Book Image

Statistics for Machine Learning

By : Pratap Dangeti
Book Image

Statistics for Machine Learning

By: Pratap Dangeti

Overview of this book

Complex statistics in machine learning worry a lot of developers. Knowing statistics helps you build strong machine learning models that are optimized for a given problem statement. This book will teach you all it takes to perform the complex statistical computations that are required for machine learning. You will gain information on the statistics behind supervised learning, unsupervised learning, reinforcement learning, and more. You will see real-world examples that discuss the statistical side of machine learning and familiarize yourself with it. You will come across programs for performing tasks such as modeling, parameter fitting, regression, classification, density collection, working with vectors, matrices, and more. By the end of the book, you will have mastered the statistics required for machine learning and will be able to apply your new skills to any sort of industry problem.
Table of Contents (16 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Extreme gradient boosting - XGBoost classifier


XGBoost is the new algorithm developed in 2014 by Tianqi Chen based on the Gradient boosting principles. It has created a storm in the data science community since its inception. XGBoost has been developed with both deep consideration in terms of system optimization and principles in machine learning. The goal of the library is to push the extremes of the computation limits of machines to provide scalable, portable, and accurate results:

# Xgboost Classifier
>>> import xgboost as xgb
>>> xgb_fit = xgb.XGBClassifier(max_depth=2, n_estimators=5000, 
learning_rate=0.05)
>>> xgb_fit.fit(x_train, y_train)

>>> print ("\nXGBoost - Train Confusion Matrix\n\n",pd.crosstab(y_train, xgb_fit.predict(x_train),rownames = ["Actuall"],colnames = ["Predicted"]))     
>>> print ("\nXGBoost - Train accuracy",round(accuracy_score(y_train, xgb_fit.predict(x_train)),3))
>>> print ("\nXGBoost  - Train Classification...