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)
Part 1: Preparing Data
Part 2: Analyzing Data
Part 3: Reporting Data
Part 4: Mock Exams


This has been a fun chapter and it covered a lot of useful tools. First, we discussed frequencies, which are counts of every possible value, and how to create frequency tables. Then, we discussed percentages as an extension of frequency that describes how the counts affect the whole of the data.

We talked about percent change, which is how a single value changes. It will always have a starting value and an ending value and be told in terms of the starting value. It matters which value is which. With percent change, you can have positive and negative values that correspond to the value increasing or decreasing. Percent difference is not quite the same thing. It describes the objective difference between two values of equal importance. As such, it does not matter which value is which, and it cannot have a negative value.

Confidence intervals describe a range around the mean of your sample distribution. You are confident that the “true mean” of your population...