1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
|
library(caret)
context('Testing varImp')
test_that('glmnet varImp returns non-negative values', {
skip_on_cran()
skip_if_not_installed('glmnet')
set.seed(1)
dat <- SLC14_1(200)
reg <- train(y ~ ., data = dat,
method = "glmnet",
tuneGrid = data.frame(lambda = .1, alpha = .5),
trControl = trainControl(method = "none"))
# this checks that some coefficients are negative
coefs <- predict(reg$finalModel, s=0.1, type="coef")
expect_lt(0, sum(0 > coefs))
# now check that all elements of varImp are nonnegative,
# in spite of negative coefficients
vis <- varImp(reg, s=0.1, scale=F)$importance
expect_true(all(vis >= 0))
})
|
