5 Ways to do YoY and YTD –

YoY and YTD – 5 Ways YoY and YTD calculations are fundamental business metric – after all who doesn't want to know how they compared to last year, last month or how they are tracking on a year to date basis.  It seems that users at all experience levels have questions on how to complete […]

Zero to Zen and 5 Stops Along the Way

Zero to Zen covers the 5 foundational concepts I needed to learn on the journey from spreadsheets to Tableau Like many, I struggled when first introduced to Tableau 5 years ago. I don't come from a data scientist background. – Actually, I'm an engineer, very analytic and expert level spreadsheet skills but I just didn't […]

When and How to Scaffold Data

When and How To Use Scaffolds    The data structure has a huge effect on the results you get from your analysis. Like most of you, I trained using well structured and full data sets – where there was a value in every record (cell) – like a tightly fit puzzle  (Note – Presented that the […]

Context filters – What do they really do?

In Tableau, the sequence that filters or calculations are executed is controlled by the Order of Operations – but how does that affect your calculations The order starts with 3 filters – Extract filters limit the data passing from the data source to Tableau, Data Source filters further limit data available in the workbook and […]

Weighted Averages

 Weighted Averages  Lately, there have been a lot of Forum questions about calculating weighted averages  Mathematically, a weighted average is defined as the sum of the individual weights x the values divided by the total of the weights     1 Table Calculation Example   Posters are familiar with how to find weighted averages with a […]

Not all NULLS are created equal

Not all Nulls are created equal? – Really?   Nulls – they break your calculations and mess with your charts but why are they difficult to fix? There are 2  types of nulls each has a different solution Empty Cell Null The easiest to understand and to fix is the Empty Cell Null in your […]

Cannot Mix Aggregate and Non-aggregate

Cannot Mix Aggregate and Non-aggregate  One of the most frequent questions we see on the Forum results from trying mixing aggregate and non-aggregates in the same calculation – But why is that a problem and how do you resolve it –  Next time you load a data file into Tableau, open the data source tab and […]

Use a scaffold to solve the 2 date problem

The most frequently viewed workbook on my Tableau Public site is a solution to the classic 2 date problem.   –   The data have only a start and end date and you need to know how many programs are active on any date – Ultimately you want something like this   The business question can take […]

"How to" Create a Normal Distribution Curve

 How to Create a Normal Distribution Chart  Occasionally there are Forum questions on creating normal distribution curves.        The approach here relies heavily on the concept of data densification develop and refined by Bora Beran, Joe Mako, Jonathan Drummey, Ken Flerlage, and others – Readers are encouraged to review their works on creating shapes and […]