier were from the same litter.
#'
#' @source Rutte, C. & Taborsky, M. (2007). Generalized reciprocity in rats. \emph{PLoS Biol}, \emph{5(7)}: e196. doi:10.1371/journal.pbio.0050196.
#' 
"reciprocity"