How to use maps to improve insight in Tableau?
Using Maps to Improve Insight
In our time, when men have looked upon the Earth from afar, seeing it as a small, glistening sphere spinning in the black sea of space, it requires a long backward flight of imagination to appreciate the earlier perception of the Earth. There were visions of wonder and myth, and often they were marvelously wrong.
– JOHN WILFORD
The tableau is designed to make the most of geographical data, so you can get to the “where” as well as the “why.” With instant geocoding, Tableau automatically turns the location information you already have into rich, interactive maps with 16 levels of zoom—or use custom geocodes to map what matters to your business. Census-based population, income, and other demographics are built in. In the visual environment of Tableau, you can explore the world through data and share what you find in just a few clicks.
People are accustomed to using maps to find places, predict the weather and see information regarding world events. Seeing your data displayed on a map can provide new insight. Tableau provides three standard map formats. If you don’t like the standard maps, you can replace them with customized maps provided by web mapping services. Or, if you have spatial data that is too small to fit on a map, you can replace maps with images.
If you have a connection to the web, Tableau’s standard maps provide very granular geographic details. Alternatively, if you don’t have an available Internet connection, Tableau allows you to change to locally-rendered offline maps, building Maps Quickly with Show Me.
If your data includes geographic information, you can create a map visualization in less than five seconds by double-clicking on any geographic dimension (denoted by the globe icon), then double-clicking on any measure. When you do this, Tableau will place three pills on the appropriate shelves and present you with a map view of your data with the measures placed at the center of the geographic unit you selected. Tableau provides two different map types for displaying data; symbol maps and filled maps. Symbol maps place marks at specific geographic center points. Filled style map color-encode the geographic shapes using a measure or dimension to apply the fill. Tableau also provides three map background image styles:
- Normal— Off-white land forms with blue water
- Gray— Gray land forms with white water
- Dark— Dark gray land forms with light gray water
If you do not need to make a clear distinction between land and water forms, you will find that the gray map style places more emphasis on your data. The dark map style can be particularly useful if you have to project maps on an older overhead projector. Try different appearance options by going to the map menu, then selecting Map Options. From there, you can change the map style, alter the washout of the map background, or apply map layers. Tableau includes map layers that add more geographic details (base, land cover, roads) and United States census data. If you want to save your map option selections for later use, click the Make Default button at the bottom of the menu.