One of the most interesting features of Tableau is its capability to understand your geographical data like Longitude & Latitude, Country, Stage, Country, Post Code etc. and plot data as filled maps (or choropleths) or symbols on a map at a desired (and available) level of geographical granularity. However, what makes this much more interesting and elevates this ability to Geospatial Intelligence is the ability to overlay Maps with Data Layers that help correlate important demographic data with the data being analysed.
The Data Layer functionality can be accessed by choosing the “Tableau Classic” Maps option as shown below:
Then, clicking on “Map Options” brings up the Maps pane on the left hand side and allows the user to control the features displayed on the map, color / style of the Map etc. and also choose a Data Layer to include, if so desired, as shown below:
Aha! This now helps you analyse your Metrics in relation to the median “Household Effective Buying Income” at a County level and makes your analysis that much more nuanced. But what if you wanted to let he user analyse the same data, but in relation to the expected Population Growth over the next 5 years in each County?
Tableau does not provide any default way of toggling among the various Data Layers on the fly on the dashboard itself. To achieve this, you need to create two separate maps and then Show/Hide one of them based on the user’s choice. This can be achieved quite easily using Parameter controls and the Horizontal Container in Tableau. The steps are as below:
- Pull a horizontal container into the dashboard
- Create a map worksheet with the Household Income data layer
- Duplicate the map worksheet and change the data layer to Population Growth
- Pull both maps into the horizontal container and hide the titles
Now both maps are available in the dashboard, and what is remaining is to set up functionality to let the user toggle between the two.
- Set up a Data Overlay Parameter with the 2 data layer options – Household Income and Population Growth
- Create a Calculated Field “Data Overlay” that is equal to the Data Overlay parameter.
- Navigate to the Household Income map worksheet, add the Data Overlay Parameter and choose Household Income; then filter the map worksheet by Data Overlay calculated field = Household Income.
- Repeat the above step for the Population Growth map worksheet.
- Add the Data Overlay parameter to the dashboard.
The user can now toggle between the two Data Layers using a simple dropdown, as shown below.
The same process can be followed for more demographic data layers like Per Capita Income, Male/Female Ratio, % of Asian Population etc. In the example above, we have also allowed the user to toggle the Metric visualized by the Symbols on the map (size and color of circles) so that he has a comprehensive geospatial intelligence environment that allows for each important Measure available in the data to be correlated with each either Household Income or Population Growth.
Do let us know if this blog post has turbo-charged your geospatial analysis and helped derive better insights from your data 🙂
This blog is written by Farid Jalal, Analytics Project Manager at BRIDGEi2i
About BRIDGEi2i: BRIDGEi2i provides Business Analytics Solutions to enterprises globally, enabling them to achieve accelerated business impact harnessing the power of data. Our analytics services and technology solutions enable business managers to consume more meaningful information from big data, generate actionable insights from complex business problems and make data driven decisions across pan-enterprise processes to create sustainable business impact. To know more visit www.bridgei2i.com
The views and opinions expressed in this article are those of the author and do not necessarily reflect the official position or viewpoint of BRIDGEi2i.