mxmmod: Measurement Model of Derivatives in 'OpenMx'

#' NLSY97 Longitudinal Depression Scale Data
#'
#' A 5-item depression scale used on the National Longitudinal
#' Survey of Youth, 1997 sample (NLSY97). Individuals were assessed
#' in 2000, 2002, and 2004. All items are assessed on a 4-point
#' likert scale.
#'
#' @format A data frame with 26952 rows and 7 variables:
#' \describe{
#'   \item{pid}{Unique ID of participant}
#'   \item{sex}{Sex of participant}
#'   \item{birth_m}{Birth Month}
#'   \item{birth_y}{Birth Year}
#'   \item{occasion}{Measurement occasion}
#'   \item{nervous}{How often participant felt 'like a nervous person'}
#'   \item{calm}{How often participant felt 'calm and peaceful'}
#'   \item{down}{How often participant felt 'down or blue'}
#'   \item{happy}{How often participant felt 'like a happy person'}
#'   \item{depressed}{How often participant felt 'depressed'}
#' }
#' @source \url{https://www.bls.gov/nls/nlsy97.htm}
"nlsy97depression"