Book Image

Hands-On Data Preprocessing in Python

By : Roy Jafari
5 (2)
Book Image

Hands-On Data Preprocessing in Python

5 (2)
By: Roy Jafari

Overview of this book

Hands-On Data Preprocessing is a primer on the best data cleaning and preprocessing techniques, written by an expert who’s developed college-level courses on data preprocessing and related subjects. With this book, you’ll be equipped with the optimum data preprocessing techniques from multiple perspectives, ensuring that you get the best possible insights from your data. You'll learn about different technical and analytical aspects of data preprocessing – data collection, data cleaning, data integration, data reduction, and data transformation – and get to grips with implementing them using the open source Python programming environment. The hands-on examples and easy-to-follow chapters will help you gain a comprehensive articulation of data preprocessing, its whys and hows, and identify opportunities where data analytics could lead to more effective decision making. As you progress through the chapters, you’ll also understand the role of data management systems and technologies for effective analytics and how to use APIs to pull data. By the end of this Python data preprocessing book, you'll be able to use Python to read, manipulate, and analyze data; perform data cleaning, integration, reduction, and transformation techniques, and handle outliers or missing values to effectively prepare data for analytic tools.
Table of Contents (24 chapters)
1
Part 1:Technical Needs
6
Part 2: Analytic Goals
11
Part 3: The Preprocessing
18
Part 4: Case Studies

Chapter 11: Data Cleaning Level III – Missing Values, Outliers, and Errors

In level I, we cleaned up the table without paying attention to the data structure or the recorded values. In level II, our attention was to have a data structure that would support our analytic goal, but we still didn't pay much attention to the correctness or appropriateness of the recorded values. That is the objective of data cleaning level III. In data cleaning level III, we will focus on the recorded values and will take measures to make sure that three matters regarding the values recorded in the data are addressed. First, we will make sure missing values in the data have been detected, that we know why this has happened, and that appropriate measures have been taken to address them. Second, we will ensure that we have taken appropriate measures so that the recorded values are correct. Third, we will ascertain that the extreme points in the data have been detected and appropriate measures...