Hands-On Data Visualization

Chapter 7. Map Your Data

Maps draw your readers into data that includes a spatial dimension, while also developing a stronger sense of place. Seeing the relative distance between points on a map, or identifying geographic patterns in a choropleth map (where colored polygons represent data values), relays information to readers’ eyes more effectively than text, tables, or charts. But creating meaningful maps that draw our attention to key insights in your data requires clear thinking about design choices.

In this chapter, we will examine principles of map design and distinguish between good and bad maps in “Map Design Principles”. You’ll learn about rules that apply to all maps, and specific guidelines for creating choropleth maps. While many tools allow you to download maps as static images, our book also demonstrates how to construct interactive charts that invite readers to zoom in and explore the data in their web browsers. In Chapter 9, you’ll learn how to embed interactive charts on your website.

Decisions about map types are based on two main factors: the format of your data, and the kind of story you wish to tell. Learn about different types of maps you can create in this book in Table 7-1. For example, point maps work best to show specific locations with colored markers to represent categories (such as hospitals), while choropleth maps are best suited to display relative values for regions (such as birth rates across US states). After selecting your map type, follow our ...