May 27, 2016

Homeless Veterans





Idea for this visualization came from this article about the plight of US veterans with misconduct discharge.  The article mentions about the research that shows US veterans returning from Afghanistan and Iraq with general misconduct discharge have highest risk of becoming homeless, comparing to other discharge categories. 


This study is significant because it highlights the contradiction between the reality where the number of US soldiers discharged with misconduct is increasing and the federal government priority to end homelessness among veterans!  Let’s hope the federal policy will be amended to match the reality so that the veterans can receive some help. 



(Some of you might wonder if the veterans who were discharged with misconduct deserve to have benefits from the government as other veterans?  Maybe or maybe not.  But if the question were rephrased as “Do veterans who were deployed multiple times and served in combat but were discharged with misconduct deserve to have benefits from the government as other veterans?”, would that change your opinion?)


May 6, 2016

How To Create Action Filter on Worksheet with Top N Parameter




I’m pleased to present the inaugural post of a ‘How To’ series, with the intention to share the endless Tableau tricks and tips.  This post will explain the nuances of how to create an action filter on a worksheet where there’s a top N parameter.


For reference on how to filter for top and top N, please review this excellent video from Tableau that shows how INDEX() function is used for ranking.  However, in the video, top N is selected as a fixed number. 


To take this one step further where top N is a parameter, I used Superstore data to create this visualization.  Here’re the steps:


1) Create a ‘Top N Customers’ parameter.


2) Create a calculated field ‘Rank’ using INDEX() function to rank for top N customers.


3) Create a ‘Top N Filter’ calculated field where [Rank] <= [Top N Customers] to show top N customers.


4) Drag the ‘Top N Filter’ to filter pane and select ‘True’.


5) Click on ‘Edit Table Calculation’, in ‘Compute using’, select Advanced.  Move State and Customer over to Addressing pane.  Under Sort, select ‘Field’ and select ‘Profit/Sales’ calculated field. Then click OK to exit ‘Advanced’ window.




6) Back in ‘Edit Table Calculation’ window, select ‘Customer’ in ‘At the level’ and ‘State’ in ‘Restarting every’.  This will calculate at the customer level and restart for every state.




Since the map will be used as a filter, it’s important to make sure that every state is visible.  I decided to go with the hexagonal tile map (read Matt Chambers’ post for instruction).


The last step is to create an action filter where clicking on a state will show the top N customers by profit or sales for that state.