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growcurves (version 0.2.4.1)

datsimcov: Repeated measures for two groups of subjects drawn from mmcar model with 2 nuisance covariates

Description

A simulation dataset containing repeated subject measures for 2 treatment groups, (control = 0, treatment = 1), constructed from an 'mmcar' model with correlation between adjacent sessions equal to 0.25. Subject effects were randomly drawn from 10 clusters with weights/probabilities drawn from a Dirichlet distribution. Cluster location values were generated from a Gaussian base distribution. Two nuisance demographic variables, age and income, are included.

Usage

datsimcov

Arguments

Format

A list object of 19 variables for 792 total observations on 264 subjects

Details

  • subject. subject identifier (1,2,...,264
  • trt. treatment group identifier of length N (e.g. (0,0,0,...,1,1,1,...) , either {0,1} for control and treatment.
  • time. times in months for each repeated subject measure of length N. There are 3 distinct time points. e.g. (0,3,6,0,3,6,0,0,3,,,,)
  • n.random. number of random effects per subject. Set = 3.
  • n.fix_degree. order of fixed effects. Set = 2, for quadratic, meaning 3 effects (intercept, slope, quadratic) each, for treatment and control groups.
  • coefs. true fixed effect coefficient values used to generate data.
  • subj.aff. indexes subjects receiving treatment.
  • W.subj.aff. multiple membership weight matrix that maps the P_aff = 132 affected subjects (in subj.aff) to any of S = 245 treatment sessions.
  • group. treatment group membership for each of the S sessions.
  • Omega. the S x S CAR adjacency matrix used to model prior dependence among sessions
  • gamma. true session effect values (of length S) used to generate model response.
  • s. true cluster memberships for each of the P subjects.
  • b.star. a list object of true cluster location values for each of M = 10 clusters. Each entry contains the n.random = 3 location values for that cluster.
  • b. a list object true random effect coefficient values for each of P subjects. Each entry contains the n.random = 3 effect values for that subject.
  • tau.b. true values for the prior precisions of the base Gaussian distribution for each of n.random = 3 subject effects.
  • tau.e. true value for overall model error.
  • coefs. true coefficient values for the time-based quadratic fixed effects generated from the trt, and time inputs, as well as the 2 nuisance covariates. e.g. X = c(1, time, time^2, trt_1,trt_1*time, trt_1*time^2, age, income).
  • formula. the additive formula containing the response and nuisance fixed effects. In this case, y ~ age + income.
  • data. (N = 792) x 3 data.frame associated to formula. Includes model response, y, a N = 792 x 1 numeric vector capturing repeated measures for P = 264 subjects. Also contained in data are two nuisance fixed effects, age and income.