Displaying 1 result from an estimated 1 matches for "sce_yest".
2005 Apr 01
1
optim problem, nls regression
...-c(0,8,21,35)
Hence, the sum of squares is:
Sce= sum( sum((y- number[4]-(x/number[1])^number[7])^2)+
sum((y- number[5]-(x/number[2])^number[7])^2)+
sum((y- number[6]-(x/number[3])^number[7])^2)+
for minimising this sum, I compute the function "sce":
sce<-function(param){
sce_yest<-matrix(nrow=3,ncol=1)
for( i in 1:3){
yy<-(y[((long[i]+1):long[i+1])])
xx<-x[(long[i]+1):(long[i+1])]
y_est<-(param[i+2]-(xx/param[i])^param[(2*3)+1])
sce_yest[i,]<-sum((yy-y_est)^2)
}
return(sum(sce_yest))
}
Then, I use the fonction optim for obtaining a vector of 7 paramete...