Email discussion lists for the UK Education and Research communities

## BUGS@JISCMAIL.AC.UK

#### View:

 Message: [ First | Previous | Next | Last ] By Topic: [ First | Previous | Next | Last ] By Author: [ First | Previous | Next | Last ] Font: Proportional Font
 LISTSERV Archives BUGS Home BUGS 2006

#### Options

Subject:

multilevel binary model

From:

Date:

Sat, 21 Jan 2006 21:07:31 -0500

Content-Type:

text/plain

Parts/Attachments:

 text/plain (104 lines)
 ```Hey, Sorry for bothering everyone. I used WINBUGS to estimate a multilevel binary model using a data set which I generated a in SAS, and repeated this procedure 500 times. But the averaged results were not very good. Is there any one who also interested in this question or have some suggestions on that? I really really appreciate! Best wishes, Tianji Cai SAS code for data generation %let beta0=0.5; %let beta1=1; %let beta2=3; %let beta3=-4; %let sigma1=.25; *specify constans for simulation; %let times=1; %let seed=1257877; %let npair=200; %let nind=10; data _temp; do i=1 to &npair; u=rannor(&seed)*sqrt(&sigma1); do j=1 to &nind; x1=ranuni(&seed); x2=ranuni(&seed); x3=ranuni(&seed); p=exp(&beta0+&beta1*x1+&beta2*x2+&beta3*x3+u)/(1+exp(&beta0+&beta1*x1+&beta2*x2+&beta3*x3+u)); y=ranbin(&seed,1,p); output; end; end; run; WINBUGS code for estimation model { for( i in 1 : 200 ) {                    mu[i] ~ dnorm (0.0,tau) for( j in 1 : 10 ) {                   y[i,j] ~ dbin(k[i,j],1) logit(k[i,j]) <- beta0 + beta1*x1[i,j]+ beta2*x2[i,j]+ beta3*x3[i,j]+mu[i] }                    }           beta0 ~ dflat()           beta1 ~ dflat()           beta2 ~ dflat()           beta3 ~ dflat()           tau~ dgamma(0.001,0.001) sigma <- 1 / sqrt(tau) } list(beta0 = 1,beta1 = 0,beta2 = 1,beta3 = 2, mu=c(0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9), tau = 1) Results The MEANS Procedure Variable N Mean Std Dev Minimum Maximum ??????????????????????????????????????????????????????????????????????????????? beta0 500 0.4783718 0.1726851 -0.0317700 0.9595000 beta1 500 0.8635372 0.1912628 0.0253100 1.3260000 beta2 500 2.5657540 0.2033581 1.8820000 3.2020000 beta3 500 -3.4349880 0.2178086 -4.1460000 -2.8360000 sigma 500 0.5715244 0.1049929 0.1909000 0.8254000 sd_beta0 500 0.0938734 0.0116369 0.0803800 0.1916000 sd_beta1 500 0.1907900 0.0057146 0.1726000 0.2082000 sd_beta2 500 0.2036386 0.0069660 0.1822000 0.2268000 sd_beta3 500 0.2138558 0.0081562 0.1931000 0.2429000 sd_sigma 500 0.0938734 0.0116369 0.0803800 0.1916000 ??????????????????????????????????????????????????????????????????????????????? ------------------------------------------------------------------- This list is for discussion of modelling issues and the BUGS software. For help with crashes and error messages, first mail [log in to unmask] To mail the BUGS list, mail to [log in to unmask] Before mailing, please check the archive at www.jiscmail.ac.uk/lists/bugs.html Please do not mail attachments to the list. To leave the BUGS list, send LEAVE BUGS to [log in to unmask] If this fails, mail [log in to unmask], NOT the whole list ```