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sirt (version 1.14-0)

mcmc_coef: Some Methods for Objects of Class mcmc.list

Description

Some methods for objects of class mcmc.list created from the coda package.

Usage

## coefficients mcmc_coef(mcmcobj, exclude = "deviance")
## covariance matrix mcmc_vcov(mcmcobj, exclude = "deviance")
## confidence interval mcmc_confint( mcmcobj, parm, level = .95, exclude="deviance" )
## summary function mcmc_summary( mcmcobj , quantiles=c(.025,.05,.50,.95,.975) )
## plot function mcmc_plot(mcmcobj, ...)
## inclusion of derived parameters in mcmc object mcmc_derivedPars( mcmcobj , derivedPars )
## Wald test for parameters mcmc_WaldTest( mcmcobj , hypotheses )
"summary"(object, digits=3, ...)

Arguments

mcmcobj
Objects of class mcmc.list as created by coda::mcmc
exclude
Vector of parameters which should be excluded in calculations
parm
Optional vector of parameters
level
Confidence level
quantiles
Vector of quantiles to be computed.
...
Parameters to be passed to mcmc_plot. See plot.amh for arguments.
derivedPars
List with derived parameters (see examples).
hypotheses
List with hypotheses of the form $g_i( \bold{\theta})=0$.
object
Object of class mcmc_WaldTest.
digits
Number of digits used for rounding.

See Also

coda::mcmc

Examples

Run this code
## Not run: 
# #############################################################################
# # EXAMPLE 1: Logistic regression in rcppbugs package 
# #############################################################################
# 
# 
# #***************************************
# # (1) simulate data
# set.seed(8765)
# N <- 500
# x1 <- stats::rnorm(N)
# x2 <- stats::rnorm(N)
# y <- 1*( stats::plogis( -.6 + .7*x1 + 1.1 *x2 ) > stats::runif(N) )
# 
# #***************************************
# # (2) estimate logistic regression with glm
# mod <- stats::glm( y ~ x1 + x2 , family="binomial" )
# summary(mod)
# 
# #***************************************
# # (3) estimate model with rcppbugs package
# library(rcppbugs)
# b <- rcppbugs::mcmc.normal( stats::rnorm(3),mu=0,tau=0.0001)
# y.hat <- rcppbugs::deterministic( function(x1,x2,b){
#                 stats::plogis( b[1] + b[2]*x1 + b[3]*x2 ) }, 
#                   x1 , x2 , b)
# y.lik <- rcppbugs::mcmc.bernoulli( y , p = y.hat, observed = TRUE)
# model <- rcppbugs::create.model(b, y.hat, y.lik)
# 
# #*** estimate model in rcppbugs; 5000 iterations, 1000 burnin iterations
# n.burnin <- 500 ; n.iter <- 2000 ; thin <- 2
# ans <- rcppbugs::run.model(model , iterations=n.iter, burn=n.burnin, adapt=200, thin=thin)
# print(rcppbugs::get.ar(ans)) # get acceptance rate
# print(apply(ans[["b"]],2,mean)) # get means of posterior
# 
# #*** convert rcppbugs into mcmclist object
# mcmcobj <- data.frame( ans$b )
# colnames(mcmcobj) <- paste0("b",1:3)
# mcmcobj <- as.matrix(mcmcobj)
# class(mcmcobj) <- "mcmc"
# attr(mcmcobj, "mcpar") <- c( n.burnin+1 , n.iter , thin )
# mcmcobj <- coda::mcmc( mcmcobj )
# 
# # coefficients, variance covariance matrix and confidence interval
# mcmc_coef(mcmcobj)
# mcmc_vcov(mcmcobj)
# mcmc_confint( mcmcobj , level = .90 )
# 
# # summary and plot
# mcmc_summary(mcmcobj)
# mcmc_plot(mcmcobj, ask=TRUE)
# 
# # include derived parameters in mcmc object
# derivedPars <- list( "diff12" = ~ I(b2-b1) , "diff13" = ~ I(b3-b1) )
# mcmcobj2 <- mcmc_derivedPars(mcmcobj , derivedPars = derivedPars )
# mcmc_summary(mcmcobj2)
# 
# #*** Wald test for parameters
#  # hyp1: b2 - 0.5 = 0
#  # hyp2: b2 * b3 = 0
# hypotheses <- list( "hyp1" = ~ I( b2 - .5 )  , "hyp2" = ~ I( b2*b3 ) )
# test1 <- mcmc_WaldTest( mcmcobj , hypotheses=hypotheses )
# summary(test1)
# ## End(Not run)

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