Book Image

Julia for Data Science

By : Anshul Joshi
2 (1)
Book Image

Julia for Data Science

2 (1)
By: Anshul Joshi

Overview of this book

Julia is a fast and high performing language that's perfectly suited to data science with a mature package ecosystem and is now feature complete. It is a good tool for a data science practitioner. There was a famous post at Harvard Business Review that Data Scientist is the sexiest job of the 21st century. (https://hbr.org/2012/10/data-scientist-the-sexiest-job-of-the-21st-century). This book will help you get familiarised with Julia's rich ecosystem, which is continuously evolving, allowing you to stay on top of your game. This book contains the essentials of data science and gives a high-level overview of advanced statistics and techniques. You will dive in and will work on generating insights by performing inferential statistics, and will reveal hidden patterns and trends using data mining. This has the practical coverage of statistics and machine learning. You will develop knowledge to build statistical models and machine learning systems in Julia with attractive visualizations. You will then delve into the world of Deep learning in Julia and will understand the framework, Mocha.jl with which you can create artificial neural networks and implement deep learning. This book addresses the challenges of real-world data science problems, including data cleaning, data preparation, inferential statistics, statistical modeling, building high-performance machine learning systems and creating effective visualizations using Julia.
Table of Contents (17 chapters)
Julia for Data Science
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface

Understanding the significance of the P-value


The probability that a null-hypothesis will be rejected even if it is proven true is the p-value. When there is no difference between two measures, then the hypothesis is said to be a null-hypothesis.

For example, if there is a hypothesis that, in the game of football, every player who plays 90 minutes will also score a goal then the null hypothesis would be that there is no relation between the number of minutes played and the goals scored.

Another example would be a hypothesis that a person with blood group A will have higher blood pressure than the person with blood group B. In a null hypothesis, there will be no difference, that is, no relation between the blood type and the pressure.

The significance level is given by (α) and if the p-value is equal or less than it, then the null hypothesis is declared inconsistent or invalid. Such a hypothesis is rejected.

One-tailed and two-tailed test

The following diagram represents the two-tails being used...