Book Image

CompTIA Data+: DAO-001 Certification Guide

By : Cameron Dodd
Book Image

CompTIA Data+: DAO-001 Certification Guide

By: Cameron Dodd

Overview of this book

The CompTIA Data+ certification exam not only helps validate a skill set required to enter one of the fastest-growing fields in the world, but also is starting to standardize the language and concepts within the field. However, there’s a lot of conflicting information and a lack of existing resources about the topics covered in this exam, and even professionals working in data analytics may need a study guide to help them pass on their first attempt. The CompTIA Data + (DAO-001) Certification Guide will give you a solid understanding of how to prepare, analyze, and report data for better insights. You’ll get an introduction to Data+ certification exam format to begin with, and then quickly dive into preparing data. You'll learn about collecting, cleaning, and processing data along with data wrangling and manipulation. As you progress, you’ll cover data analysis topics such as types of analysis, common techniques, hypothesis techniques, and statistical analysis, before tackling data reporting, common visualizations, and data governance. All the knowledge you've gained throughout the book will be tested with the mock tests that appear in the final chapters. By the end of this book, you’ll be ready to pass the Data+ exam with confidence and take the next step in your career.
Table of Contents (24 chapters)
1
Part 1: Preparing Data
7
Part 2: Analyzing Data
13
Part 3: Reporting Data
19
Part 4: Mock Exams

Calculating correlations

There are many different versions of correlation analysis, but they all do the same basic thing and you will not be required to distinguish between them. Before we jump into talking about correlation analysis, let’s take a moment to discuss the concept of correlation in a broader sense.

Correlation

A correlation is simply a relationship between two variables. If there is a relationship, it can be positive or negative. Earlier, in Chapter 6, Types of Analytics, we discussed using scatter plots to get a general idea about these relationships. Let’s use them as illustrations now. In Figure 10.9, we see what a positive correlation looks like:

Figure 10.9 – Positive correlation

Figure 10.9 – Positive correlation

A positive correlation means that as one variable increases, so does the other. This means that the dots form a loose line from the lower left to the upper right. For example, there is a positive correlation between the number of...