Entering edit mode
Marcin
▴
10
@marcin-3415
Last seen 9.8 years ago
Hi,
here is a source code that allows estimate interactions for Conjoint
Analysis in R. Obtained matrix xInteractions can be applied as input
in partutilities (part-worth utility estimation) or others that can be
obtained from: http://keii.ae.jgora.pl/nauka/procedury.zip.
subsets <- function(n, r) {
if(is.numeric(n) & length(n) == 1) v <- 1:n else {
v <- n
n <- length(v)
}
subs <- function(n, r, v)
if(r <= 0) NULL else
if(r >= n) matrix(v[1:n], nrow = 1) else
rbind(cbind(v[1], subs(n - 1, r - 1, v[-1])),
subs(n - 1, r , v[-1]))
subs(n, r, v)
}
# function subsets by:
# Bill Venables
# CSIRO Laboratories
# PO Box 120, Cleveland, 4163
# AUSTRALIA
interval<-function(x,begins){
output<-length(begins)
for(i in 1:(length(begins)-1)){
if((begins[i]<=x) && (x<begins[i+1])){ output<-i="" }="" }="" output="" }="" allowed="" <-function(indexes,begins){="" resul<-true="" for(i="" in="" 1:(length(indexes)-1))="" for(j="" in="" (i+1):length(indexes)){="" if(interval(indexes[i],begins)="=interval(indexes[j],begins))resul<-F" alse="" }="" resul="" }="" x<-as.matrix(x)="" numvariables<-ncol(x)="" interlevels<-2="" maxcomb<-interlevels+1="" levels<-c(2,1,1)="" begins<-seq(along.with="levels)" begins[1]<-1="" for(i="" in="" 2:length(levels)){="" begins[i]<-begins[i-1]+levels[i-1]="" }="" xinterakcje<-x="" for(i="" in="" 1:interlevels){="" for(j="" in="" 1:nrow(subsets(numvariables,i+1))){="" indexes<-subsets(numvariables,i+1)[j,]="" print(paste(paste(indexes,collapse="," ),allowed(indexes,begins)))="" if(allowed(indexes,begins)){="" output<-x[,indexes[1]]="" for(k="" in="" 2:(i+1)){="" output<-output*x[,indexes[k]]="" }="" xinterakcje<-cbind(xinterakcje,output)="" }="" }="" }="" nam<-paste("x",1:numvariables,sep="" )="" for(i="" in="" 1:interlevels){="" for(j="" in="" 1:nrow(subsets(numvariables,i+1))){="" indexes<-subsets(numvariables,i+1)[j,]="" if(allowed(indexes,begins)){="" nam<-c(nam,paste(paste("x",indexes,sep="" ),collapse="_" ))="" }="" }="" }="" colnames(xinterakcje)<-nam="" print(xinterakcje)="" x<-as.data.frame(xinterakcje)="" best="" regards,="" marcin="" [[alternative="" html="" version="" deleted]]="" <="" div="">
