Predict Method for Learners

Extends the generic stats::predict() with a method for Learner. Note that this function is intended as glue code to be used in third party packages. We recommend to work with the Learner directly, i.e. calling learner$predict() or learner$predict_newdata() directly.

Performs the following steps:

• Sets additional hyperparameters passed to this function.

• Creates a Prediction object by calling learner$predict_newdata().

• Returns (subset of) Prediction.

Usage

# S3 method for class 'Learner'
predict(object, newdata, predict_type = NULL, ...)

Arguments

object

(Learner)
Any Learner.

newdata

(data.frame())
New data to predict on.

predict_type

(character(1))
The predict type to return. Set to <Prediction> to retrieve the complete Prediction object. If set to NULL (default), the first predict type for the respective class of the Learner as stored in mlr_reflections is used.

...

(any)
Hyperparameters to pass down to the Learner.

Examples

task = tsk("spam")

learner = lrn("classif.rpart", predict_type = "prob")
learner$train(task)
predict(learner, task$data(1:3), predict_type = "response")
#> [1] spam spam spam
#> Levels: spam nonspam
predict(learner, task$data(1:3), predict_type = "prob")
#>           spam    nonspam
#> [1,] 0.8513514 0.14864865
#> [2,] 0.9339623 0.06603774
#> [3,] 0.9339623 0.06603774
predict(learner, task$data(1:3), predict_type = "<Prediction>")
#> <PredictionClassif> for 3 observations:
#>  row_ids truth response prob.spam prob.nonspam
#>        1  spam     spam 0.8513514   0.14864865
#>        2  spam     spam 0.9339623   0.06603774
#>        3  spam     spam 0.9339623   0.06603774