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# Copyright 2005-2012 by Roger Bivand
spautolm <- function(formula, data = list(), listw, weights,
na.action, family="SAR", method="eigen", verbose=NULL, trs=NULL,
interval=NULL, zero.policy=NULL, tol.solve=.Machine$double.eps, llprof=NULL,
control=list()) {
timings <- list()
.ptime_start <- proc.time()
con <- list(tol.opt=.Machine$double.eps^(2/3),
fdHess=NULL, optimHess=FALSE, optimHessMethod="optimHess",
Imult=2, cheb_q=5, MC_p=16, MC_m=30, super=NULL, spamPivot="MMD",
in_coef=0.1, type="MC",
correct=TRUE, trunc=TRUE, SE_method="LU", nrho=200,
interpn=2000, small_asy=TRUE, small=1500, SElndet=NULL,
LU_order=FALSE, pre_eig=NULL)
nmsC <- names(con)
con[(namc <- names(control))] <- control
if (length(noNms <- namc[!namc %in% nmsC]))
warning("unknown names in control: ", paste(noNms, collapse = ", "))
if (!inherits(listw, "listw"))
stop("No neighbourhood list")
if (is.null(verbose)) verbose <- get("verbose", envir = .spdepOptions)
stopifnot(is.logical(verbose))
if (is.null(zero.policy))
zero.policy <- get("zeroPolicy", envir = .spdepOptions)
stopifnot(is.logical(zero.policy))
if (family == "SMA" && method != "eigen") stop("SMA only for eigen method")
if (method == "spam" || method == "spam_update") stop("spam not supported as method")
mf <- match.call(expand.dots = FALSE)
m <- match(c("formula", "data", "weights", "na.action"), names(mf), 0)
mf <- mf[c(1, m)]
mf$drop.unused.levels <- TRUE
mf[[1]] <- as.name("model.frame")
mf <- eval(mf, parent.frame())
mt <- attr(mf, "terms")
# mt <- terms(formula, data = data)
# mf <- lm(formula, data, , weights, na.action=na.action,
# method="model.frame")
na.act <- attr(mf, "na.action")
if (!is.null(na.act)) {
subset <- !(1:length(listw$neighbours) %in% na.act)
listw <- subset(listw, subset, zero.policy=zero.policy)
}
Y <- model.extract(mf, "response")
if (any(is.na(Y))) stop("NAs in dependent variable")
X <- model.matrix(mt, mf)
if (any(is.na(X))) stop("NAs in independent variable")
n <- nrow(X)
if (n != length(listw$neighbours))
stop("Input data and neighbourhood list have different dimensions")
weights <- as.vector(model.extract(mf, "weights"))
# set up default weights
if (!is.null(weights) && !is.numeric(weights))
stop("'weights' must be a numeric vector")
if (is.null(weights)) weights <- rep(as.numeric(1), n)
if (any(is.na(weights))) stop("NAs in weights")
if (any(weights < 0)) stop("negative weights")
lm.base <- lm(Y ~ X - 1, weights=weights)
aliased <- is.na(coefficients(lm.base))
cn <- names(aliased)
names(aliased) <- substr(cn, 2, nchar(cn))
if (any(aliased)) {
nacoef <- which(aliased)
# bug x for X Bjarke Christensen 090924
X <- X[,-nacoef]
}
can.sim <- FALSE
if (listw$style %in% c("W", "S"))
can.sim <- can.be.simmed(listw)
sum_lw <- sum(log(weights))
# env <- new.env(parent=globalenv())
env <- new.env()
assign("Y", Y, envir=env)
assign("X", X, envir=env)
assign("n", n, envir=env)
assign("weights", weights, envir=env)
assign("can.sim", can.sim, envir=env)
assign("family", family, envir=env)
assign("method", method, envir=env)
assign("verbose", verbose, envir=env)
assign("listw", listw, envir=env)
assign("sum_lw", sum_lw, envir=env)
W <- as(listw, "CsparseMatrix")
if (family == "CAR") if (!isTRUE(all.equal(W, t(W))))
warning("Non-symmetric spatial weights in CAR model")
assign("W", W, envir=env)
I <- as_dsCMatrix_I(n)
assign("I", I, envir=env)
Sweights <- as(as(Diagonal(x=weights), "symmetricMatrix"),
"CsparseMatrix")
assign("Sweights", Sweights, envir=env)
timings[["set_up"]] <- proc.time() - .ptime_start
.ptime_start <- proc.time()
if (verbose) cat(paste("\nJacobian calculated using "))
interval <- jacobianSetup(method, env, con, pre_eig=con$pre_eig, trs=trs,
interval=interval)
assign("interval", interval, envir=env)
# fix SMA bounds
if (family == "SMA") interval <- -rev(interval)
nm <- paste(method, "set_up", sep="_")
timings[[nm]] <- proc.time() - .ptime_start
.ptime_start <- proc.time()
if (!is.null(llprof)) {
if (length(llprof) == 1L)
llprof <- seq(interval[1], interval[2], length.out=llprof)
ll_prof <- numeric(length(llprof))
for (i in seq(along=llprof))
ll_prof[i] <- .opt.fit(llprof[i], env=env, tol.solve=tol.solve)
nm <- paste(method, "profile", sep="_")
timings[[nm]] <- proc.time() - .ptime_start
.ptime_start <- proc.time()
}
opt <- optimize(.opt.fit, interval=interval, maximum=TRUE,
tol = con$tol.opt, env=env, tol.solve=tol.solve)
lambda <- opt$maximum
if (isTRUE(all.equal(lambda, interval[1])) ||
isTRUE(all.equal(lambda, interval[2])))
warning("lambda on interval bound - results should not be used")
names(lambda) <- "lambda"
LL <- opt$objective
nm <- paste(method, "opt", sep="_")
timings[[nm]] <- proc.time() - .ptime_start
.ptime_start <- proc.time()
# get GLS coefficients
fit <- .SPAR.fit(lambda=lambda, env, out=TRUE, tol.solve=tol.solve)
# create residuals and fitted values (Cressie 1993, p. 564)
fit$signal_trend <- drop(X %*% fit$coefficients)
fit$signal_stochastic <- drop(lambda * W %*% (Y - fit$signal_trend))
fit$fitted.values <- fit$signal_trend + fit$signal_stochastic
fit$residuals <- drop(Y - fit$fitted.values)
# get null LL
LL0 <- .opt.fit(lambda=0, env, tol.solve=tol.solve)
# NK null
LLNullLlm <- logLik(lm(Y ~ 1, weights=weights))
nm <- paste(method, "output", sep="_")
timings[[nm]] <- proc.time() - .ptime_start
.ptime_start <- proc.time()
# if (method != "eigen") {
# if (con$small >= n && con$small_asy) do_asy <- TRUE
# else do_asy <- FALSE
# } else do_asy <- TRUE
do_asy <- FALSE
if (is.null(con$fdHess)) {
con$fdHess <- !do_asy #&& method != "eigen"
fdHess <- NULL
}
stopifnot(is.logical(con$fdHess))
lambda.se <- NULL
if (con$fdHess) {
coefs <- c(lambda, fit$coefficients)
fdHess <- getVcovmat(coefs, env, tol.solve=tol.solve,
optim=con$optimHess, optimM=con$optimHessMethod)
lambda.se <- sqrt(fdHess[1, 1])
}
timings[["fdHess"]] <- proc.time() - .ptime_start
rm(env)
GC <- gc()
res <- list(fit=fit, lambda=lambda, LL=LL, LL0=LL0, call=match.call(),
parameters=(ncol(X)+2), aliased=aliased, method=method, family=family,
zero.policy=zero.policy, weights=weights, interval=interval, trs=trs,
timings=do.call("rbind", timings)[, c(1, 3)], LLNullLlm=LLNullLlm,
fdHess=fdHess, lambda.se=lambda.se, X=X, Y=Y)
if (!is.null(na.act))
res$na.action <- na.act
if (is.null(llprof)) res$llprof <- llprof
else {
res$llprof <- list(lambda=llprof, ll=ll_prof)
}
if (zero.policy) {
zero.regs <- attr(listw$neighbours,
"region.id")[which(card(listw$neighbours) == 0)]
if (length(zero.regs) > 0L)
attr(res, "zero.regs") <- zero.regs
}
class(res) <- "spautolm"
res
}
.opt.fit <- function(lambda, env, tol.solve=.Machine$double.eps) {
# fitting function called from optimize()
SSE <- .SPAR.fit(lambda=lambda, env=env, out=FALSE, tol.solve=tol.solve)
n <- get("n", envir=env)
s2 <- SSE/n
ldet <- do_ldet(lambda, env)
det <- ifelse(get("family", envir=env) == "CAR", 0.5*ldet, ldet)
ret <- (det + (1/2)*get("sum_lw", envir=env) - ((n/2)*log(2*pi)) -
(n/2)*log(s2) - (1/(2*(s2)))*SSE)
if (get("verbose", envir=env)) cat("lambda:", lambda, "function:", ret, "Jacobian", ldet, "SSE", SSE, "\n")
ret
}
.SPAR.fit <- function(lambda, env, out=FALSE, tol.solve=.Machine$double.eps) {
dmmf <- eval(parse(text=get("family", envir=env)))
if (get("family", envir=env) == "SMA") IlW <- dmmf((get("I", envir=env) +
lambda * get("W", envir=env)), get("Sweights", envir=env))
else IlW <- dmmf((get("I", envir=env) - lambda * get("W", envir=env)),
get("Sweights", envir=env))
X <- get("X", envir=env)
Y <- get("Y", envir=env)
imat <- base::solve(crossprod(X, as.matrix(IlW %*% X)), tol=tol.solve)
coef <- crossprod(imat, crossprod(X, as.matrix(IlW %*% Y)))
fitted <- X %*% coef
residuals <- Y - fitted
SSE <- c(crossprod(residuals, as.matrix(IlW %*% residuals)))
if (!out) return(SSE)
n <- get("n", envir=env)
s2 <- SSE/n
# var <- s2 * diag(imat)
coef <- c(coef)
names(coef) <- colnames(X)
res <- list(coefficients=coef, SSE=c(SSE), s2=c(s2), imat=imat,
N=length(residuals))
res
}
# Simultaneous autoregressive
SAR <- function(IlW, weights) {
t(IlW) %*% weights %*% IlW
}
# Conditional autoregressive
CAR <- function(IlW, weights) {
IlW %*% weights
}
# Spatial moving average
SMA <- function(IlW, weights) {
IlW <- solve(IlW)
t(IlW) %*% weights %*% IlW
}
print.spautolm <- function(x, ...) {
if (isTRUE(all.equal(x$lambda, x$interval[1])) ||
isTRUE(all.equal(x$lambda, x$interval[2])))
warning("lambda on interval bound - results should not be used")
cat("\nCall:\n")
print(x$call)
cat("\nCoefficients:\n")
print(coef(x))
cat("\nLog likelihood:", logLik(x), "\n")
invisible(x)
}
residuals.spautolm <- function(object, ...) {
if (is.null(object$na.action))
object$fit$residuals
else napredict(object$na.action, object$fit$residuals)
}
fitted.spautolm <- function(object, ...) {
if (is.null(object$na.action))
object$fit$fitted.values
else napredict(object$na.action, object$fit$fitted.values)
}
deviance.spautolm <- function(object, ...) {
object$SSE
}
coef.spautolm <- function(object, ...) {
c(object$fit$coefficients, object$lambda)
}
logLik.spautolm <- function(object, ...) {
LL <- c(object$LL)
class(LL) <- "logLik"
N <- object$fit$N
attr(LL, "nall") <- N
attr(LL, "nobs") <- N
attr(LL, "df") <- object$parameters
LL
}
LR1.spautolm <- function(object)
{
if (!inherits(object, "spautolm")) stop("Not a spautolm object")
LLx <- logLik(object)
LLy <- object$LL0
statistic <- 2*(LLx - LLy)
attr(statistic, "names") <- "Likelihood ratio"
parameter <- 1
attr(parameter, "names") <- "df"
p.value <- 1 - pchisq(abs(statistic), parameter)
estimate <- c(LLx, LLy)
attr(estimate, "names") <- c(paste("Log likelihood of spatial regression fit"), paste("Log likelihood of OLS fit",
deparse(substitute(y))))
method <- "Likelihood Ratio diagnostics for spatial dependence"
res <- list(statistic=statistic, parameter=parameter,
p.value=p.value, estimate=estimate, method=method)
class(res) <- "htest"
res
}
summary.spautolm <- function(object, correlation = FALSE, adj.se=FALSE,
Nagelkerke=FALSE, ...) {
N <- object$fit$N
adj <- ifelse (adj.se, N/(N-length(object$fit$coefficients)), 1)
object$fit$s2 <- object$fit$s2*adj
object$resvar <- object$fit$s2*object$fit$imat
rownames(object$resvar) <- colnames(object$resvar) <-
names(object$fit$coefficients)
object$adj.se <- adj.se
object$rest.se <- sqrt(diag(object$resvar))
object$Coef <- cbind(object$fit$coefficients, object$rest.se,
object$fit$coefficients/object$rest.se,
2*(1-pnorm(abs(object$fit$coefficients/object$rest.se))))
colnames(object$Coef) <- c("Estimate", "Std. Error",
ifelse(adj.se, "t value", "z value"), "Pr(>|z|)")
if (Nagelkerke) {
nk <- NK.sarlm(object)
if (!is.null(nk)) object$NK <- nk
}
if (correlation) {
object$correlation <- diag((diag(object$resvar))
^(-1/2)) %*% object$resvar %*%
diag((diag(object$resvar))^(-1/2))
dimnames(object$correlation) <- dimnames(object$resvar)
}
object$LR1 <- LR1.spautolm(object)
rownames(object$Coef) <- names(object$fit$coefficients)
structure(object, class=c("summary.spautolm", class(object)))
}
print.summary.spautolm <- function(x, digits = max(5, .Options$digits - 3),
signif.stars = FALSE, ...)
{
cat("\nCall: ", deparse(x$call), sep = "", fill=TRUE)
if (isTRUE(all.equal(x$lambda, x$interval[1])) ||
isTRUE(all.equal(x$lambda, x$interval[2])))
warning("lambda on interval bound - results should not be used")
cat("\nResiduals:\n")
resid <- residuals(x)
nam <- c("Min", "1Q", "Median", "3Q", "Max")
rq <- if (length(dim(resid)) == 2L)
structure(apply(t(resid), 1, quantile), dimnames = list(nam,
dimnames(resid)[[2]]))
else structure(quantile(resid), names = nam)
print(rq, digits = digits, ...)
if (x$zero.policy) {
zero.regs <- attr(x, "zero.regs")
if (!is.null(zero.regs))
cat("\nRegions with no neighbours included:\n",
zero.regs, "\n")
}
cat("\nCoefficients:", x$coeftitle, "\n")
coefs <- x$Coef
if (!is.null(aliased <- x$aliased) && any(x$aliased)){
cat(" (", table(aliased)["TRUE"],
" not defined because of singularities)\n", sep = "")
cn <- names(aliased)
coefs <- matrix(NA, length(aliased), 4, dimnames = list(cn,
colnames(x$Coef)))
coefs[!aliased, ] <- x$Coef
}
printCoefmat(coefs, signif.stars=signif.stars, digits=digits,
na.print="NA")
res <- x$LR1
cat("\nLambda:", format(signif(x$lambda, digits)),
"LR test value:", format(signif(res$statistic, digits)),
"p-value:", format.pval(res$p.value, digits),
"\n")
if (!is.null(x$lambda.se))
cat("Numerical Hessian standard error of lambda:",
format(signif(x$lambda.se, digits)), "\n")
cat("\nLog likelihood:", logLik(x), "\n")
if (x$adj.se) cat("Residual variance (sigma squared): ")
else cat("ML residual variance (sigma squared): ")
cat(format(signif(x$fit$s2, digits)), ", (sigma: ",
format(signif(sqrt(x$fit$s2), digits)), ")\n", sep="")
cat("Number of observations:", x$fit$N, "\n")
cat("Number of parameters estimated:", x$parameters, "\n")
cat("AIC: ", format(signif(AIC(x), digits)), "\n", sep="")
if (!is.null(x$NK)) cat("Nagelkerke pseudo-R-squared:",
format(signif(x$NK, digits)), "\n")
correl <- x$correlation
if (!is.null(correl)) {
p <- NCOL(correl)
if (p > 1) {
cat("\nCorrelation of Coefficients:\n")
correl <- format(round(correl, 2), nsmall = 2,
digits = digits)
correl[!lower.tri(correl)] <- ""
print(correl[-1, -p, drop = FALSE], quote = FALSE)
}
}
cat("\n")
invisible(x)
}
getVcovmat <- function(coefs, env, tol.solve=.Machine$double.eps, optim=FALSE,
optimM="optimHess") {
if (optim) {
if (optimM == "nlm") {
options(warn=-1)
opt <- nlm(f=f_spautolm_hess_nlm, p=coefs, env=env, hessian=TRUE)
options(warn=0)
mat <- opt$hessian
# opt <- optimHess(par=coefs, fn=f_laglm_hess, env=env)
# mat <- opt
} else if (optimM == "optimHess") {
mat <- optimHess(par=coefs, fn=f_spautolm_hess, env=env)
} else {
opt <- optim(par=coefs, fn=f_spautolm_hess, env=env, method=optimM,
hessian=TRUE)
mat <- opt$hessian
}
# opt <- optimHess(par=coefs, fn=f_spautolm_hess, env=env)
# mat <- opt
} else {
fd <- fdHess(coefs, f_spautolm_hess, env)
mat <- fd$Hessian
}
res <- solve(-(mat), tol.solve=tol.solve)
res
}
f_spautolm_hess_nlm <- function(coefs, env) {
ret <- f_spautolm_hess(coefs, env)
-ret
}
f_spautolm_hess <- function(coefs, env) {
lambda <- coefs[1]
int <- get("interval", envir=env)
if (lambda <= int[1] || lambda >= int[2]) return(-Inf)
beta <- coefs[-1]
X <- get("X", envir=env)
Y <- get("Y", envir=env)
fitted <- X %*% beta
residuals <- Y - fitted
dmmf <- eval(parse(text=get("family", envir=env)))
if (get("family", envir=env) == "SMA") IlW <- dmmf((get("I", envir=env) +
lambda * get("W", envir=env)), get("Sweights", envir=env))
else IlW <- dmmf((get("I", envir=env) - lambda * get("W", envir=env)),
get("Sweights", envir=env))
SSE <- c(crossprod(residuals, as.matrix(IlW %*% residuals)))
n <- get("n", envir=env)
s2 <- SSE/n
ldet <- do_ldet(lambda, env)
det <- ifelse(get("family", envir=env) == "CAR", 0.5*ldet, ldet)
ret <- (det + (1/2)*get("sum_lw", envir=env) - ((n/2)*log(2*pi)) -
(n/2)*log(s2) - (1/(2*(s2)))*SSE)
if (get("verbose", envir=env))
cat("lambda:", lambda, "function:", ret, "Jacobian", ldet, "SSE",
SSE, "\n")
if (!is.finite(ret)) return(-Inf)
ret
}
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