## Three Parameter Logistic IRT Model
thpl.bug
thpl.dat
thpl_script
##################
library(R2WinBUGS)
Y <- as.matrix(read.table("
c:/Bugs/3plm/thpl.dat"))
n <- nrow(Y)
p <- ncol(Y)
m.alpha <- 1.0
s.alpha <- 1.0
m.delta <- 0.0
s.delta <- 1.0
a.eta <- 1.0
b.eta <- 1.0
guess.ind <- c(0, 0, 0, 0, 1, 1, 1, 1, 1, 1)
data <- list("Y", "n", "p", "guess.ind",
"m.alpha", "s.alpha",
"m.delta", "s.delta",
"a.eta", "b.eta")
parameters<- c("alpha", "delta", "theta", "eta")
thpl.sim <- bugs(data, inits=NULL, parameters.to.save=parameters,"thpl.bug",n.chains=1,
n.thin=1,n.iter=6500,n.burnin=4000,debug=TRUE,DIC=TRUE,
bugs.directory="d:/WinBUGS14/",
working.directory = "c:/Bugs/3plm")
print(thpl.sim)
########result
Inference for Bugs model at "thpl.bug", fit using WinBUGS,
1 chains, each with 6500 iterations (first 4000 discarded)
n.sims = 2500 iterations saved
mean sd 2.5% 25% 50% 75% 97.5%
alpha[1] 0.3 0.2 0.0 0.1 0.2 0.4 0.7
alpha[2] 0.5 0.1 0.2 0.4 0.5 0.6 0.8
alpha[3] 0.4 0.2 0.1 0.3 0.4 0.6 0.9
alpha[4] 0.8 0.2 0.4 0.6 0.8 0.9 1.3
alpha[5] 1.1 0.9 0.1 0.3 0.9 1.7 3.0
alpha[6] 0.6 0.6 0.0 0.2 0.4 0.8 2.1
alpha[7] 0.7 0.3 0.2 0.5 0.6 0.8 1.4
alpha[8] 0.3 0.2 0.0 0.1 0.3 0.5 0.9
alpha[9] 0.0 0.0 0.0 0.0 0.0 0.1 0.1
alpha[10] 0.3 0.3 0.0 0.0 0.2 0.5 1.0
delta[1] -0.2 0.7 -1.6 -0.6 -0.2 0.2 1.3
delta[2] -2.0 0.5 -3.1 -2.3 -1.9 -1.6 -1.0
delta[3] -0.4 0.5 -1.5 -0.7 -0.4 -0.2 0.6
delta[4] -1.7 0.4 -2.7 -2.0 -1.7 -1.4 -1.0
delta[5] 2.3 0.3 1.9 2.0 2.1 2.6 2.7
delta[6] 1.2 0.1 1.0 1.1 1.2 1.3 1.3
delta[7] 0.4 0.2 -0.1 0.2 0.5 0.6 0.7
delta[8] 0.1 0.1 -0.1 0.0 0.1 0.2 0.3
delta[9] -1.1 0.2 -1.5 -1.2 -1.1 -1.0 -0.9
delta[10] -0.1 0.4 -0.8 -0.4 0.0 0.2 0.5
theta[1] 2.1 0.2 1.6 1.9 2.1 2.3 2.4
theta[2] 0.1 0.2 -0.4 0.0 0.1 0.3 0.5
theta[3] -0.7 0.1 -0.9 -0.8 -0.7 -0.6 -0.4
theta[4] 0.2 0.1 -0.2 0.1 0.2 0.3 0.4
theta[5] -0.5 0.2 -0.8 -0.7 -0.6 -0.4 -0.2
theta[6] -1.5 0.1 -1.7 -1.6 -1.5 -1.4 -1.2
theta[7] -1.0 0.3 -1.4 -1.2 -1.0 -0.9 -0.4
theta[8] -1.6 0.4 -2.1 -2.0 -1.7 -1.3 -1.1
theta[9] -0.7 0.3 -1.1 -0.9 -0.7 -0.5 -0.2
theta[10] 1.5 0.2 1.2 1.4 1.5 1.6 1.8
theta[11] -0.4 0.1 -0.7 -0.5 -0.4 -0.3 -0.2
theta[12] -0.6 0.2 -0.9 -0.7 -0.6 -0.5 -0.3
theta[13] 2.3 0.1 2.0 2.2 2.3 2.4 2.6
theta[14] 0.6 0.3 0.2 0.3 0.6 1.0 1.1
theta[15] -1.3 0.2 -1.6 -1.5 -1.4 -1.1 -0.8
theta[16] -0.7 0.2 -1.1 -0.9 -0.7 -0.6 -0.3
theta[17] 0.0 0.2 -0.3 -0.2 0.0 0.1 0.3
theta[18] -0.3 0.1 -0.5 -0.4 -0.3 -0.3 -0.1
theta[19] -0.4 0.3 -0.9 -0.6 -0.3 -0.2 0.0
theta[20] 0.9 0.1 0.7 0.8 0.9 1.0 1.1
theta[21] -1.7 0.2 -2.0 -1.8 -1.7 -1.6 -1.3
theta[22] 1.9 0.2 1.4 1.6 1.9 2.0 2.2
theta[23] 0.6 0.2 0.3 0.5 0.5 0.7 1.0
theta[24] 1.0 0.1 0.8 1.0 1.1 1.1 1.2
theta[25] -0.4 0.2 -0.7 -0.6 -0.3 -0.2 0.1
theta[26] -0.6 0.2 -0.9 -0.7 -0.7 -0.5 -0.2
theta[27] -1.3 0.1 -1.5 -1.3 -1.3 -1.2 -1.1
theta[28] 1.1 0.1 0.8 0.9 1.1 1.2 1.3
theta[29] 0.4 0.2 0.1 0.2 0.4 0.6 0.8
theta[30] 0.5 0.4 -0.1 0.2 0.3 0.9 1.2
theta[31] 0.5 0.2 0.2 0.3 0.5 0.6 0.8
theta[32] 0.8 0.1 0.6 0.7 0.8 0.9 1.1
theta[33] -0.4 0.1 -0.5 -0.5 -0.4 -0.3 -0.1
theta[34] -0.4 0.2 -0.8 -0.6 -0.5 -0.2 0.0
theta[35] 0.9 0.2 0.6 0.7 0.9 1.1 1.2
theta[36] 2.1 0.2 1.7 2.0 2.1 2.3 2.5
theta[37] 0.8 0.1 0.6 0.7 0.8 1.0 1.1
theta[38] -1.4 0.2 -1.8 -1.6 -1.4 -1.2 -1.0
theta[39] -0.6 0.1 -0.8 -0.7 -0.6 -0.6 -0.4
theta[40] -0.9 0.1 -1.1 -1.0 -0.9 -0.8 -0.7
theta[41] -0.6 0.2 -0.9 -0.8 -0.5 -0.4 -0.3
theta[42] -0.5 0.1 -0.7 -0.6 -0.5 -0.4 -0.2
theta[43] 1.1 0.2 0.9 1.0 1.1 1.3 1.4
theta[44] -1.0 0.1 -1.3 -1.1 -1.0 -0.9 -0.8
theta[45] 1.3 0.2 0.9 1.2 1.3 1.4 1.5
theta[46] 0.2 0.1 -0.1 0.2 0.2 0.3 0.5
theta[47] -0.5 0.2 -0.8 -0.6 -0.5 -0.4 -0.1
theta[48] -1.1 0.1 -1.3 -1.2 -1.1 -1.0 -0.9
theta[49] -0.2 0.2 -0.5 -0.4 -0.2 -0.1 0.0
theta[50] -0.5 0.1 -0.8 -0.6 -0.6 -0.4 -0.3
theta[51] -0.7 0.1 -0.9 -0.8 -0.7 -0.6 -0.4
theta[52] -0.4 0.1 -0.7 -0.5 -0.4 -0.3 -0.2
theta[53] -0.2 0.1 -0.4 -0.3 -0.2 -0.2 -0.1
theta[54] -0.5 0.1 -0.8 -0.6 -0.5 -0.4 -0.3
theta[55] 0.5 0.2 0.2 0.4 0.5 0.7 0.9
theta[56] -0.3 0.2 -0.5 -0.4 -0.3 -0.1 0.1
theta[57] -0.3 0.2 -0.6 -0.4 -0.2 -0.1 0.1
theta[58] -0.3 0.1 -0.5 -0.3 -0.3 -0.2 -0.1
theta[59] -0.7 0.2 -1.0 -0.9 -0.8 -0.6 -0.4
theta[60] 0.6 0.1 0.4 0.5 0.6 0.8 0.9
theta[61] 0.4 0.2 0.0 0.2 0.4 0.6 0.8
theta[62] 0.1 0.3 -0.4 -0.2 -0.1 0.4 0.6
theta[63] -0.1 0.3 -0.6 -0.4 -0.1 0.0 0.2
theta[64] -1.8 0.1 -2.0 -1.9 -1.8 -1.7 -1.6
theta[65] 2.3 0.3 1.8 2.0 2.4 2.6 2.8
theta[66] -0.5 0.1 -0.6 -0.5 -0.5 -0.4 -0.3
theta[67] 0.0 0.2 -0.2 -0.1 0.0 0.1 0.3
theta[68] -0.1 0.2 -0.5 -0.3 0.0 0.1 0.3
theta[69] -2.0 0.2 -2.3 -2.1 -2.0 -1.8 -1.7
theta[70] -0.3 0.1 -0.6 -0.4 -0.3 -0.2 0.0
theta[71] -1.4 0.3 -1.9 -1.7 -1.4 -1.0 -0.9
theta[72] 1.6 0.3 1.1 1.4 1.7 1.9 2.0
theta[73] 0.7 0.1 0.5 0.6 0.7 0.8 1.1
theta[74] 0.5 0.2 0.2 0.3 0.4 0.5 0.9
theta[75] -0.8 0.1 -1.0 -0.9 -0.8 -0.7 -0.6
theta[76] 0.6 0.2 0.1 0.5 0.7 0.8 1.0
theta[77] 0.7 0.1 0.5 0.6 0.6 0.8 1.0
theta[78] 0.9 0.2 0.7 0.8 0.9 1.0 1.2
theta[79] -0.1 0.2 -0.4 -0.2 0.0 0.1 0.2
theta[80] -0.8 0.2 -1.2 -1.1 -0.8 -0.6 -0.4
theta[81] -1.1 0.1 -1.4 -1.2 -1.1 -1.0 -0.9
theta[82] -0.7 0.1 -1.0 -0.8 -0.7 -0.6 -0.5
theta[83] 1.6 0.2 1.2 1.5 1.6 1.8 2.0
theta[84] -0.1 0.3 -0.5 -0.4 0.0 0.1 0.3
theta[85] 0.4 0.5 -0.4 0.0 0.3 0.9 1.1
theta[86] -0.5 0.2 -0.8 -0.7 -0.6 -0.3 -0.1
theta[87] -0.9 0.2 -1.3 -1.1 -0.8 -0.7 -0.6
theta[88] -0.2 0.2 -0.6 -0.3 -0.2 0.0 0.2
theta[89] 0.7 0.2 0.2 0.6 0.7 0.9 1.0
theta[90] 0.1 0.4 -0.7 -0.1 0.2 0.5 0.9
theta[91] -0.5 0.1 -0.7 -0.6 -0.5 -0.4 -0.2
theta[92] 1.3 0.2 1.0 1.1 1.3 1.4 1.7
theta[93] -1.6 0.4 -2.0 -1.9 -1.7 -1.1 -0.8
theta[94] -0.8 0.3 -1.4 -1.1 -0.7 -0.5 -0.4
theta[95] -0.4 0.1 -0.6 -0.5 -0.4 -0.3 -0.1
theta[96] 0.4 0.3 -0.1 0.1 0.3 0.5 1.0
theta[97] -0.4 0.2 -0.7 -0.5 -0.4 -0.3 -0.1
theta[98] -1.5 0.2 -1.7 -1.6 -1.5 -1.3 -1.1
theta[99] -0.4 0.2 -0.9 -0.5 -0.4 -0.2 -0.1
theta[100] 0.0 0.2 -0.3 -0.2 0.0 0.1 0.3
eta[5] 0.3 0.1 0.0 0.1 0.3 0.4 0.5
eta[6] 0.5 0.1 0.3 0.4 0.5 0.6 0.7
eta[7] 0.1 0.1 0.0 0.0 0.1 0.1 0.2
eta[8] 0.2 0.1 0.0 0.1 0.2 0.3 0.4
eta[9] 0.0 0.0 0.0 0.0 0.0 0.0 0.1
eta[10] 0.0 0.0 0.0 0.0 0.0 0.0 0.1
deviance 1323.8 10.4 1300.0 1318.0 1325.0 1331.0 1342.0
DIC info (using the rule, pD = Dbar-Dhat)
pD = 2.8 and DIC = 1326.6
DIC is an estimate of expected predictive error (lower deviance is better).