函数 mixed.model.B (GAMM)

Question

有没有人用过这个功能

"mixed.model.B"

？如果是，我可以找到哪个包？

这个在data.zip段，数据是leukemia.txt。注意：我正在使用指定的库：

library(nlme)
library(ggplot2)
library(GGally)
library(splines)
library(nlme)
library(fields)
library(lattice)
require(ISLR)
library(grid)
library(dplyr)
library(MASS)
library(mgcv)
library(latticeExtra)
library(fields)

查看下面的代码：

attach(leukemia)
X=model.matrix(height~factor(treatment)*age)
treatment=factor(treatment)

MM=mixed.model.B(age,min(age)-0.5,max(age)+0.5,40,3,2,type="Eilers")

 Z=MM[[2]]

Id=factor(rep(1,length(height)))

Z.block4=list(treatment=pdIdent(~Z-1),case=pdSymm(~age))

data.fr <- groupedData(height ~ X[,-1] | Id, data = data.frame(height,X,Z,case,age))
model4 <- lme(height~X[,-1],data=data.fr,random=Z.block4) 

## Fitted individual trends for the smooth random intercept and slope model by treatment

b4 <- xyplot(fitted(fit4.gamm$lme) ~ age|factor(treatment),groups=case,col=tim.colors(length(unique(leukemia$case))),
       lwd=1,pch=19,data=leukemia,main="Treatment",cex=.35,type="a")
a2 + as.layer(b4)

Answer 1

在您列出的 link 中，有一个 link 下载 R 文件： http://halweb.uc3m.es/esp/Personal/personas/durban/esp/web/cursos/Maringa/gam-markdown/Gams-code.R

第349行，作者构建函数，我复制如下：

# Mixed model representation of B-splines (using svd)
mixed.model.B<-function(x,xl,xr,ndx,bdeg,pord,type="Eilers"){
  Bbasis=bspline(x,xl,xr,ndx,bdeg)
  B <- Bbasis$B
  m=ncol(B)
  D=diff(diag(m),differences=pord)

  if(type=="Eilers"){
  Z <- B%*%t(D)%*%solve(D%*%t(D))
  }else if(type=="SVD"){ print("SVD method")
  P.svd=svd(t(D)%*%D)
  U=(P.svd$u)[,1:(m-pord)]
  d=(P.svd$d)[1:(m-pord)]
  Delta=diag(1/sqrt(d))
  Z=B%*%U%*%Delta
  }
  X=NULL
    for(i in 0:(pord-1)){
        X=cbind(X,x^i)
        }
  output <- list(X=X,Z=Z)
  return(output)
}

函数 mixed.model.B (GAMM)

function mixed.model.B (GAMM)

statistics

r

gam

mixed-models