See-through MicroStrategy (playing with transparencies)

One thing that I like about MicroStrategy is the ability to create Web documents. Nowadays self-service discovery technologies (being based on Flash or HTML5) tend to constrain a little the “creative” side of the data analysis: trading off the ease of use for a quite limited set of tools to picture your data. Boundaries are build and it is difficult to bend the rules.

Web documents do not have such restrictions and -in fact- are almost limitless in possibilities. Think about the HTML container that allows us to insert custom HTML/JavaScript, or the image container.

I believe that Business Intelligence is about information as much as about design, and -surely enough- a nice looking dashboard is always preferable to a boring dull one.

A fundamental aspect of modern day web pages is the CSS Opacity / Transparency, so why not using it in a dashboard to spicy it up? The components and widget that come with MicroStrategy allow a very limited use of “No Fill” in the background: you can create a transparent Chart or Panel, but not a transparent rectangle. So I simply created a series of white PNGs with different alpha values that I can insert on top of a background picture to simulate a see-through rectangle.

Then I downloaded a background picture on Flickr (careful with the CC license…) and removed the main panel of a blank dashboard.

You can see the result here, where a Web document turns to A Whiter Shade Of Pale.

now you see me now you dont

You can download the transparent pngs here.

Average of Averages… no, seriuosly.

Tom, Bill and Sandra have one euro each; they go and buy some fruits.

Tom  buys 3 apples for 1€. Bill buys 2 oranges for 1€ and Sandra buys a coconut for 1€.
Tom says “apples cost 0,33 euro cents on average”.
Bill “oranges are 0,50 euro cents on average”
Sandra “coconuts are 1 euro on average”

What is the overall average price of fruits ?

I have seen more than once calculating this as:

0.33 + 0.50 + 1 = 1.83
1.83 / 3 = 0.61

Now, you are a Business Intelligence professional: imagine your customer asking you to calculate an average, such as the price per product grouped by product type and the total overall price per product at company level.
Next he dig into his laptop and proudly shows off his “treasure” Excel sheet that does it all, and by magic copy and paste computes the AVG() of the AVG()…

Unfortunately for your client, acrobatic math is not yet an Olympic discipline.

Tom, Bill and Sandra soon realize that they bought 3 + 2 + 1 = 6 pieces of fruit and they spent 3€, so a single piece is 0,50 euro cents.

Similarly your customer (after an intense discussion) will realize that for the last 15 years he used to calculate a price per product average “from a different point of view”. You may want to ease the pain by saying that it is a quite common error and he’s in good company: see Simpson’s paradox and the Berkeley gender bias case

In MicroStrategy terms this is what is called a “Smart Metric”.

When in the Metric Editor, switch to the Subtotals / Aggregation tab, down to the left there’s a check box that you can enable to surprise your customer… cool.

How to Lie with Statistics (by Darrell Huff)

I just finished reading this 140 paperback about statistics, and I found it enlightening:
How to Lie with Statistics: Written by Darrell Huff, 1993 Edition, (Reissue) Publisher: W. W. Norton & Company [Paperback]

It was written back in 1954, but the topics it covers are timeless, and -not surprisingly- Mr Huff has few very useful tips applicable to nowadays business intelligence. You can only tell that the text is 60 years old when looking at the details: in one example there is the price of a good hotel room in San Francisco (an eye popping figure: 8$).

One of the first Chapters explains the “biased sample” problem, which affects so many scientific results; another one points the finger to an old trick used to convey distorted messages with line graphs. Many of the wrongdoings he exposes, sounds hard to believe, are still in use today, and you can find plenty of them in ads, magazines, and (sadly) in government polls. Not earlier than one month ago, one very famous cable news network was showing a chart picturing an “impressive” improvement in Spanish unemployment rate: from 26% down to 22% (ouch!). It was something like this:


What they failed to show was data from preceding years:


data source: Spain Unemployment Rate 1976-2015

One of my favorite part is when Mr Huff shows how unions or entrepreneurs give inconsistent (to say the least) results from the same set of data. Or how “experts” sum percentages in an mind bending attempt to rewrite the math rules: “buy any 20 products, wait one year, see their price increase by 5%, so overall the cost of life (20 x 5% = 100%) has doubled in one year…”.

Oh, one last point: don’t forget to read the exhilarating story about the rabbit burger…