## FIELD NOTE: Your Math is All Wrong…

At the request of a friend, I recently reviewed the article “Your Math Is All Wrong: Flipping The 80/20 Rule For Analytics” by John Thuma. It is a good article, but incomplete and bit misguided. Thuma argues that we are spending too much time in preparing data (prepping) and not enough time analyzing it.  The illusion of the article is that he will “reveal” the magic needed to solve this problem at the end. Spoiler… he does not.

I agree with the premise; that is, a disproportionate amount of time is spent in data prepping (80%), but the author does not provide any insights into how to reduce it (the flip from 80% to 20%). Study after study has show this to be the case, so it is worthless to argue a statistical point. But towards the end of the article, he states that, “Flipping the rule will mean more data-driven decisions.” Ok, I get it. But please explain how?

Well, the cheap “naive” way would be to just start spending more time with the analytics process itself. That is, once the prep process is complete, just spend 16x more effort with analytics (do the math). This would give you the 20% prep and 80% analytics the author wants to achieve. Cheep trick, but that is statistics. But even that is not the issue. The real issue isn’t moving from 80% to 20%.

The real is challenge is understanding exactly what “value” means in the data science process and understanding a systematic way to achieve it. In the end, if I have to spend 80% of time preparing and 20% analyzing in order to discover “how” to grown a business in a profitable way, who cares what the ratio is. Real value comes for focusing on the questions; from what (descriptive), to why (diagnostic), to when (predictive), and finally how (prescriptive). In doing so, a chain is created with each stage linking value (AKA a value chain). Ok, but how do you do this?

Addressing that question (my reveal) is beyond the scope of this article. I would suggest one start by looking at a few article in Data Scientist Insights blog. There are several articles that deal exactly on this point. After that, write me (@InsightDataSci) and we can talk.

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