Pete Warden’s Monkey Cage post, “Why You Should Never Trust a Data Scientist” (original version from his blog), illustrates one of the biggest challenges facing both consumers and practitioners of data science: the issue of accountability. And while I suspect that Warden—a confessed data scientist himself—was being hyperbolic when choosing the title for his post, I worry that some readers may well take it at face value. So for those who are worried that they really can’t trust a data scientist, I’d like to offer a few reassurances and suggestions.
Data science (sometimes referred to as “data mining”, “big data”, “machine learning”, or “analytics”) has long been subject to criticism from more traditional researchers. Some of these critiques are justified, others less so, but in reality data science has the same baby/bathwater issues as any other approach to research. Its tools can provide tremendous value, but we also need to accept their limitations. Those limitations are far too extensive to get into here, and that’s indicative of the real problem Warden identified: as a data scientist, nobody checks your work, mostly because few of your consumers even understand it.
As a political scientist by training, this was a strange thing to accept when I left the ivory tower (or its Southern equivalent, anyway) last year to do applied research. The reason for a client to hire someone like me is because I know how to do things they don’t, but that also means that they can’t really tell if I’ve done my job correctly. It’s ultimately a leap of faith—the work we do often looks, as one client put it, like “magic.” But that magic can offer big rewards when done properly, because it can provide insights that simply aren’t available any other way.
So for those who could benefit from such insights, here are a few things to look for when deciding whether to trust a data scientist:
- Transparency: Beware the “black box” approach to analysis that’s all too common. Good practitioners will share their methodology when they can, explain why when they can’t, and never use the words, “it’s proprietary,” when they really mean, “I don’t know.”
- Accessibility: The best practitioners are those who help their audience understand what they did and what it means, as much as possible given the audience’s technical sophistication. Not only is it a good sign that that they understand what they’re doing, it will also help you make the most of what they provide.
- Rigor: There are always multiple ways to analyze a “big data” problem, so a good practitioner will try different approaches in the course of a project. This is especially important when using methods that can be opaque, since it’s harder to spot problems along the way.
- Humility: Find someone who will tell you what they don’t know, not just what they do.
These are, of course, fundamental characteristics of good research in any field, and that’s exactly my point. Data science is to data as political science is to politics, in that the approach to research matters as much as the raw material. Identifying meaningful patterns in large datasets is a science, and so my best advice is to find someone who treats it that way.