Can you toolify away the data scientists?

From GigaOM:

Machine learning startup Wise.io, whose founders are University of California, Berkeley, astrophysicists, has raised a $2.5 million series A round of of venture capital. The company claims its software, which was built to analyze telescope imagery, can simplify the process of predicting customer behavior.

And from Wise.io’s website:

Read how one fast growing Internet company turned to Wise to get a Lead Scoring Application, scrapped their plans to hire a Data Scientist and replaced their custom code with an end-to-end Leading scoring Application in a couple of weeks.

Uh oh. Pretty soon no one’s going to hire data scientists!*

[Aside: Editors will still be needed. How about “lead scoring application” instead of “Leading scoring Application?” Heh. Aside to the aside: predictive lead scoring is among the easiest of data science problems currently confronting humans.]

But it’s not that easy to “toolify” data analysis. We need human data scientists for now, because humans are able to:

  • Frame problems
  • Design features
  • Unfool themselves

What we’re talking about here is freestyle data science – humans supported with advanced data science tools. [See: Tyler Cowen on freestyle chess.]

Not just any old humans. Humans who know how to do data science.

Frame problems
Data science projects do not arrive on an analyst’s desk like graduate school data analysis projects, with the question you are supposed to answer given to you. Instead, data scientists work with business experts to identify areas potentially amenable to optimization with data-based approaches. Then the data scientist does the difficult work of turning an intuition about how data might help into a machine learning problem. She formulates decision problems in terms of expected value calculations. She selects machine learning algorithms that may be useful. She figures out what data might be relevant. She gathers it and preps it (see below) and explores it.

Design features
Just as real-world data science projects do not arrive with a neat question and preselected algorithm preformulated, they also do not arrive with variables all prepped and ready. You start with a set of transaction records (or file system full of logs… or text corpus… or image database) and then you think, “O human self, how can I make this mess of numbers and characters and yeses and nos representative of what’s going on in the real world?” You might log-transform or bin currency amounts. You might need to think about time and how to represent changing trends (exponentially weighted moving average?) You might distill your data – mapping countries to regions for example. You might enrich it – gathering firmographics from Dun & Bradstreet.

You also must think about missing values and outliers. Do you ignore them? Impute and replace them? Machines can be given instruction in how to handle these but they may do it crudely, without understanding the problem domain and without being able to investigate why certain values are missing or outlandish.

Unfool themselves
We humans have an uncanny ability to fool ourselves. And in data analysis, it seems easier than ever to do so. We fool ourselves with leakage. We fool ourselves by cross-validating with correlated data. We fool ourselves when we think a just-so story captures truth. We fool ourselves when we think that big data means we can analyze everything and we don’t need to sample.

[Aside: We are always sampling. We sample in time. We sample from confluences of causes. Analyzing all the data that exists doesn’t mean that we have analyzed all the data that a particular data generation mechanism could generate.]

What humans can do is unfool ourselves. Machines cannot do that because they don’t understand the world well enough. How do we do so? By careful thought about the problem domain and questioning of too-good predictive results. With carefully designed observational studies. With carefully designed and executed experiments.

Care: that’s what humans bring to machine learning and machines do not. We care about the problem domain and the question we want to answer. We care about developing meaningful measures of things going on in that domain. We care about ensuring we don’t fool ourselves.

* Even if we can toolify data science and I have no doubt we will move ever towards that, the tool vendors will still need data scientists. I predict continued full employment. But I may be fooling myself. 

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