2
0
Fork 0

add: multivariate response to tensorflow wip.

This commit is contained in:
Daniel Kapla 2020-09-11 19:30:35 +02:00
parent 4a950d6df2
commit 025b9eb2af
1 changed files with 50 additions and 16 deletions

View File

@ -43,6 +43,7 @@ tf_constant <- function(obj, dtype = "float32", ...) {
cve.tf <- function(X, Y, k, h = estimate.bandwidth(X, k, sqrt(nrow(X))), cve.tf <- function(X, Y, k, h = estimate.bandwidth(X, k, sqrt(nrow(X))),
V.init = NULL, optimizer_initialier = tf$optimizers$RMSprop, attempts = 10L, V.init = NULL, optimizer_initialier = tf$optimizers$RMSprop, attempts = 10L,
nr.projections = nrow(X)^(3 / 2),
sd_noise = 0, method = c("simple", "weighted") sd_noise = 0, method = c("simple", "weighted")
) { ) {
method <- match.arg(method) method <- match.arg(method)
@ -55,15 +56,25 @@ cve.tf <- function(X, Y, k, h = estimate.bandwidth(X, k, sqrt(nrow(X))),
k <- as.integer(k) k <- as.integer(k)
q <- p - k q <- p - k
if (!is.matrix(Y))
Y <- as.matrix(Y)
# Projective resampling.
if (ncol(Y) > 1L) {
R <- matrix(rnorm(ncol(Y) * nr.projections), ncol(Y))
R <- t(t(R) / sqrt(colSums(R^2)))
Y <- Y %*% R
}
X <- tf_constant(scale(X)) X <- tf_constant(scale(X))
Y <- tf_constant(scale(as.matrix(Y))) Y <- tf_constant(scale(Y))
I <- tf_constant(diag(1, p)) I <- tf_constant(diag(1, p))
h <- tf_Variable(h) h <- tf_Variable(h)
loss <- tf_function(function(V) { loss <- tf_function(function(V) {
Q <- I - tf$matmul(V, V, transpose_b = TRUE) Q <- I - tf$matmul(V, V, transpose_b = TRUE)
if (sd_noise > 0) if (sd_noise > 0)
XQ <- tf$matmul(X + tf$random$normal(list(n, p), stddev = 0.05), Q) XQ <- tf$matmul(X + tf$random$normal(list(n, p), stddev = sd_noise), Q)
else else
XQ <- tf$matmul(X, Q) XQ <- tf$matmul(X, Q)
S <- tf$matmul(XQ, XQ, transpose_b = TRUE) S <- tf$matmul(XQ, XQ, transpose_b = TRUE)
@ -76,9 +87,10 @@ cve.tf <- function(X, Y, k, h = estimate.bandwidth(X, k, sqrt(nrow(X))),
if (method == "simple") { if (method == "simple") {
l <- tf$reduce_mean(y2 - tf$pow(y1, 2L)) l <- tf$reduce_mean(y2 - tf$pow(y1, 2L))
} else {# weighted } else {# weighted
w <- tf$reduce_sum(K, 1L, keepdims = TRUE) - `1` # TODO: check/fix w <- w - `1`
w <- w / tf$reduce_sum(w) w <- w / tf$reduce_sum(w)
l <- tf$reduce_sum(w * (y2 - tf$pow(y1, 2L))) l <- tf$reduce_sum(w * (y2 - tf$pow(y1, 2L)))
l <- l / tf$cast(tf$shape(Y)[2], "float32")
} }
l l
}) })
@ -129,36 +141,58 @@ plot.sim <- function(sim) {
lines(density(ssd, from = 0, to = 1)) lines(density(ssd, from = 0, to = 1))
stat <- c(Median = median(ssd), Mean = mean(ssd)) stat <- c(Median = median(ssd), Mean = mean(ssd))
abline(v = stat, lty = 2) abline(v = stat, lty = 2)
text(stat, 1.02 * max(h$density), names(stat), text(stat, max(h$density), names(stat),
pos = if(diff(stat) > 0) c("2", "4") else c("4", "2")) pos = if(diff(stat) > 0) c("2", "4") else c("4", "2"))
} }
multivariate.dataset <- function(n = 100, p = 6, q = 4) {
CVE <- getNamespace('CVE')
X <- matrix(rnorm(n * p), n, p)
Delta <- diag(1, q, q)
Delta[1, 2] <- Delta[2, 1] <- -0.5
epsilon <- CVE$rmvnorm(n, sigma = Delta)
B <- matrix(0, p, q)
B[1, 1] <- 1
B[2, 2] <- 2 / sqrt(5)
B[3, 2] <- 1 / sqrt(5)
Y <- X %*% B + epsilon
list(X = X, Y = Y, B = B[, 1:2])
}
set.seed(42) set.seed(42)
sim.cve <- vector("list", 100) reps <- 10L
sim.tf1 <- vector("list", 100) sim.cve <- vector("list", reps)
sim.tf2 <- vector("list", 100) sim.tf1 <- vector("list", reps)
sim.tf2 <- vector("list", reps)
start <- Sys.time() start <- Sys.time()
for (i in 1:100) { for (i in 1:reps) {
ds <- dataset(1) # ds <- dataset(1)
ds <- multivariate.dataset()
sim.cve[[i]] <- list( # sim.cve[[i]] <- list(
B.est = coef(CVE::cve.call(ds$X, ds$Y, k = ncol(ds$B)), ncol(ds$B)), # B.est = coef(CVE::cve.call(ds$X, ds$Y, k = ncol(ds$B)), ncol(ds$B)),
B.true = ds$B # B.true = ds$B
) # )
sim.tf1[[i]] <- list( sim.tf1[[i]] <- list(
B.est = cve.tf(ds$X, ds$Y, ncol(ds$B))$B, B.est = cve.tf(ds$X, ds$Y, ncol(ds$B),
optimizer_initialier = tf$optimizers$Adam)$B,
B.true = ds$B B.true = ds$B
) )
sim.tf2[[i]] <- list( sim.tf2[[i]] <- list(
B.est = cve.tf(ds$X, ds$Y, ncol(ds$B), sd_noise = 0.05)$B, B.est = cve.tf(ds$X, ds$Y, ncol(ds$B),
optimizer_initialier = tf$optimizers$Adam,
method = "weighted")$B,
B.true = ds$B B.true = ds$B
) )
cat(sprintf("\r%4d/100 -", i), format(Sys.time() - start), '\n') cat(sprintf("\r%4d/%d -", i, reps), format(Sys.time() - start), '\n')
} }
# pdf('subspace_comp.pdf') # pdf('subspace_comp.pdf')