4: Getting started with statistics

Introduction to statistics

You can uncover a great deal of information by applying the data aggregation and visualization techniques you’ve explored so far; but to really understand the relationships in the data, you need to apply some statistical analysis. Statistics is at the heart of data science, so in this lesson we’ll explore some basic statistical principles and calculations.

Note: The goal of this course is to familiarize you with the foundational concepts and techniques used in data science - this lesson is not intended to be a deep-dive into statistics, but rather a simple first step into the fascinating world of statistical analysis. In some topics, statistics are shown as mathematical formulae, because that’s typically how professional data scientists express them; but don’t be intimidated by the strange symbols and language - focus on understanding the core concepts.

In this lesson, you’ll learn how to:

• Measure central tendency to find typical values
• Measure variance to determine how different your data values are from one another
• Determine data distributions, to understand the “spread” of your data
• Work with samples, and use statistics to extrapolate relationships in samples to the full population of data.
• Measure correlation between numeric data values
• Use a hypothesis test to validate the probability of perceived relationships in your data