summary(BEPS)
  
if (require(splines) && require(nnet)){ # for bs() and multinom()
  beps <- multinom(vote ~ age + gender + economic.cond.national + economic.cond.household 
  	+ Blair + Hague + Kennedy + bs(Europe, 3)*political.knowledge, data=BEPS)
  europe.knowledge <- effect("bs(Europe, 3)*political.knowledge", beps, 
  	xlevels=list(Europe=seq(1, 11, length=50), political.knowledge=0:3),
    	given.values=c(gendermale=0.5))
  plot(europe.knowledge)
  plot(europe.knowledge, style="stacked", colors=c("blue", "red", "orange"), rug=FALSE)
}
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