R/acrylic.R

In netSEM: Network Structural Equation Modeling

#' A data frame of an acrylic polymer degradation experiment
#'
#' This data set is from a study of photodegradation of acrylic polymer. 
#' In this work, polymeric samples were exposed to different levels of light exposures and resulting optical changes were determined through optical spectroscopy. 
#' *IrradTot* (total applied irradiance) is the main exogenous variable and *YI* (yellowness index) is the endogenous variable (response). 
#' The other columns in the data set (*IAD1*, *IAD2*, *IAD2p*, and *IAD3*)  are induced absorbance to dose values extracted from optical absorbance spectra as single metrics and used as intermediate unit level endogenous (response) variables in the netSEM analysis. 
#' Photodegradation in a stress and response framework: poly(methyl methacrylate) for solar mirrors and lens. Doi: 10.1117/1.JPE.2.022004
#'
#' @docType data
#' @usage data(acrylic)
#' @name acrylic
#' @author Myles P. Murray, Laura S. Bruckman, Roger H. French
#' 
#' @format A 357 by 6 data frame of continuous variables
#' \describe{
#'   \item{YI}{Yellowness index of acrylic sample}
#'   \item{IrradTot}{Total applied solar irradiance}
#'   \item{IAD1}{Induced Absorbance to Dose of the Fundamental Absorption Edge - Optical absorbance at 275 nm}
#'   \item{IAD2}{Induced Absorbance to Dose of the Tinuvin light stabilizer doublet peak at 298 nm}
#'   \item{IAD2p}{Induced Absorbance to Dose of the Tinuvin light stabilizer doublet peak at 339 nm}
#'   \item{IAD3}{Induced Absorbance to Dose in the yellowing region, at 440 nm}
#' }
#' 
#' @source Solar Durability and Lifetime Extension (SDLE) Research Center, Case Western
#' Reserve University
#' 
"acrylic"