stat340: Data and functions for BIAS at NMBU

#' STAT210example2.1: Bond Strength for Portland Cement Mortars
#'
#' An engineer studied a new formulation of Portland cement mortar for
#' shorter cure time and tested the effect the new mixture had on the tension
#' bond strength. In this data set there are a total of 20 samples of bond
#' strength measurements for modified or unmodified mortar. The bond strength is
#' given in kgf/cm\eqn{^2} (kilogram-force per centimetre square).
#'
#' @format A tibble with 10 observations (rows) and 2 variables (columns).
#' \tabular{llllr}{
#'   \tab \bold{Column name} \tab \bold{Data type} \tab \bold{Description} \tab \bold{Values}\cr
#'   \code{[,1]} \tab \code{Modified} \tab numeric \tab Bond strength for modified mortar \tab (16.35 - 17.21)\cr
#'   \code{[,2]} \tab \code{Unmodified} \tab numeric \tab Bond strength for unmodified mortar \tab (16.62 - 17.8)
#' }
#'
#' @details
#'
#' This is data from the Portland Cement example (TABLE 2.1) in Design and
#' Analysis of Experiments, 9th Edition, EMEA Edition.
#'
#' @examples
#'
#' # Stacked data
#' PortlandCement <- stack(STAT210example2.1)
#' names(PortlandCement) <- c('Strength','Modification')
#'
#' # Linear model
#' lm(Strength ~ Modification, data = PortlandCement)
#'
#' @source Montgomery, D. C. (2019) \emph{Design and Analysis of Experiments,
#' 9th Edition, EMEA Edition}. New York: Wiley.
#'
#' @docType data
#' @keywords datasets
#' @name STAT210example2.1
#' @usage STAT210example2.1
#'
"STAT210example2.1"