aft.R
nsxD <-
function (x, df = NULL, knots = NULL, intercept = FALSE, Boundary.knots = range(x),
derivs = if (cure) c(2, 1) else c(2, 2), log = FALSE, centre = FALSE,
cure = FALSE, stata.stpm2.compatible = FALSE)
{
nx <- names(x)
x <- as.vector(x)
nax <- is.na(x)
if (nas <- any(nax))
x <- x[!nax]
if (!missing(Boundary.knots)) {
Boundary.knots <- sort(Boundary.knots)
outside <- (ol <- x < Boundary.knots[1L]) | (or <- x >
Boundary.knots[2L])
}
else outside <- FALSE
if (!missing(df) && missing(knots)) {
nIknots <- df - 1 - intercept + 4 - sum(derivs)
if (nIknots < 0) {
nIknots <- 0
warning("'df' was too small; have used ", 1 + intercept)
}
knots <- if (nIknots > 0) {
knots <- if (!cure)
seq.int(0, 1, length.out = nIknots + 2L)[-c(1L,
nIknots + 2L)]
else c(seq.int(0, 1, length.out = nIknots + 1L)[-c(1L,
nIknots + 1L)], 0.95)
if (!stata.stpm2.compatible)
stats::quantile(x[!outside], knots)
else stats::quantile(x[!outside], round(knots, 2),
type = 2)
}
}
else nIknots <- length(knots)
Aknots <- sort(c(rep(Boundary.knots, 4L), knots))
if (any(outside)) {
basis <- array(0, c(length(x), nIknots + 4L))
if (any(ol)) {
k.pivot <- Boundary.knots[1L]
tt <- spline.des(Aknots, rep(k.pivot, sum(ol)), 4, 1)$design
basis[ol, ] <- tt
}
if (any(or)) {
k.pivot <- Boundary.knots[2L]
tt <- spline.des(Aknots, rep(k.pivot, sum(or)), 4, 1)$design
basis[or, ] <- tt
}
if (any(inside <- !outside))
basis[inside, ] <- spline.des(Aknots, x[inside],
4, 1)$design
}
else basis <- spline.des(Aknots, x, 4, 1)$design
const <- splineDesign(Aknots, rep(Boundary.knots, 3 - derivs),
4, c(derivs[1]:2, derivs[2]:2))
if (!intercept) {
const <- const[, -1, drop = FALSE]
basis <- basis[, -1, drop = FALSE]
}
qr.const <- qr(t(const))
q.const <- qr.Q(qr.const, complete=TRUE)[, -(1L:2L), drop = FALSE] # NEW
basis <- as.matrix((t(qr.qty(qr.const, t(basis))))[, -(1L:nrow(const)),
drop = FALSE])
n.col <- ncol(basis)
if (nas) {
nmat <- matrix(NA, length(nax), n.col)
nmat[!nax, ] <- basis
basis <- nmat
}
dimnames(basis) <- list(nx, 1L:n.col)
if (centre) {
centreBasis <- nsx(centre, knots = if (is.null(knots))
numeric(0)
else knots, Boundary.knots = Boundary.knots, intercept = intercept,
derivs = derivs, centre = FALSE, log = log)
oldAttributes <- attributes(basis)
basis <- t(apply(basis, 1, function(x) x - centreBasis))
attributes(basis) <- oldAttributes
}
a <- list(degree = 3, knots = if (is.null(knots)) numeric(0) else knots,
Boundary.knots = Boundary.knots, intercept = intercept,
derivs = derivs, centre = centre, log = log, q.const = q.const)
attributes(basis) <- c(attributes(basis), a)
class(basis) <- c("nsxD", "basis", "matrix")
basis
}
makepredictcall.nsxD <-
function (var, call)
{
if (as.character(call)[1L] != "nsxD")
return(call)
at <- attributes(var)[c("knots", "Boundary.knots", "intercept",
"derivs", "centre", "log")]
xxx <- call[1L:2]
xxx[names(at)] <- at
xxx
}
predict.nsxD <-
function (object, newx, ...)
{
if (missing(newx))
return(object)
a <- c(list(x = newx), attributes(object)[c("knots", "Boundary.knots",
"intercept", "derivs", "centre", "log")])
do.call("nsxD", a)
}
nsxDD <-
function (x, df = NULL, knots = NULL, intercept = FALSE, Boundary.knots = range(x),
derivs = if (cure) c(2, 1) else c(2, 2), log = FALSE, centre = FALSE,
cure = FALSE, stata.stpm2.compatible = FALSE)
{
nx <- names(x)
x <- as.vector(x)
nax <- is.na(x)
if (nas <- any(nax))
x <- x[!nax]
if (!missing(Boundary.knots)) {
Boundary.knots <- sort(Boundary.knots)
outside <- (ol <- x < Boundary.knots[1L]) | (or <- x >
Boundary.knots[2L])
}
else outside <- FALSE
if (!missing(df) && missing(knots)) {
nIknots <- df - 1 - intercept + 4 - sum(derivs)
if (nIknots < 0) {
nIknots <- 0
warning("'df' was too small; have used ", 1 + intercept)
}
knots <- if (nIknots > 0) {
knots <- if (!cure)
seq.int(0, 1, length.out = nIknots + 2L)[-c(1L,
nIknots + 2L)]
else c(seq.int(0, 1, length.out = nIknots + 1L)[-c(1L,
nIknots + 1L)], 0.95)
if (!stata.stpm2.compatible)
stats::quantile(x[!outside], knots)
else stats::quantile(x[!outside], round(knots, 2),
type = 2)
}
}
else nIknots <- length(knots)
Aknots <- sort(c(rep(Boundary.knots, 4L), knots))
if (any(outside)) {
basis <- array(0, c(length(x), nIknots + 4L))
if (any(ol)) {
basis[ol, ] <- 0
}
if (any(or)) {
basis[or, ] <- 0
}
if (any(inside <- !outside))
basis[inside, ] <- spline.des(Aknots, x[inside],
4, 2)$design
}
else basis <- spline.des(Aknots, x, 4, 2)$design
const <- splineDesign(Aknots, rep(Boundary.knots, 3 - derivs),
4, c(derivs[1]:2, derivs[2]:2))
if (!intercept) {
const <- const[, -1, drop = FALSE]
basis <- basis[, -1, drop = FALSE]
}
qr.const <- qr(t(const))
q.const <- qr.Q(qr.const, complete=TRUE)[, -(1L:2L), drop = FALSE] # NEW
basis <- as.matrix((t(qr.qty(qr.const, t(basis))))[, -(1L:nrow(const)),
drop = FALSE])
n.col <- ncol(basis)
if (nas) {
nmat <- matrix(NA, length(nax), n.col)
nmat[!nax, ] <- basis
basis <- nmat
}
dimnames(basis) <- list(nx, 1L:n.col)
if (centre) {
centreBasis <- nsx(centre, knots = if (is.null(knots))
numeric(0)
else knots, Boundary.knots = Boundary.knots, intercept = intercept,
derivs = derivs, centre = FALSE, log = log)
oldAttributes <- attributes(basis)
basis <- t(apply(basis, 1, function(x) x - centreBasis))
attributes(basis) <- oldAttributes
}
a <- list(degree = 3, knots = if (is.null(knots)) numeric(0) else knots,
Boundary.knots = Boundary.knots, intercept = intercept,
derivs = derivs, centre = centre, log = log, q.const = q.const)
attributes(basis) <- c(attributes(basis), a)
class(basis) <- c("nsxDD", "basis", "matrix")
basis
}
makepredictcall.nsxDD <-
function (var, call)
{
if (as.character(call)[1L] != "nsxDD")
return(call)
at <- attributes(var)[c("knots", "Boundary.knots", "intercept",
"derivs", "centre", "log")]
xxx <- call[1L:2]
xxx[names(at)] <- at
xxx
}
predict.nsxDD <-
function (object, newx, ...)
{
if (missing(newx))
return(object)
a <- c(list(x = newx), attributes(object)[c("knots", "Boundary.knots",
"intercept", "derivs", "centre", "log")])
do.call("nsxDD", a)
}
## test nsxD and nsxDD
if (FALSE) {
zeros <- function(mat,rows=1:nrow(mat),cols=1:ncol(mat)) "[<-"(mat,rows,cols,0)
tm <- as.numeric(3:5)
tm2 <- as.numeric(0:11)
y <- rnorm(length(tm))
lm1 <- lm(y~nsx(tm,df=4))
lmD1 <- lm(y~nsxD(tm,df=4)-1)
lmDD1 <- lm(y~nsxDD(tm,df=4)-1)
eps <- 1e-5
(lpmatrix.lm(lm1,newdata=data.frame(tm=tm2+eps)) -
lpmatrix.lm(lm1,newdata=data.frame(tm=tm2-eps)))/(2*eps) -
cbind(0,lpmatrix.lm(lmD1,newdata=data.frame(tm=tm2))) # ok
(lpmatrix.lm(lmD1,newdata=data.frame(tm=tm2+eps)) -
lpmatrix.lm(lmD1,newdata=data.frame(tm=tm2-eps)))/(2*eps) -
lpmatrix.lm(lmDD1,newdata=data.frame(tm=tm2)) # ok
}
S0hat <- function(obj)
{
## predicted survival for individuals (adjusted for covariates)
newobj = survfit(obj,se.fit=FALSE)
surv = newobj$surv
surv[match(obj$y[,ncol(obj$y)-1],newobj$time)]
}
## general link functions
setClass("aft", representation(args="list"), contains="mle2")
aft <- function(formula, data, smooth.formula = NULL, df = 3,
control = list(parscale = 1, maxit = 1000), init = NULL,
weights = NULL,
timeVar = "", time0Var = "",
reltol=1.0e-8, trace = 0,
contrasts = NULL, subset = NULL, use.gr = TRUE, ...) {
## parse the event expression
eventInstance <- eval(lhs(formula),envir=data)
stopifnot(length(lhs(formula))>=2)
eventExpr <- lhs(formula)[[length(lhs(formula))]]
delayed <- length(lhs(formula))>=4 # indicator for multiple times (cf. strictly delayed)
surv.type <- attr(eventInstance,"type")
if (surv.type %in% c("interval","interval2","left","mstate"))
stop("stpm2 not implemented for Surv type ",surv.type,".")
counting <- attr(eventInstance,"type") == "counting"
## interval <- attr(eventInstance,"type") == "interval"
timeExpr <- lhs(formula)[[if (delayed) 3 else 2]] # expression
if (timeVar == "")
timeVar <- all.vars(timeExpr)
## set up the formulae
full.formula <- formula
if (!is.null(smooth.formula))
rhs(full.formula) <- rhs(formula) %call+% rhs(smooth.formula)
rhs(full.formula) <- rhs(full.formula) %call+% quote(0)
##
## set up the data
## ensure that data is a data frame
## data <- get_all_vars(full.formula, data) # but this loses the other design information
## restrict to non-missing data (assumes na.action=na.omit)
.include <- apply(model.matrix(formula, data, na.action = na.pass), 1, function(row) !any(is.na(row))) &
!is.na(eval(eventExpr,data)) & !is.na(eval(timeExpr,data))
data <- data[.include, , drop=FALSE]
##
## parse the function call
Call <- match.call()
mf <- match.call(expand.dots = FALSE)
m <- match(c("formula", "data", "subset", "contrasts", "weights"),
names(mf), 0L)
mf <- mf[c(1L, m)]
##
## get variables
time <- eval(timeExpr, data, parent.frame())
if (any(time>0 & time<1e-4))
warning("Some event times < 1e-4: consider transforming time to avoid problems with finite differences")
time0Expr <- NULL # initialise
if (delayed) {
time0Expr <- lhs(formula)[[2]]
if (time0Var == "")
time0Var <- all.vars(time0Expr)
time0 <- eval(time0Expr, data, parent.frame())
if (any(time0>0 & time0<1e-4))
warning("Some entry times < 1e-4: consider transforming time to avoid problems with finite differences")
} else {
time0 <- NULL
}
event <- eval(eventExpr,data)
## if all the events are the same, we assume that they are all events, else events are those greater than min(event)
event <- if (length(unique(event))==1) rep(TRUE, length(event)) else event <- event > min(event)
## setup for initial values
## Cox regression
coxph.call <- mf
coxph.call[[1L]] <- as.name("coxph")
coxph.call$model <- TRUE
coxph.obj <- eval(coxph.call, envir=parent.frame())
y <- model.extract(model.frame(coxph.obj),"response")
data$logHhat <- pmax(-18,log(-log(S0hat(coxph.obj))))
##
## Weibull regression
if (delayed) {
if (requireNamespace("eha", quietly = TRUE)) {
survreg1 <- eha::aftreg(formula, data)
coef1 <- coef(survreg1)
coef1 <- coef1[1:(length(coef1)-2)]
} else coef1 <- rep(0,ncol(X))
} else {
survreg1 <- survival::survreg(formula, data)
coef1 <- coef(survreg1)
coef1 <- coef1[-1] # assumes intercept included in the formula; ignores smooth.formula
}
## pred1 <- predict(survreg1)
data$logtstar <- log(time)
## data$logtstar <- log(time/pred1)
## initial values and object for lpmatrix predictions
lm.call <- mf
lm.call[[1L]] <- as.name("lm")
lm.formula <- full.formula
lhs(lm.formula) <- quote(logtstar) # new response
lm.call$formula <- lm.formula
dataEvents <- data[event,]
lm.call$data <- quote(dataEvents) # events only
lm.obj <- eval(lm.call)
coef1b <- coef(lm.obj)
if (names(coef1b)[1]=="(Intercept)") coef1b <- coef1b[-1] # ???
## if (is.null(init)) {
## init <- coef(lm.obj)
## }
lm0.obj <- lm(logHhat~nsx(logtstar,df,intercept=TRUE)-1,dataEvents)
## lm0D.obj <- lm(logHhat~nsxD(logtstar,df,intercept=TRUE)-1,dataEvents)
coef0 <- coef(lm0.obj) # log-log baseline
## design information for baseline survival
design <- nsx(dataEvents$logtstar, df=df, intercept=TRUE)
designD <- nsxD(dataEvents$logtstar, df=df, intercept=TRUE)
designDD <- nsxDD(dataEvents$logtstar, df=df, intercept=TRUE)
##
## set up mf and wt
mt <- terms(lm.obj)
mf <- model.frame(lm.obj)
## wt <- model.weights(lm.obj$model)
wt <- if (is.null(substitute(weights))) rep(1,nrow(data)) else eval(substitute(weights),data,parent.frame())
##
## XD matrix
lpfunc <- function(delta,fit,dataset,var) {
dataset[[var]] <- dataset[[var]]+delta
lpmatrix.lm(fit,dataset)
}
##
## initialise values
ind0 <- FALSE
map0 <- 0L
which0 <- 0
wt0 <- 0
## ttype <- 0
## surv.type %in% c("right","counting")
X <- lpmatrix.lm(lm.obj,data)
XD <- grad(lpfunc,0,lm.obj,data,timeVar)
XD <- matrix(XD,nrow=nrow(X))
X0 <- matrix(0,1,ncol(X))
if (delayed && all(time0==0)) delayed <- FALSE # CAREFUL HERE: delayed redefined
if (delayed) {
ind0 <- time0>0
map0 <- vector("integer",nrow(X))
map0[ind0] <- as.integer(1:sum(ind0))
map0[!ind0] <- NaN
##which0 <- which(ind0)
which0 <- 1:nrow(X)
which0[!ind0] <- NaN
data0 <- data[ind0,,drop=FALSE] # data for delayed entry times
data0[[timeVar]] <- data0[[time0Var]]
X0 <- lpmatrix.lm(lm.obj, data0)
wt0 <- wt[ind0]
rm(data0)
}
if (ncol(X)>length(coef1)) {
coef1 <- c(coef1,rep(0,ncol(X) - length(coef1)))
names(coef1) <- names(coef1b)
}
init <- c(coef1,coef0)
if (!is.null(control) && "parscale" %in% names(control)) {
if (length(control$parscale)==1)
control$parscale <- rep(control$parscale,length(init))
if (is.null(names(control$parscale)))
names(control$parscale) <- names(init)
}
parscale <- rep(if (is.null(control$parscale)) 1 else control$parscale,length=length(init))
names(parscale) <- names(init)
args <- list(init=init,X=X,XD=XD,wt=wt,event=ifelse(event,1,0),time=time,y=y,
timeVar=timeVar,timeExpr=timeExpr,terms=mt,
delayed=delayed, X0=X0, wt0=wt0, parscale=parscale, reltol=reltol,
time0=if (delayed) time0[time0>0] else NULL,
trace = as.integer(trace), map0 = map0 - 1L, ind0 = ind0, which0 = which0 - 1L,
boundaryKnots=attr(design,"Boundary.knots"), q.const=t(attr(design,"q.const")),
interiorKnots=attr(design,"knots"), design=design, designD=designD,
designDD=designDD,
data=data, lm.obj = lm.obj, return_type="optim")
negll <- function(beta) {
localargs <- args
localargs$return_type <- "objective"
localargs$init <- beta
return(.Call("aft_model_output", localargs, PACKAGE="rstpm2"))
}
gradient <- function(beta) {
localargs <- args
localargs$return_type <- "gradient"
localargs$init <- beta
return(.Call("aft_model_output", localargs, PACKAGE="rstpm2"))
}
negll.slow <- function(betafull) {
beta <- betafull[1:ncol(args$X)]
betas <- betafull[-(1:ncol(args$X))]
time <- args$time
eta <- as.vector(args$X %*% beta)
etaD <- as.vector(args$XD %*% beta)
logtstar <- log(args$time) - eta
etas <- as.vector(predict(args$design,logtstar) %*% betas)
etaDs <- as.vector(predict(args$designD,logtstar) %*% betas)
## fix bounds on etaDs
eps <- etaDs*0. + 1e-8;
pen <- sum(pmin(etaDs,eps)*pmin(etaDs,eps))
etaDs <- pmax(etaDs, eps)
## fix bounds on etaD
pen = pen + sum(pmin(1/time-etaD,eps)*pmin(1/time-etaD,eps))
etaD <- 1/time - pmax(1/time-etaD, eps);
logh <- etas + log(etaDs) + log(1/time -etaD)
H <- exp(etas)
pen - (sum(logh*event) - sum(H))
}
neglli <- function(betafull) {
beta <- betafull[1:ncol(args$X)]
betas <- betafull[-(1:ncol(args$X))]
time <- args$time
eta <- as.vector(args$X %*% beta)
etaD <- as.vector(args$XD %*% beta)
logtstar <- log(args$time) - eta
etas <- as.vector(predict(args$design,logtstar) %*% betas)
etaDs <- as.vector(predict(args$designD,logtstar) %*% betas)
## fix bounds on etaDs
eps <- etaDs*0. + 1e-8;
pen <- pmin(etaDs,eps)*pmin(etaDs,eps)
etaDs <- pmax(etaDs, eps)
## fix bounds on etaD
pen <- pen + pmin(1/time-etaD,eps)*pmin(1/time-etaD,eps)
etaD <- 1/time - pmax(1/time-etaD, eps);
logh <- etas + log(etaDs) + log(1/time -etaD)
H <- exp(etas)
pen - (logh*event - H)
}
gradi <- function(betafull) {
beta <- betafull[1:ncol(args$X)]
betas <- betafull[-(1:ncol(args$X))]
time <- args$time
eta <- as.vector(args$X %*% beta)
etaD <- as.vector(args$XD %*% beta)
logtstar <- log(args$time) - eta
Xs <- predict(args$design,logtstar)
XDs <- predict(args$designD,logtstar)
XDDs <- predict(args$designDD,logtstar)
etas <- as.vector(Xs %*% betas)
etaDs <- as.vector(XDs %*% betas)
etaDDs <- as.vector(XDDs %*% betas)
## H calculations
H <- exp(etas)
dHdbetas <- H*Xs
dHdbeta <- -H*etaDs*X
## penalties
eps <- etaDs*0. + 1e-8;
pindexs <- etaDs < eps
pindex <- 1/time-etaD < eps
## fix bounds on etaDs
pgrads <- cbind(-2*etaDs*etaDDs*X,2*etaDs*XDs)
etaDs <- pmax(etaDs, eps)
## fix bounds on etaD
pgrad <- cbind(-2*(1/time-etaD)*XD,XDs*0)
etaD <- 1/time - pmax(1/time-etaD, eps)
##
logh <- etas + log(etaDs) + log(1/time -etaD)
h <- exp(logh)
dloghdbetas <- Xs+XDs/etaDs*(!pindexs)
dloghdbeta <- -etaDs*X*(!pindexs & !pindex) - etaDDs*X/etaDs*(!pindexs & !pindex) - XD/(1/time-etaD)*(!pindex & !pindexs)
dhdbetas <- h*dloghdbetas
dhdbeta <- h*dloghdbeta
cbind(-dloghdbeta*event+dHdbeta, -dloghdbetas*event+dHdbetas) + pindex*pgrad + pindexs*pgrads
}
gradient2 <- function(betafull)
colSums(gradi(betafull))
## browser()
if (FALSE) {
library(rstpm2)
##debug(aft)
brcancer2 <- transform(brcancer, entry=ifelse(hormon==0, rectime/2, 0))
system.time(aft1 <- aft(Surv(entry,rectime,censrec==1)~hormon,data=brcancer2,df=4,use.gr=FALSE))
system.time(aft0 <- aft(Surv(entry,rectime,censrec==1)~hormon,data=brcancer2,df=4))
library(rstpm2)
system.time(aft0 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4))
system.time(aft1 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4,use.gr=FALSE))
##
brcancer100 <- brcancer[rep(1:nrow(brcancer),each=100),]
system.time(aft0 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer100,df=4))
system.time(aft1 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer100,df=4,use.gr=FALSE))
## in browser():
args2 <- args
args$return_type <- "nmmin"
args2$return_type <- "vmmin"
system.time(fit <- .Call("aft_model_output", args, PACKAGE = "rstpm2"))
system.time(fit2 <- .Call("aft_model_output", args2, PACKAGE = "rstpm2"))
##
scale <- c(1,1,1,1,1)
as.vector(gradient(scale*init))
colSums(gradi(scale*init))
tmp <- sapply(1:length(init), function(i) {eps=1e-4; delta=rep(0,length(init)); delta[i]=eps; (neglli(scale*init+delta)-neglli(scale*init-delta))/(2*eps) })
apply(tmp - gradi(scale*init), 2, range)
##
## check designD and designDD
head(predict(design,logtstar+1e-5)-predict(design,logtstar-1e-5))/2e-5
head(predict(designD,logtstar))
head(predict(designD,logtstar+1e-5)-predict(designD,logtstar-1e-5))/2e-5
head(predict(designDD,logtstar))
##
aft1 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4,
init=coef(aft0))
init <- coef(aft0)
scale <- -1
negll(scale*init)
negll.slow(scale*init)
tmp <- sapply(1:length(init), function(i) {eps=1e-5; delta=rep(0,length(init)); delta[i]=eps; (neglli(scale*init+delta)-neglli(scale*init-delta))/(2*eps) })
head(tmp[!event,])
head(gradi(scale*init)[!event,])
head(tmp[event,])
head(gradi(scale*init)[event,])
range(tmp - gradi(scale*init))
}
parnames(negll) <- names(init)
## MLE
args$return_type <- if (use.gr) "vmmin" else "nmmin"
fit <- .Call("aft_model_output", args, PACKAGE="rstpm2")
args$init <- coef <- as.vector(fit$coef)
hessian <- fit$hessian
names(coef) <- rownames(hessian) <- colnames(hessian) <- names(init)
mle2 <- mle2(negll, coef, gr=gradient, vecpar=TRUE, control=control, ..., eval.only=TRUE)
mle2@vcov <- if (!inherits(vcov <- try(solve(hessian)), "try-error")) vcov else matrix(NA,length(coef), length(coef))
mle2@details$convergence <- fit$fail # fit$itrmcd
out <- as(mle2, "aft")
out@args <- args
return(out)
}
setMethod("predict", "aft",
function(object,newdata=NULL,
type=c("surv","cumhaz","hazard","density","hr","sdiff","hdiff","loghazard","link","meansurv","meansurvdiff","odds","or","meanhaz","af","fail","accfac"),
grid=FALSE,seqLength=300,
se.fit=FALSE,link=NULL,exposed=incrVar(var),var=NULL,keep.attributes=TRUE,...) {
type <- match.arg(type)
args <- object@args
if (type %in% c("fail")) {
out <- 1-predict(object,newdata=newdata,type="surv",grid,seqLength,se.fit,link,exposed,var,keep.attributes,...)
if (se.fit) {temp <- out$lower; out$lower <- out$upper; out$upper <- temp}
return(out)
}
if (is.null(exposed) && is.null(var) & type %in% c("hr","sdiff","hdiff","meansurvdiff","or","af","accfac"))
stop('Either exposed or var required for type in ("hr","sdiff","hdiff","meansurvdiff","or","af","accfac")')
## exposed is a function that takes newdata and returns the revised newdata
## var is a string for a variable that defines a unit change in exposure
if (is.null(newdata) && type %in% c("hr","sdiff","hdiff","meansurvdiff","or","af","accfac"))
stop("Prediction using type in ('hr','sdiff','hdiff','meansurvdiff','or','af','accfac') requires newdata to be specified.")
calcX <- !is.null(newdata)
time <- NULL
if (is.null(newdata)) {
##mm <- X <- model.matrix(object) # fails (missing timevar)
X <- args$X
XD <- args$XD
##y <- model.response(object@model.frame)
y <- args$y
time <- as.vector(y[,ncol(y)-1])
newdata <- as.data.frame(args$data)
}
lpfunc <- function(delta,fit,data,var) {
data[[var]] <- data[[var]]+delta
lpmatrix.lm(fit,data)
}
## resp <- attr(Terms, "variables")[attr(Terms, "response")]
## similarly for the derivatives
if (grid) {
Y <- args$y
event <- Y[,ncol(Y)]==1
time <- args$data[[args$timeVar]]
eventTimes <- time[event]
tt <- seq(min(eventTimes),max(eventTimes),length=seqLength)[-1]
data.x <- data.frame(tt)
names(data.x) <- args$timeVar
newdata[[args$timeVar]] <- NULL
newdata <- merge(newdata,data.x)
calcX <- TRUE
}
if (calcX) {
X <- lpmatrix.lm(args$lm.obj, newdata)
XD <- grad(lpfunc,0,args$lm.obj,newdata,args$timeVar)
XD <- matrix(XD,nrow=nrow(X))
time <- eval(args$timeExpr,newdata)
}
if (type %in% c("hr","sdiff","hdiff","meansurvdiff","or","af","accfac")) {
newdata2 <- exposed(newdata)
X2 <- lpmatrix.lm(args$lm.obj, newdata2)
XD2 <- grad(lpfunc,0,args$lm.obj,newdata2,args$timeVar)
XD2 <- matrix(XD2,nrow=nrow(X))
time2 <- eval(args$timeExpr,newdata2) # is this always equal to time?
}
## colMeans <- function(x) colSums(x)/apply(x,2,length)
local <- function (object, newdata=NULL, type="surv", exposed)
{
args <- object@args
betafull <- coef(object)
beta <- betafull[1:ncol(args$X)]
betas <- betafull[-(1:ncol(args$X))]
tt <- args$terms
eta <- as.vector(X %*% beta)
logtstar <- log(time) - eta
etas <- as.vector(predict(args$design, logtstar) %*% betas)
H <- exp(etas)
S <- exp(-H)
if (type=="cumhaz")
return(H)
if (type=="surv")
return(S)
if (type=="fail")
return(1-S)
if (type=="odds")
return((1-S)/S)
if (type=="meansurv")
return(tapply(S,newdata[[object@timeVar]],mean))
etaDs <- as.vector(predict(args$designD, logtstar) %*% betas)
etaD <- as.vector(XD %*% beta)
h <- H*etaDs*(1/time-etaD)
Sigma = vcov(object)
if (type=="link")
return(eta)
if (type=="density")
return (S*h)
if (type=="hazard")
return(h)
if (type=="loghazard")
return(log(h))
if (type=="meanhaz")
return(tapply(S*h,newdata[[object@timeVar]],sum)/tapply(S,newdata[[object@timeVar]],sum))
eta2 <- as.vector(X2 %*% beta)
logtstar2 <- log(time2) - eta2
etas2 <- as.vector(predict(args$design, logtstar2) %*% betas)
H2 <- exp(etas2)
S2 <- exp(-H2)
if (type=="sdiff")
return(S2-S)
if (type=="or")
return((1-S2)/S2/((1-S)/S))
if (type=="meansurvdiff")
return(tapply(S2,newdata[[object@timeVar]],mean) - tapply(S,newdata[[object@timeVar]],mean))
etaDs2 <- as.vector(predict(args$designD, logtstar2) %*% betas)
etaD2 <- as.vector(XD2 %*% beta)
h2 <- H2*etaDs2*(1/time2-etaD2)
if (type=="hdiff")
return(h2 - h)
if (type=="hr")
return(h2/h)
if (type=="af") {
meanS <- tapply(S,newdata[[object@timeVar]],mean)
meanS2 <- tapply(S2,newdata[[object@timeVar]],mean)
return((meanS2 - meanS)/(1-meanS))
}
if (type=="accfac") {
accfac <- eta - log(1-time*etaD)
accfac2 <- eta2 - log(1-time2*etaD2)
return(exp(accfac2-accfac))
}
}
pred <- if (!se.fit) {
local(object,newdata,type=type,exposed=exposed,
...)
}
else {
if (is.null(link))
link <- switch(type,surv="cloglog",cumhaz="log",hazard="log",hr="log",sdiff="I",
hdiff="I",loghazard="I",link="I",odds="log",or="log",meansurv="I",meanhaz="I",af="I",accfac="log")
predictnl(object,local,link=link,newdata=newdata,type=type,gd=NULL,
exposed=exposed,...)
}
if (keep.attributes)
attr(pred,"newdata") <- newdata
return(pred)
})
plot.aft.meansurv <- function(x, y=NULL, times=NULL, newdata=NULL, type="meansurv", exposed=NULL, add=FALSE, ci=!add, rug=!add, recent=FALSE,
xlab=NULL, ylab=NULL, lty=1, line.col=1, ci.col="grey", seqLength=301, ...) {
## if (is.null(times)) stop("plot.meansurv: times argument should be specified")
args <- x@args
if (is.null(newdata)) newdata <- as.data.frame(args$data)
if (is.null(times)) {
Y <- args$y
event <- Y[,ncol(Y)]==1
time <- args$data[[args$timeVar]]
eventTimes <- time[event]
times <- seq(min(eventTimes),max(eventTimes),length=seqLength)[-1]
}
times <- times[times !=0]
if (recent) {
newdata <- do.call("rbind",
lapply(times,
function(time) {
newd <- newdata
newd[[args$timeVar]] <- newdata[[args$timeVar]]*0+time
newd
}))
pred <- predict(x, newdata=newdata, type=type, se.fit=ci, exposed=exposed) # requires recent version
if (type=="meansurv")
pred <- if (ci) rbind(c(Estimate=1,lower=1,upper=1),pred) else c(1,pred)
} else {
pred <- lapply(times,
function(time) {
newdata[[args$timeVar]] <- newdata[[args$timeVar]]*0+time
predict(x, newdata=newdata, type=type, se.fit=ci, grid=FALSE, exposed=exposed)
})
pred <- do.call("rbind", pred)
if (type=="meansurv") {
pred <- if (ci) rbind(c(Estimate=1,lower=1,upper=1),pred) else c(1,unlist(pred))
times <- c(0,times)
}
}
if (is.null(xlab)) xlab <- deparse(args$timeExpr)
if (is.null(ylab))
ylab <- switch(type,
meansurv="Mean survival",
af="Attributable fraction",
meansurvdiff="Difference in mean survival")
if (!add) matplot(times, pred, type="n", xlab=xlab, ylab=ylab, ...)
if (ci) {
polygon(c(times,rev(times)),c(pred$lower,rev(pred$upper)),col=ci.col,border=ci.col)
lines(times,pred$Estimate,col=line.col,lty=lty,...)
} else {
lines(times,pred,col=line.col,lty=lty,...)
}
if (rug) {
Y <- args$y
eventTimes <- Y[Y[,ncol(Y)]==1,ncol(Y)-1]
rug(eventTimes,col=line.col)
}
return(invisible(y))
}
plot.aft.base <-
function(x,y,newdata=NULL,type="surv",
xlab=NULL,ylab=NULL,line.col=1,ci.col="grey",lty=par("lty"),
add=FALSE,ci=!add,rug=!add,
var=NULL,exposed=incrVar(var),times=NULL,...) {
if (type %in% c("meansurv","meansurvdiff","af")) {
return(plot.aft.meansurv(x,times=times,newdata=newdata,type=type,xlab=xlab,ylab=ylab,line.col=line.col,ci.col=ci.col,
lty=lty,add=add,ci=ci,rug=rug, exposed=exposed, ...))
}
args <- x@args
if (is.null(newdata)) stop("newdata argument needs to be specified")
y <- predict(x,newdata,type=switch(type,fail="surv",margfail="margsurv",type),var=var,exposed=exposed,
grid=!(args$timeVar %in% names(newdata)), se.fit=ci)
if (type %in% c("fail","margfail")) {
if (ci) {
y$Estimate <- 1-y$Estimate
lower <- y$lower
y$lower=1-y$upper
y$upper=1-lower
} else y <- structure(1-y,newdata=attr(y,"newdata"))
}
if (is.null(xlab)) xlab <- deparse(args$timeExpr)
if (is.null(ylab))
ylab <- switch(type,hr="Hazard ratio",hazard="Hazard",surv="Survival",density="Density",
sdiff="Survival difference",hdiff="Hazard difference",cumhaz="Cumulative hazard",
loghazard="log(hazard)",link="Linear predictor",meansurv="Mean survival",
meansurvdiff="Difference in mean survival",odds="Odds",or="Odds ratio",
margsurv="Marginal survival",marghaz="Marginal hazard",marghr="Marginal hazard ratio", haz="Hazard",fail="Failure",
meanhaz="Mean hazard",margfail="Marginal failure",af="Attributable fraction",meanmargsurv="Mean marginal survival",
uncured="Uncured distribution","Acceleration factor")
xx <- attr(y,"newdata")
xx <- eval(args$timeExpr,xx) # xx[,ncol(xx)]
if (!add) matplot(xx, y, type="n", xlab=xlab, ylab=ylab, ...)
if (ci) {
polygon(c(xx,rev(xx)), c(y[,2],rev(y[,3])), col=ci.col, border=ci.col)
lines(xx,y[,1],col=line.col,lty=lty,...)
} else lines(xx,y,col=line.col,lty=lty,...)
if (rug) {
Y <- args$y
eventTimes <- Y[Y[,ncol(Y)]==1,ncol(Y)-1]
rug(eventTimes,col=line.col)
}
return(invisible(y))
}
setMethod("plot", signature(x="aft", y="missing"),
function(x,y,newdata=NULL,type="surv",
xlab=NULL,ylab=NULL,line.col=1,ci.col="grey",lty=par("lty"),
add=FALSE,ci=!add,rug=!add,
var=NULL,exposed=incrVar(var),times=NULL,...)
plot.aft.base(x=x, y=y, newdata=newdata, type=type, xlab=xlab,
ylab=ylab, line.col=line.col, lty=lty, add=add,
ci=ci, rug=rug, var=var, exposed=exposed, times=times, ...)
)
predictSurvival.aft <- function(obj, time=obj@args$time, X=obj@args$X) {
localargs <- obj@args
localargs$return_type <- "survival"
localargs$X <- X
localargs$time <- time
as.vector(.Call("aft_model_output", localargs, PACKAGE="rstpm2"))
}
## simulate from Weibull with one binary covariate
if (FALSE) {
require(rstpm2)
summary(aft0 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4))
aft1 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4,init=coef(aft1))
require(rstpm2)
summary(aft0 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4))
plot(survfit(Surv(rectime,censrec==1)~hormon,data=brcancer),col=1:2)
plot(aft0,newdata=data.frame(hormon=0), add=TRUE, line.col="green", ci=FALSE)
plot(aft0,newdata=data.frame(hormon=1), add=TRUE, line.col="blue", ci=FALSE)
summary(aft1 <- aft(Surv(rectime,censrec==1)~hormon,data=brcancer,df=4,smooth.formula=~hormon:ns(log(rectime),df=3)))
plot(survfit(Surv(rectime,censrec==1)~hormon,data=brcancer),col=1:2)
plot(aft1,newdata=data.frame(hormon=0), add=TRUE, line.col="green", ci=FALSE)
plot(aft1,newdata=data.frame(hormon=1), add=TRUE, line.col="blue", ci=FALSE)
require(rstpm2)
require(survival)
require(splines)
set.seed(12345)
n <- 1e4
x <- rep(c(0,1),n/2)
af <- exp(0.3*x)
time <- rweibull(n,2,5)*af
censor <- rexp(n,rate=1/10)
obstime <- pmin(time,censor)
event <- ifelse(obstime==time,1,0)
X <- cbind(x)
XD <- X*0
dat1 <- data.frame(obstime,event,x)
aft1 <- aft(Surv(obstime,event)~x,data=dat1, df=2, reltol=1e-12, control=list(maxit=2000))
plot(survfit(Surv(obstime,event)~x,data=dat1),col=1:2)
plot(aft1,newdata=data.frame(x=0), add=TRUE, line.col="green", ci=FALSE)
plot(aft1,newdata=data.frame(x=1), add=TRUE, line.col="blue", ci=FALSE)
head(rstpm2:::predictSurvival.aft(aft1)) - head(predict(aft1))
plot(aft1,newdata=data.frame(x=0), type="hazard", line.col="green", rug=FALSE)
plot(aft1,newdata=data.frame(x=1), type="hazard", add=TRUE, line.col="blue", ci=TRUE)
aft2 <- aft(Surv(obstime,event)~x,data=dat1, df=4, reltol=1e-12, control=list(maxit=2000), smooth.formula=~x:ns(log(obstime),df=3))
plot(survfit(Surv(obstime,event)~x,data=dat1),col=1:2)
plot(aft2,newdata=data.frame(x=0),line.col="green",add=TRUE,ci=FALSE)
plot(aft2,newdata=data.frame(x=1),line.col="blue",add=TRUE,ci=FALSE)
plot(aft2,newdata=data.frame(x=0),type="accfac",exposed=function(data) transform(data,x=1),se.fit=TRUE)
aft3 <- aft(Surv(obstime,event)~x,data=dat1, df=4, reltol=1e-12, control=list(maxit=2000), smooth.formula=~x:ns(obstime,df=3))
plot(aft3,newdata=data.frame(x=0),type="accfac",exposed=function(data) transform(data,x=1))
plot(aft2,newdata=data.frame(x=0),type="accfac",exposed=function(data) transform(data,x=1),ci=FALSE,add=TRUE,line.col="blue")
## f$fn is not the same (?!)
aft1$negll(aft1$par)
-sum(aft1$logh*event-aft1$H) # ok
-sum(aft1$f$report(aft1$par)$logh*event-aft1$f$report(aft1$par)$H) # ok
-sum(aft2$f$report(aft1$par)$logh*event-aft2$f$report(aft1$par)$H) # ok
aft1$f$fn(aft1$par) # ???
## f$fn is not the same (?!)
aft2$negll(aft2$par)
-sum(aft2$logh*event-aft2$H) # ok
-sum(aft2$f$report(aft2$par)$logh*dat1$event-aft2$f$report(aft2$par)$H) # ok
aft2$f$fn(aft2$par) # ???
## the events are the same
all(event == aft1$f$report(aft1$par)$event) # ok
all(event == aft2$f$report(aft2$par)$event) # ok
## The H and logh vectors are very close
max(abs(aft1$f$report(aft1$par)$H - aft1$H)) # ok
max(abs(aft2$f$report(aft2$par)$H - aft2$H)) # ok
max(abs(aft1$f$report(aft1$par)$logh - aft1$logh)) # ok
max(abs(aft2$f$report(aft2$par)$logh - aft2$logh)) # ok
##
## the Xs and XDs matrices are very close
max(abs(aft1$f$report(aft1$par)$Xs - aft1$Xs)) # ok
max(abs(aft1$f$report(aft1$par)$XDs - aft1$XDs)) # ok
max(abs(aft2$f$report(aft2$par)$Xs - aft2$Xs)) # ok
max(abs(aft2$f$report(aft2$par)$XDs - aft2$XDs)) # ok
head(aft1$Xs)
head(aft2$Xs)
head(aft1$f$report(aft1$par)$Xs)
head(aft1$f$report(aft2$par)$Xs)
head(aft2$f$report(aft2$par)$Xs)
aft1$f$gr(aft1$par) # ok
delta=function(i,eps=1e-5) {new=rep(0,5); new[i]=eps; new}
for (i in 1:length(aft1$par))
print((aft1$f$fn(aft1$par+delta(i))-aft1$f$fn(aft1$par-delta(i)))/(2e-5))
## Gradient at the 'final' value are not the same
for (i in 1:length(aft2$par))
print((aft2$negll(aft1$par+delta(i))-aft2$negll(aft1$par-delta(i)))/(2e-5))
## gradient at the initial value are the same
aft1$f$gr(aft1$init) # ok
delta=function(i,eps=1e-5) {new=rep(0,5); new[i]=eps; new}
for (i in 1:length(aft1$par))
print((aft1$f$fn(aft1$init+delta(i))-aft1$f$fn(aft1$init-delta(i)))/(2e-5))
## Objective at the initial values are the same
as.numeric(aft1$negll(aft1$init)) - aft1$f$fn(aft1$init) # ok
as.numeric(aft2$negll(aft2$init)) - aft2$f$fn(aft2$init) # ok
## objectives at the 'final' values are NOT the same
as.numeric(aft1$negll(aft1$init+0.1)) - aft1$f$fn(aft1$init+0.1) # ??
as.numeric(aft1$negll(aft1$par)) - aft1$f$fn(aft1$par) # ???
undebug(aft1$negll)
aft1$negll(aft1$par)
aft1$init
aft1$f$par
aft1$f$fn(aft1$init)
aft1$f$fn(aft1$f$par)
aft1$f$fn(aft1$par)
aft1$f$fn(aft2$par)
}
