Book Image

Applied Supervised Learning with R

By : Karthik Ramasubramanian, Jojo Moolayil
Book Image

Applied Supervised Learning with R

By: Karthik Ramasubramanian, Jojo Moolayil

Overview of this book

R provides excellent visualization features that are essential for exploring data before using it in automated learning. Applied Supervised Learning with R helps you cover the complete process of employing R to develop applications using supervised machine learning algorithms for your business needs. The book starts by helping you develop your analytical thinking to create a problem statement using business inputs and domain research. You will then learn different evaluation metrics that compare various algorithms, and later progress to using these metrics to select the best algorithm for your problem. After finalizing the algorithm you want to use, you will study the hyperparameter optimization technique to fine-tune your set of optimal parameters. The book demonstrates how you can add different regularization terms to avoid overfitting your model. By the end of this book, you will have gained the advanced skills you need for modeling a supervised machine learning algorithm that precisely fulfills your business needs.
Table of Contents (12 chapters)
Applied Supervised Learning with R
Preface

Predictions


We could also get the predictions on the test dataset using the getBMRPredictions function. The two tables in this section show the actual and the predicted labels of a few images represented by the ID column. Observe that the predictions are not perfect, just as we would expect from the relatively low overall accuracy.

Predictions using randomForestSRC:

head(getBMRPredictions(bmr, as.df = TRUE))

Figure 9.13: The actual labels.

Figure 9.14: The predicted labels.

Learners and measures

The getBMRLearners function gives details about the learners used in the benchmark. Information such as hyperparameter and predict-type could be obtained using this function. Similarly, the getBMRMeasures function provides details such as best about the performance measures. The following table shows the details about the measures we used in our benchmark experiment:

getBMRLearners(bmr)

The output is as follows:

## $multilabel.randomForestSRC
## Learner multilabel.randomForestSRC from package randomForestSRC...