Book Image

Data Science with Python

By : Rohan Chopra, Aaron England, Mohamed Noordeen Alaudeen
Book Image

Data Science with Python

By: Rohan Chopra, Aaron England, Mohamed Noordeen Alaudeen

Overview of this book

Data Science with Python begins by introducing you to data science and teaches you to install the packages you need to create a data science coding environment. You will learn three major techniques in machine learning: unsupervised learning, supervised learning, and reinforcement learning. You will also explore basic classification and regression techniques, such as support vector machines, decision trees, and logistic regression. As you make your way through the book, you will understand the basic functions, data structures, and syntax of the Python language that are used to handle large datasets with ease. You will learn about NumPy and pandas libraries for matrix calculations and data manipulation, discover how to use Matplotlib to create highly customizable visualizations, and apply the boosting algorithm XGBoost to make predictions. In the concluding chapters, you will explore convolutional neural networks (CNNs), deep learning algorithms used to predict what is in an image. You will also understand how to feed human sentences to a neural network, make the model process contextual information, and create human language processing systems to predict the outcome. By the end of this book, you will be able to understand and implement any new data science algorithm and have the confidence to experiment with tools or libraries other than those covered in the book.
Table of Contents (10 chapters)

Boosting Algorithms

Boosting is a way to improve the accuracy of any learning algorithm. Boosting works by combining rough, high-level rules into a single prediction that is more accurate than any single rule. Iteratively, a subset of the training dataset is ingested into a "weak" algorithm to generate a weak model. These weak models are then combined to form the final prediction. Two of the most effective boosting algorithms are gradient boosting machine and XGBoost.

Gradient Boosting Machine (GBM)

GBM makes use of classification trees as the weak algorithm. The results are generated by improving estimations from these weak models using a differentiable loss function. The model fits consecutive trees by considering the net loss of the previous trees; therefore, each tree is partially present in the final solution. Hence, boosting trees decreases the speed of the algorithm, and the transparency that they provide gives much better results. The GBM algorithm has a lot of parameters...