Hi, I wonder if anyone can help me with this issue. I am using R2BayesX. It seems that the model can maximally contain 20 interactions. When the number of interaction terms exceed 20, the code stops working. Here is a piece of toy code. rm(list=ls()) library(BayesX) library(R2BayesX) #data generating model f2<-function(x1,x2,x3,x4) { y<-2*sin(pi*x1)*1.5+exp(2*x2)/3+2 * sin(4 * pi * (x3 - 0.2) *(x4 - 0.7)) } #the dataset nsample<-40 #sample size x1.tot<-runif(nsample,0,1) x2.tot<-runif(nsample,0,1) x3.tot<-runif(nsample,0,1) x4.tot<-runif(nsample,0,1) x5.tot<-runif(nsample,0,1) x6.tot<-runif(nsample,0,1) x7.tot<-runif(nsample,0,1) pnoise<-0.2 eta<-f2(x1.tot,x2.tot,x3.tot,x4.tot) y.tot<-eta+pnoise*rnorm(nsample,0,1) d<-data.frame(y.tot,x1.tot,x2.tot,x3.tot,x4.tot,x5.tot,x6.tot,x7.tot) nk2<-5 # the full model that contains the interactions of all pairs of x1~x7, 21 terms in total fr2<-y.tot ~ sx(x1.tot, x2.tot, knots = nk2, bs = "te") + sx(x1.tot, x3.tot, knots = nk2, bs = "te") + sx(x1.tot, x4.tot, knots = nk2, bs = "te") + sx(x1.tot, x5.tot, knots nk2, bs = "te") + sx(x1.tot, x6.tot, knots = nk2, bs = "te") + sx(x1.tot, x7.tot, knots nk2, bs = "te") + sx(x2.tot, x3.tot, knots = nk2, bs = "te") + sx(x2.tot, x4.tot, knots nk2, bs = "te") + sx(x2.tot, x5.tot, knots = nk2, bs = "te") + sx(x2.tot, x6.tot, knots nk2, bs = "te") + sx(x2.tot, x7.tot, knots = nk2, bs = "te") + sx(x3.tot, x4.tot, knots nk2, bs = "te") + sx(x3.tot, x5.tot, knots = nk2, bs = "te") + sx(x3.tot, x6.tot, knots nk2, bs = "te") + sx(x3.tot, x7.tot, knots = nk2, bs = "te") + sx(x4.tot, x5.tot, knots nk2, bs = "te") + sx(x4.tot, x6.tot, knots = nk2, bs = "te") + sx(x4.tot, x7.tot, knots nk2, bs = "te") + sx(x5.tot, x6.tot, knots = nk2, bs = "te") + sx(x5.tot, x7.tot, knots nk2, bs = "te") + sx(x6.tot, x7.tot, knots = nk2, bs = "te") m2<-bayesx(fr2,data = d) The code halted in a couple of seconds after the last function, with a warning: Warning message: running command '"C:/Users/Hairong/Documents/R/win-library/3.2/BayesXsrc/libs/x64/BayesX.exe" C:/Users/Hairong/AppData/Local/Temp/RtmpkFfoCH/bayesx5/bayesx.estim.input.prg' had status 5 The model was not estimated. However, if I delete ANY one of the interaction terms to make the total interaction terms 20, the model can be estimated. I would appreciate your suggestion and explanation on this problem. Thank you a lot. Hairong [[alternative HTML version deleted]]