Data Visualization Basics

Overview

Time: 15 min

Objectives

• To get a fundamental grasp of data visualization.

• The audience will be introduced to the tableau platform in general, as well as basic charts and visualizations in tableau.

1. What is Data Visualization?

• Data visualization is a way of representing the data in the form of graphs, maps or charts. Pictorial representation of data helps in identifying trends or patterns in data as well as outliers in the data.
• What makes data visualization so special is that it squeezes a large amount of data in just one graph.

1. Why Data Visualization?

Data Visualization helps in data interpretation in the most efficient way possible. The history of data visualization goes back to the 17th century where maps and graphs were used to understand the data better. One notable example of it is the map of Napoleon’s invasion of Russia. The map depicted the size of the army as well as the path of Napoleon’s retreat from Moscow – and tied that information to temperature and time scales for a more in-depth understanding of the event.

Advantages of using Data Visualization –

• Human brain is a powerful processor and vision dominates our memory. Hence data visualization helps the audience retain the information for a long time.
• A picture is worth a thousand words. With massive amount of data being generated every day, Data visualization helps to tell stories by curating data into a form which is easier to understand.
• Identifying trends in data seems like an obvious use of data visualization, but it is kind of an important one. To make predictions, we need data from past and present. Trends over time tell us how a firm is doing and how a firm can potentially go.
• Not only does it help in predicting future occurrences,it also helps in identifying current areas that need attention/improvements.

3.Good / Bad Visualizations

• There are many ways in which data visualization can go wrong. A good visualization is the one where you can find the insights just in a glance.

• It should be simple, easy on the eyes and informative and should avoid visual clutter. Any unnecessary ink on the chart, too much information in one chart, a lot of colors and shapes they all cause visual clutter. Here are some examples of good / bad visualizations –

• Bad Visualizations: a. The pie chart below adds up to a total of 193% which is wrong

b. Too much information in one graph

c. The x-axis scale is not consistent

Good Visualizations: Simple, easy on the eyes and informative graphs

Key Points

• Introduction to Tableau Desktop, Tableau Basics explained in subsequent lessons.