https://nd.psychstat.org/ 2026-04-28T19:12:29+00:00 https://nd.psychstat.org/ https://nd.psychstat.org/_media/wiki/dokuwiki.svg text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/06box-cox_transformation_for_growth_curve_models Box-Cox transformation for growth curve models Manuscript Data * [NLSY Box-Cox data] * R codes for data plots (2010-03-12) Results Scripts/codes References text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/08multilevel_mediation_model Multilevel mediation model Simple mediation model * Simple mediation model data generation and estimation through re-parameterization Codes * A working example Generate multilevel mediation model data ## Simulate multilevel mediation model data model{ for (i in 1:n){ re[i, 1:5]~dmnorm(mure[i, 1:5], pre_cov[1:5,1:5]) mure[i,1]<-b[1,1]+b[1,2]*w[i] mure[i,2]<-b[2,1]+b[2,2]*w[i] mure[i,3]<-b[3,1]+b[3,2]*w[i] mure[i,4]<-b[4,1]+b[4,2]*w[i] mure[i,5]<-b… text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/09mnarselection_model MNAR selection models Scripts * Growth curve model as MAR * Growth curve model as MNAR * Regression model as MNAR text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/15auxiliary_variables Normal data (MCAR) [,1] [,2] [,3] [1,] 0.0010376 0.01055693 0.1796 [2,] 0.0010274 0.02185791 0.1301 [3,] 0.0000272 0.01532224 0.1451 bias MSE power complete 0.002082 0.01030371 0.174 MLE 0.007537 0.02099279 0.116 Auxiliary text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/16higher_order_invariance manuscript text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/a_working_example ## Estimate a multilevel mediation model model{ for (i in 1:n){ re[i, 1:5]~dmnorm(mure[i, 1:5], pre_cov[1:5,1:5]) mure[i,1]<-b[1,1]+b[1,2]*w[i] mure[i,2]<-b[2,1]+b[2,2]*w[i] mure[i,3]<-b[3,1]+b[3,2]*w[i] mure[i,4]<-b[4,1]+b[4,2]*w[i] mure[i,5]<-b[5,1]+b[5,2]*w[i] for (j in 1:mi[i]){ y[i,j] ~ dnorm(muy[i,j], pre_phi[1]) muy[i,j]<-re[j,1]+re[j,2]/re[j,3]*m[i,j]+re[j,4]*x[i,j] m[i,j] ~ dnorm(mum[i,j], pre_phi[2]) m… text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/growth_curve_model_as_mar #WinBUGS codes generated by BAUW: http://bauw.psychstat.org #USE WITH CAUTION! Model{ # Model specification for linear growth curve model for (i in 1:N){ LS[i,1:2]~dmnorm(muLS[i,1:2], Inv_cov[1:2,1:2]) muLS[i,1]<-bL[1] muLS[i,2]<-bS[1] for (t in 1:5){ y[i, t] ~ dnorm(muY[i,t], Inv_Sig_e2) muY[i,t]<-LS[i,1]+LS[i,2]*t } } #Priors for model parameter for (i in 1:1){ bL[i] ~ dnorm(0, 1.0E-6) bS[i] ~ dnorm(0, 1.0E-6) } Inv_cov[1:2,1:2]~dwish(R[1… text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/growth_curve_model_as_mnar #WinBUGS codes generated by BAUW: http://bauw.psychstat.org #USE WITH CAUTION! Model{ # Model specification for linear growth curve model for (i in 1:N){ LS[i,1:2]~dmnorm(muLS[i,1:2], Inv_cov[1:2,1:2]) muLS[i,1]<-bL[1] muLS[i,2]<-bS[1] for (t in 1:5){ y[i, t] ~ dnorm(muY[i,t], Inv_Sig_e2) muY[i,t]<-LS[i,1]+LS[i,2]*t z[i,t]~dnorm(muz[i,t], 1)I(L[i,t], U[i,t]) muz[i,t]<-b1[t]+b2[t]*y[i,t] L[i,t]<- - (1-m[i,t])*1000 U[i,t]<- m[i,t]*1000 … text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/r_codes_for_data_plots_2010-03-12 ## -----------------------------------------------------------------------------------## ## Box-Cox transformation piat.final<-read.table('nlsy.white.age12.grade7.txt', header=T) dim(piat.final) ## plot of data plot(2:6, piat.final[1, 2:6], ylim=c(min(piat.final[,2:6], na.rm=T),100), type='l') for (i in 2:194){ lines(2:6, piat.final[i, 2:6]) } ## data for box-cox transformation analysis write.table(piat.final[,2:6], 'nlsy.box.cox.txt', row.names=F, quote=F) lambda<-seq(-1, -.1, .1) par(mfr… text/html 2016-01-24T14:48:26+00:00 Anonymous (anonymous@undisclosed.example.com) https://nd.psychstat.org/lab/projects/simple_mediation_model_data_generation_and_estimation_through_re-parameterization ## data generation model{ for (i in 1:n){ y[i]~dnorm(muy[i], pre_y) muy[i]<-iy + b*m[i] + c*x[i] m[i]~dnorm(mum[i], pre_m) mum[i]<-im + a*x[i] x[i]~dnorm(0,1) } } ## population parameter values list(n=500, iy=0, im=0, a=.39, b=.39, c=0, pre_y=1, pre_m=1) ## parameter estimation model{ for (i in 1:n){ y[i]~dnorm(muy[i], pre_y) muy[i]<-iy + b*m[i] + c*x[i] m[i]~dnorm(mum[i], pre_m) mum[i]<-im + a*x[i] } iy~dnorm(0, 1.0E-6) im~dnorm(0, 1.0E-6) a~…