Book Image

Python Data Analysis - Third Edition

By : Avinash Navlani, Ivan Idris
5 (1)
Book Image

Python Data Analysis - Third Edition

5 (1)
By: Avinash Navlani, Ivan Idris

Overview of this book

Data analysis enables you to generate value from small and big data by discovering new patterns and trends, and Python is one of the most popular tools for analyzing a wide variety of data. With this book, you’ll get up and running using Python for data analysis by exploring the different phases and methodologies used in data analysis and learning how to use modern libraries from the Python ecosystem to create efficient data pipelines. Starting with the essential statistical and data analysis fundamentals using Python, you’ll perform complex data analysis and modeling, data manipulation, data cleaning, and data visualization using easy-to-follow examples. You’ll then understand how to conduct time series analysis and signal processing using ARMA models. As you advance, you’ll get to grips with smart processing and data analytics using machine learning algorithms such as regression, classification, Principal Component Analysis (PCA), and clustering. In the concluding chapters, you’ll work on real-world examples to analyze textual and image data using natural language processing (NLP) and image analytics techniques, respectively. Finally, the book will demonstrate parallel computing using Dask. By the end of this data analysis book, you’ll be equipped with the skills you need to prepare data for analysis and create meaningful data visualizations for forecasting values from data.
Table of Contents (20 chapters)
Section 1: Foundation for Data Analysis
Section 2: Exploratory Data Analysis and Data Cleaning
Section 3: Deep Dive into Machine Learning
Section 4: NLP, Image Analytics, and Parallel Computing

Stemming and lemmatization

Stemming is another step in text analysis for normalization at the language level. The stemming process replaces a word with its root word. It chops off the prefixes and suffixes. For example, the word connect is the root word for connecting, connected, and connection. All the mentioned words have a common root: connect. Such differences between word spellings make it difficult to analyze text data.

Lemmatization is another type of lexicon normalization, which converts a word into its root word. It is closely related to stemming. The main difference is that lemmatization considers the context of the word while normalization is performed, but stemmer doesn't consider the contextual knowledge of the word. Lemmatization is more sophisticated than a stemmer. For example, the word "geese" lemmatizes as "goose." Lemmatization reduces words to their valid lemma using a dictionary. Lemmatization considers the part of speech near the words for...