####################
# Author: James Hickey
#
# Series of tests to check that the basic gbm behaviour
#
####################
context("some basic checks")
test_that("gaussian works", {
skip_on_cran()
## Based on example in R package
## test Gaussian distribution gbm model
set.seed(1)
# create some data
N <- 1000
X1 <- runif(N)
X2 <- 2*runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
X4 <- ordered(sample(letters[1:6],N,replace=T))
X5 <- factor(sample(letters[1:3],N,replace=T))
X6 <- 3*runif(N)
mu <- c(-1,0,1,2)[as.numeric(X3)]
SNR <- 10 # signal-to-noise ratio
Y <- X1**1.5 + 2 * (X2**.5) + mu
sigma <- sqrt(var(Y)/SNR)
Y <- Y + rnorm(N,0,sigma)
# create a bunch of missing values
X1[sample(1:N,size=100)] <- NA
X3[sample(1:N,size=300)] <- NA
w <- rep(1,N)
offset <- rep(0, N)
data <- data.frame(Y=Y,X1=X1,X2=X2,X3=X3,X4=X4,X5=X5,X6=X6)
# Set up for new API
params <- training_params(num_trees=2000, interaction_depth=3, min_num_obs_in_node=10,
shrinkage=0.005, bag_fraction=0.5, id=seq(nrow(data)), num_train=N/2, num_features=6)
dist <- gbm_dist("Gaussian")
fit <- gbmt(Y~X1+X2+X3+X4+X5+X6, data=data, distribution=dist, weights=w, offset=offset,
train_params=params, var_monotone=c(0, 0, 0, 0, 0, 0), keep_gbm_data=TRUE, cv_folds=10, is_verbose=FALSE)
best_iter <- gbmt_performance(fit, method="cv") # returns test set estimate of best number of trees
# Make prediction
set.seed(2)
# make some new data
N <- 1000
X1 <- runif(N)
X2 <- 2*runif(N)
X3 <- factor(sample(letters[1:4],N,replace=TRUE))
X4 <- ordered(sample(letters[1:6],N,replace=TRUE))
X5 <- factor(sample(letters[1:3],N,replace=TRUE))
X6 <- 3*runif(N)
mu <- c(-1,0,1,2)[as.numeric(X3)]
# Actual underlying signal - Check how close to this we are
Y <- X1**1.5 + 2 * (X2**.5) + mu
data2 <- data.frame(Y=Y,X1=X1,X2=X2,X3=X3,X4=X4,X5=X5,X6=X6)
# predict on the new data using "best" number of trees
f.predict <- predict(fit, data2, best_iter) # f.predict will be on the canonical scale (logit,log,etc.)
# Base the validation tests on observed discrepancies
expect_true(cor(data2$Y, f.predict) > 0.990)
expect_true(sd(data2$Y-f.predict) < sigma)
})
test_that("coxph works - efron", {
skip_on_cran()
# Require Surv to be available
require(survival)
# create some data
set.seed(1)
N <- 3000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
f <- 0.5*sin(3*X1 + 5*X2^2 + mu/10)
tt.surv <- rexp(N,exp(f))
tt.cens <- rexp(N,0.5)
delta <- as.numeric(tt.surv <= tt.cens)
tt <- apply(cbind(tt.surv,tt.cens),1,min)
# throw in some missing values
X1[sample(1:N,size=100)] <- NA
X3[sample(1:N,size=300)] <- NA
# random weights if you want to experiment with them
w <- rep(1,N)
data <- data.frame(tt=tt,delta=delta,X1=X1,X2=X2,X3=X3)
# Put into new API
dist <- gbm_dist("CoxPH", prior_node_coeff_var=10)
params <- training_params(num_trees=3000, interaction_depth=3, min_num_obs_in_node=10,
shrinkage=0.001, bag_fraction=0.5, id=seq(nrow(data)), num_train=N/2, num_features=3)
# fit initial model
gbm1 <- gbmt(Surv(tt,delta)~X1+X2+X3, data=data, distribution=dist, weights=w, offset=rep(0, N),
train_params=params, var_monotone=c(0, 0, 0), keep_gbm_data=TRUE, cv_folds=5, is_verbose=FALSE)
best_iter <- gbmt_performance(gbm1, method="test") # returns test set estimate of best number of trees
# make some new data
set.seed(2)
N <- 1000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
f <- 0.5*sin(3*X1 + 5*X2^2 + mu/10) # -0.5 <= f <= 0.5 via sin fn.
tt.surv <- rexp(N,exp(f))
tt.cens <- rexp(N,0.5)
data2 <- data.frame(tt=apply(cbind(tt.surv,tt.cens),1,min),
delta=as.numeric(tt.surv <= tt.cens),
f=f,
X1=X1,X2=X2,X3=X3)
# predict on the new data using "best" number of trees
# f.predict will be on the canonical scale (logit,log,etc.)
f.predict <- predict(gbm1, data2, best_iter)
#plot(data2$f,f.predict)
# Use observed sd
expect_true(sd(data2$f - f.predict) < 0.4)
})
test_that("coxph works - breslow", {
skip_on_cran()
# Require Surv to be available
require(survival)
# create some data
set.seed(1)
N <- 3000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
f <- 0.5*sin(3*X1 + 5*X2^2 + mu/10)
tt.surv <- rexp(N,exp(f))
tt.cens <- rexp(N,0.5)
delta <- as.numeric(tt.surv <= tt.cens)
tt <- apply(cbind(tt.surv,tt.cens),1,min)
# throw in some missing values
X1[sample(1:N,size=100)] <- NA
X3[sample(1:N,size=300)] <- NA
# random weights if you want to experiment with them
w <- rep(1,N)
data <- data.frame(tt=tt,delta=delta,X1=X1,X2=X2,X3=X3)
# Put into new API
dist <- gbm_dist("CoxPH", prior_node_coeff_var=10, ties="breslow")
params <- training_params(num_trees=3000, interaction_depth=3, min_num_obs_in_node=10,
shrinkage=0.001, bag_fraction=0.5, id=seq(nrow(data)), num_train=N/2, num_features=3)
# fit initial model
gbm1 <- gbmt(Surv(tt,delta)~X1+X2+X3, data=data, distribution=dist, weights=w, offset=rep(0, N),
train_params=params, var_monotone=c(0, 0, 0), keep_gbm_data=TRUE, cv_folds=5, is_verbose=FALSE)
best_iter <- gbmt_performance(gbm1, method="test") # returns test set estimate of best number of trees
# make some new data
set.seed(2)
N <- 1000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
f <- 0.5*sin(3*X1 + 5*X2^2 + mu/10) # -0.5 <= f <= 0.5 via sin fn.
tt.surv <- rexp(N,exp(f))
tt.cens <- rexp(N,0.5)
data2 <- data.frame(tt=apply(cbind(tt.surv,tt.cens),1,min),
delta=as.numeric(tt.surv <= tt.cens),
f=f,
X1=X1,X2=X2,X3=X3)
# predict on the new data using "best" number of trees
# f.predict will be on the canonical scale (logit,log,etc.)
f.predict <- predict(gbm1, data2, best_iter)
#plot(data2$f,f.predict)
# Use observed sd
expect_true(sd(data2$f - f.predict) < 0.4)
})
test_that("coxph - runs to completion with train_fraction of 1.0", {
## Needed packages
require(survival)
# Given data from the survival data
# keep only certain baseline variables, subjects with longitudinal data
temp <- subset(pbc, id%in%pbcseq$id, select=c(id:sex, stage))
pbc1 <- tmerge(data1=temp, data2=temp, id=id, death = event(time, status))
pbc2 <- tmerge(pbc1, pbcseq, id=id, ascites = tdc(day, ascites),
bili = tdc(day, bili), albumin = tdc(day, albumin),
protime = tdc(day, protime), alk.phos = tdc(day, alk.phos))
# Training params
params_1 <- training_params(interaction_depth = 3, num_train=round(1.0 * nrow(pbc)), num_trees = 500, id=seq(nrow(pbc)),
shrinkage=.01)
params_2 <- training_params(interaction_depth = 3, num_train=round(1.0 * nrow(pbc2)), num_trees = 500, id=seq(nrow(pbc2)),
shrinkage=.01)
# Then expect no errors when performing gbm fit with train_fraction = 1.0
# GBM fit baseline data
expect_error(gbmt(Surv(time, status==2) ~ bili + protime + albumin + alk.phos, data=pbc,
distribution=gbm_dist("CoxPH"), train_params=params_1), NA)
# GBM fit using start/stop times to get time-dependent covariates
expect_error(gbmt(Surv(tstart, tstop, death==2) ~ bili + protime + albumin + alk.phos,
data=pbc2, distribution=gbm_dist("CoxPH"), train_params=params_2), NA)
})
test_that("coxph - runs to completion with train_fraction < 1.0 and cv_folds > 1", {
## Needed packages
require(survival)
# Given data from the survival data
# keep only certain baseline variables, subjects with longitudinal data
temp <- subset(pbc, id%in%pbcseq$id, select=c(id:sex, stage))
pbc1 <- tmerge(data1=temp, data2=temp, id=id, death = event(time, status))
pbc2 <- tmerge(pbc1, pbcseq, id=id, ascites = tdc(day, ascites),
bili = tdc(day, bili), albumin = tdc(day, albumin),
protime = tdc(day, protime), alk.phos = tdc(day, alk.phos))
# Training params
params_1 <- training_params(interaction_depth = 3, num_train=round(0.8 * nrow(pbc)), num_trees = 500, id=seq(nrow(pbc)),
shrinkage=.01)
params_2 <- training_params(interaction_depth = 3, num_train=round(0.8 * nrow(pbc2)), num_trees = 500, id=seq(nrow(pbc2)),
shrinkage=.01)
# Then expect no errors when performing gbm fit with train_fraction < 1.0 and cv_folds > 1
# GBM fit baseline data
expect_error(gbmt(Surv(time, status==2) ~ bili + protime + albumin + alk.phos, data=pbc, distribution=gbm_dist("CoxPH"),
train_params=params_1), NA)
expect_error(gbmt(Surv(time, status==2) ~ bili + protime + albumin + alk.phos, data=pbc, distribution=gbm_dist("CoxPH"),
train_params=params_1, cv_folds=5), NA)
# GBM fit using start/stop times to get time-dependent covariates
expect_error(gbmt(Surv(tstart, tstop, death==2) ~ bili + protime + albumin + alk.phos,
data=pbc2, distribution=gbm_dist("CoxPH"), train_params=params_2), NA)
expect_error(gbmt(Surv(tstart, tstop, death==2) ~ bili + protime + albumin + alk.phos,
data=pbc2, distribution=gbm_dist("CoxPH"), train_params=params_2, cv_folds=5), NA)
})
test_that("coxph cv_folds - runs to completion with start-stop, id'ed and stratified dataset", {
## Needed packages
require(survival)
# Given data from the survival package
cgd2 <- cgd[cgd$enum==1,]
# Training params
params_1 <- training_params(interaction_depth = 1, num_train=nrow(cgd2), num_trees = 500, id=seq(nrow(cgd2)),
shrinkage=.01)
params_2 <- training_params(interaction_depth = 1, num_train=round(0.8 * nrow(cgd2)), num_trees = 500, id=seq(nrow(cgd2)),
shrinkage=.01)
params_3 <- training_params(interaction_depth = 3, num_train=round(1.0 * length(unique(cgd$id))), num_trees = 500, id=cgd$id,
shrinkage=.01)
params_4 <- training_params(interaction_depth = 3, num_train=round(0.8 * length(unique(cgd$id))), num_trees = 500, id=cgd$id,
shrinkage=.01)
# Then fitting a gbm model should throw no errors - with cv_folds > 1
expect_error(gbmt(Surv(tstop, status) ~ age + sex + inherit +
steroids + propylac + hos.cat, data=cgd2,
distribution = gbm_dist("CoxPH"), train_params=params_1, cv_folds=10), NA)
expect_error(gbmt(Surv(tstop, status) ~ age + sex + inherit +
steroids + propylac + hos.cat, data=cgd2,
distribution = gbm_dist("CoxPH"), train_params=params_2, cv_folds=5), NA)
expect_error(gbmt(Surv(tstart, tstop, status) ~ age + sex + inherit +
steroids + propylac, data=cgd,
distribution = gbm_dist("CoxPH", strata=cgd$hos.cat), train_params=params_3, cv_folds=10), NA)
expect_error(gbmt(Surv(tstart, tstop, status) ~ age + sex + inherit +
steroids + propylac, data=cgd,
distribution = gbm_dist("CoxPH", strata=cgd$hos.cat), train_params=params_4, cv_folds=10), NA)
})
test_that("bernoulli works", {
skip_on_cran()
set.seed(1)
# create some data
N <- 1000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
p <- 1/(1+exp(-(sin(3*X1) - 4*X2 + mu)))
Y <- rbinom(N,1,p)
# random weights if you want to experiment with them
w <- rexp(N)
w <- N*w/sum(w)
data <- data.frame(Y=Y,X1=X1,X2=X2,X3=X3)
offset <- rep(0, N)
# Set up for new API
params <- training_params(num_trees=3000, interaction_depth=3, min_num_obs_in_node=10,
shrinkage=0.001, bag_fraction=0.5, id=seq(nrow(data)), num_train=N/2, num_features=3)
dist <- gbm_dist("Bernoulli")
fit <- gbmt(Y~X1+X2+X3, data=data, distribution=dist, weights=w, offset=offset,
train_params=params, var_monotone=c(0, 0, 0), keep_gbm_data=TRUE, cv_folds=5, is_verbose = FALSE)
best_iter <- gbmt_performance(fit, method="test") # returns test set estimate of best number of trees
# make some new data
set.seed(2)
N <- 1000
X1 <- runif(N)
X2 <- runif(N)
X3 <- factor(sample(letters[1:4],N,replace=T))
mu <- c(-1,0,1,2)[as.numeric(X3)]
p <- 1/(1+exp(-(sin(3*X1) - 4*X2 + mu)))
Y <- rbinom(N,1,p)
data2 <- data.frame(Y=Y,X1=X1,X2=X2,X3=X3)
# predict on the new data using "best" number of trees
# f.predict will be on the canonical scale (logit,log,etc.)
f.1.predict <- predict(fit, data2, n.trees=best_iter)
# compute quantity prior to transformation
f.new = sin(3*X1) - 4*X2 + mu
# Base the validation tests on observed discrepancies
expect_true(sd(f.new - f.1.predict) < 1.0)
})
test_that("relative influence picks out true predictors", {
skip_on_cran()
set.seed(1234)
X1 <- matrix(nrow=1000, ncol=50)
X1 <- apply(X1, 2, function(x) rnorm(1000)) # Random noise
X2 <- matrix(nrow=1000, ncol=5)
X2 <- apply(X2, 2, function(x) c(rnorm(500), rnorm(500, 3))) # Real predictors
cls <- rep(c(0, 1), ea=500) # Class
X <- data.frame(cbind(X1, X2, cls))
# Construct model
params <- training_params(num_trees=1000, interaction_depth=2, min_num_obs_in_node=10,
shrinkage=0.01, bag_fraction=0.5, id=seq(1000), num_train=1000, num_features=55)
dist <- gbm_dist("Bernoulli")
fit <- gbmt(cls~ ., data=X, distribution=dist, weights=rep(1, 1000), offset=rep(0, 1000),
train_params=params, keep_gbm_data=TRUE, cv_folds=5, is_verbose = FALSE)
# Check can get out real predictors
ri <- relative_influence(fit, rescale=TRUE, sort_it=TRUE)
wh <- names(ri)[1:5]
res <- sum(wh %in% paste("V", 51:55, sep = ""))
expect_equal(res, 5)
})
test_that("Conversion of 2 factor Y is successful", {
NumY <- sample(c(0, 1), size=1000, replace=TRUE)
FactY = factor(ifelse(NumY==1, "Yes", "No"), levels=c("No", "Yes"))
PredX <-
data.frame(
x1 = runif(1000)
,x2 = runif(1000)
)
# Fit 1 - Rel Influence
set.seed(32479)
params <- training_params(num_trees=50, interaction_depth=3, min_num_obs_in_node=10,
shrinkage=0.001, bag_fraction=0.5, id=seq(1000), num_train=1000, num_features=2)
g1 <- gbmt(y ~ ., data = data.frame(y = NumY, PredX)
, distribution = gbm_dist("Bernoulli"), train_params=params, is_verbose = FALSE)
rig1 <- relative_influence(g1, num_trees=50)
# Fit 2 - Rel Influence
set.seed(32479)
g2 <- gbmt(y ~ ., data = data.frame(y = FactY, PredX)
, distribution = gbm_dist("Bernoulli"), train_params=params, is_verbose = FALSE)
rig2 <- relative_influence(g2, num_trees=50)
expect_equal(rig1, rig2)
})
test_that("Cross Validations group generation - Bernoulli", {
NumY <- sample(rep(c(0,1), 500), size=1000)
NumX <- matrix(rep(0, size=1000), nrow=1000, ncol=1)
dist <- gbm_dist("Bernoulli")
data <- gbm_data(NumX, NumY, weights=rep(1, length=1000), offset=rep(0, length=1000))
cv_groups <- create_cv_groups(data, dist, training_params(num_train=1000, id=1:1000, num_features=1),
cv_folds=4, cv_class_stratify=FALSE, fold_id=NULL)
expect_true(all(table(cv_groups)==250))
cv_stratified <- create_cv_groups(data, dist, training_params(num_train=1000, id=1:1000, num_features=1),
cv_folds=4, cv_class_stratify=TRUE, fold_id=NULL)
Strats <- sapply(1:4, function(x){table(NumY[cv_stratified == 1])})
expect_true(all(Strats == 125))
})
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