The mlr package provides a unified interface for supervised and unsupervised machine learning in R, covering task creation, learner configuration, resampling, performance measurement, hyperparameter tuning, and visualization. It supports classification, regression, clustering, survival, and cost-sensitive tasks.

What’s covered#

  • Setup – normalizeFeatures(), createDummyFeatures(), mergeSmallFactorLevels()
  • Task creation – makeClassifTask(), makeRegrTask(), makeClusterTask(), makeSurvTask()
  • Training & testing – makeLearner(), train(), predict(), performance(), listMeasures()
  • Resampling – makeResampleDesc() for CV, LOO, RepCV, bootstrap, and holdout; resample()
  • Refining performance – makeParamSet(), makeTuneControl*(), tuneParams()
  • Configuration – configureMlr() for error handling and output verbosity
  • Feature extraction – filterFeatures() with importance-based selection methods
  • Visualization – plotThreshVsPerf(), plotROCCurves(), plotResiduals()
  • Wrappers – makeDummyFeaturesWrapper(), makeImputeWrapper(), makePreprocWrapper()