Category Archives: Professional

Posts not about my personal life.

I, Harlan D. Harris, hereby commit to the pledge. Please stand with me and hold me to it.

It starts:

We, the undersigned, are employees of tech organizations and companies based in the United States. We are engineers, designers, business executives, and others whose jobs include managing or processing data about people. We are choosing to stand in solidarity with Muslim Americans, immigrants, and all people whose lives and livelihoods are threatened by the incoming administration’s proposed data collection policies. We refuse to build a database of people based on their Constitutionally-protected religious beliefs. We refuse to facilitate mass deportations of people the government believes to be undesirable.

(read the rest)

Per the web site, they no longer add signatures to the site, but instead ask people to post a commitment on a personal blog or Twitter, which I have done here.

Patterns for Connecting Predictive Models to Software Products

This was originally published on Medium on June 21st, 2016.

You’re a data scientist, and you’ve got a predictive model — great work! Now what? In many cases, you need to hook it up to some sort of large, complex software product so that users can get access to the predictions. Think of LinkedIn’s People You May Know, which mines your professional graph for unconnected connections, or Hopper’s flight price predictions. Those started out as prototypes on someone’s laptop, and are now running at scale, with many millions of users.

Metaphor (source)

Even if you’re building an internal tool to make a business run better, if you didn’t build the whole app, you’ve got to get the scoring/prediction (as distinct from the fitting/estimation) part of the model connected to a system someone else wrote. In this blog post, I’m going to summarize two methods for doing this that I think are particularly good practices — database mediation and web services.

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Simulating Rent Stabilization Policy at the National Day of Civic Hacking

This post was originally published on Medium on June 5, 2016.

Yesterday was the 2016 National Day of Civic Hacking, a Code for America event that encourages people with technology and related skills to explore projects related to civil society and government. My friend Josh Tauberer wrote a thoughtful post earlier about the event called Why We Hack —on what the value of this sort of event might be — please read it.

For my part, this year I worked on one of the projects he discusses, understanding the impact of DC’s rent stabilization laws and what potential policy changes might yield. As Josh noted, we discovered that it’s a hard problem. Much of the most relevant data (such as the list of properties under rent stabilization and their current and historical rents) are not available, and have to be estimated. Getting to a realistic understanding of the impact of law and policy on rents seems incredibly valuable, but hard.

So I spun off the main group, and worked on an easier but much less ambitious project that could potentially be useful in just an afternoon’s work. Instead of trying to understand the law’s effect on actual DC rents, I built a little tool to understand the law’s effect on a rather unrealistic set of simulated apartment buildings. Importantly, I did this fully aware that I’m not building with, I’m tinkering; my goal was to do something fun and interesting that might lead to something substantial and usable later, probably by someone else.

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Thoughts on Managing Data Science Team Workstreams (and a Shiny app)

This is an updated version of a post originally published on Medium on Jan. 28, 2016. I may have more to say about this sort of thing in the near future.

There are different types of data scientists, with different backgrounds and career paths. With Sean Murphy and Marck Vaisman, I wrote an article about this for O’Reilly a few years back, based on survey research we’d done. Download a copy, if you haven’t read it. This idea is now pretty well established, but I want to talk about a related issue, which is that the type of work that Data Science teams do varies a lot, and that managing those types of work can be an interesting challenge.

As Josh Wills said, data scientists aren’t software developers, but they sometimes do that sort of work, and they aren’t statisticians, but they sometimes do that sort of work too. At EAB, where I lead a Data Science team of people with very diverse backgrounds and skill sets, this issue leads to a lot of complexity and experimentation as we (and the upper management I report to) try to ensure that everyone is working on the right tasks, at the right time, efficiently.

In this post, I’d like to share some thoughts about how we currently think about and manage different types of Data Science work. I also wrote a little Shiny web tool to help us manage our time, and I’ll show that off as well.

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Building a Complementary Data Science Team

This is an updated version of an article first posted on Medium on Nov. 23, 2015. I’ve disabled the links to the jobs, as those specific ones are no longer available. If you’re interested in a role at EAB or the Advisory Board, please get in touch, though!

I’m the Director of Data Science at EAB, a firm that provides best-practices research and enterprise software for colleges and universities. My team is responsible for the predictive models and other advanced analytics that are part of the Student Success Collaborative product that’s used by academic advisors and other campus leadership. We’re hiring data scientists, and I wanted to publicly say a few things about the roles we have advertised. (Note that EAB is part of a public company and is in a competitive market, so there are obviously things I’m not saying!)

The most important point is that data scientists specialize, so look for the specializations. My co-authors and I made this point in our 2012 e-book Analyzing the Analyzers, and the folks at Mango Solutions are burning up Twitter with their self-service tool for identifying data science strengths and weaknesses.

Drew Conway’s Data Science Venn Diagram

A related point is that existing framing devices can help you balance a team. Drew Conway’s Venn Diagram remains a great way to think about Data Science aptitude. Combine people with strengths in each part of the diagram, who know enough to collaborate effective and make each other stronger, and you don’t need a team of unicorns with 3 PhDs each.

I suspect the details of the framing device are less important than the fact that you have one. It forces you to think about variety and complementary skills, and how people work together to solve problems and build systems.

At EAB, we have four career tracks for data scientists — Research, Engineering, Statistical Programming, and Management. Our new roles supplement our existing team by adding several new people, each with different capabilities and seniority.

At a Senior level, we’re looking for a Statistical Programmer-track person who is particularly strong in algorithm development and implementation, perhaps a straight-up Computer Scientist. Think of the “Machine Learning” area in Drew’s diagram. As we look to expand the classes of statistical techniques that we use, we need more people who know the academic literature and can figure out exactly what technical solution will let us build and scale high-quality models. Interested? Please apply!

A little less senior, we’re also looking for a Researcher who can help us apply domain knowledge even more effectively in our analyses, models, and systems. Some software, data visualization, and statistical skills required — maybe a quantitative Social Scientist pivoted into industry? The upper edge of the Substantive Expertise area. Sound like you? Please apply!

I strongly believe that a Data Science team should do all of the Data Science, including building and owning models in production. So, last but not least, we’re looking for another Engineering-focused data scientist, who can help us build model frameworks, data tools, workflow tools, and more. This role can be junior or even entry-level, but we do need programming skills, statistical thinking skills, and some sort of portfolio. Programmer and recent data science boot camp grad, perhaps? Please apply!

Of course, as we talk to people, learn what they’re good at and excited about, and what they bring, we may end up with a different mix of skills. But regardless, they’ll cover the space of data scientists, will provide different perspectives and skills, and will help us own our own tools and systems so that we can move and learn quickly.

Parameterizable Reproducible Research

The below is a public version of a post originally posted on an internal blog at the Education Advisory Board (EAB), my current employer. We don’t yet have a public tech blog, but I got permission to edit and post it here, along with the referenced code. 

Data Science teams get asked to do a lot of different sorts of things. Some of what the team that I’m part of builds is enterprise-scale predictive analytics, such as the Student Risk Model that’s part of the Student Success Collaborative. That’s basically software development with a statistical twist and machine-learning core. Sometimes we get asked to do quick-and-dirty, one-off sorts of things, to answer a research question. We have a variety of tools and processes for that task. But there’s a third category that I want to focus on – frequently requested but slightly-different reports.

what is it

There’s a relatively new theme in the scientific research community called reproducible research. Briefly, the idea is that it should be possible to re-do all steps after data collection automatically, including data cleaning and reformatting, statistical analyses, and even the actual generation of a camera-ready report with charts, graphs, and tables. This means that if you realized that, say, one data point in your analysis was bogus and needed to be removed, you could remove that data point, press a button, and in a minute or two have a shiny new PDF with all of the results automatically updated.

This type of reproducible research has been around for a while, although it’s having a recent resurgence in part due to the so-called “statistical crisis“. The R (and S) statistical programming languages have supported LaTeX, the scientific document creation/typesetting tool, for many years. Using a tool called Sweave, a researcher “weaves” chunks of text and chunks of R code together. The document is then “executed”, where the R code chunks are executed and the results are converted into a single LaTeX document, which is then compiled into a PDF or similar. The code can generate charts and tables, so no manual effort is needed to rebuild a camera-ready document.

This is great, a huge step forward towards validation of often tricky and complex statistical analyses. If you’re writing a conference paper on, say, a biomedical experiment, a reproducible process can drastically improve your ability to be confident in your work. But data scientists often have to generate this sort of thing repeatedly, from different sources of data or with different parameters. And they have to do so efficiently.

Parameterizable reproducible research, then, is a variant of reproducible research tools and workflows where it is easy to specify data sources, options, and parameters to a standardized analytical report, even one that includes statistical or predictive analyses, data manipulation, and graph generation. The report can be emailed or otherwise sent to people, and doesn’t seem as public as, say, a web-based app developed in Shiny or another technology. This isn’t a huge breakthrough or anything, but it’s a useful pattern that seems worth sharing.

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INFORMS Business Analytics 2014 Blog Posts

Earlier this year, I attended the INFORMS Conference on Business Analytics & Operations Research, in Boston. I was asked beforehand if I wanted to be a conference blogger, and for some reason I said I would. This meant I was able to publish posts on the conference’s WordPress web site, and was also obliged to do so!

Here are the five posts that I wrote, along with an excerpt from each. Please click through to read the full pieces:

Operations Research, from the point of view of Data Science

  • more insight, less action — deliverables tend towards predictions and storytelling, versus formal optimization
  • more openness, less big iron — open source software leads to a low-cost, highly flexible approach
  • more scruffy, less neat — data science technologies often come from black-box statistical models, vs. domain-based theory
  • more velocity, smaller projects — a hundred $10K projects beats one $1M project
  • more science, less engineering — both practitioners and methods have different backgrounds
  • more hipsters, less suits — stronger connections to the tech industry than to the boardroom
  • more rockstars, less teams — one person can now (roughly) do everything, in simple cases, for better or worse

What is a “Data Product”?

DJ Patil says “a data product is a product that facilitates an end goal through the use of data.” So, it’s not just an analysis, or a recommendation to executives, or an insight that leads to an improvement to a business process. It’s a visible component of a system. LinkedIn’s People You May Know is viewed by many millions of customers, and it’s based on the complex interactions of the customers themselves.

Healthcare (and not Education) at INFORMS Analytics

[A]s a DC resident, we often hear of “Healthcare and Education” as a linked pair of industries. Both are systems focused on social good, with intertwined government, nonprofit, and for-profit entities, highly distributed management, and (reportedly) huge opportunities for improvement. Aside from MIT Leaders for Global Operations winning the Smith Prize (and a number of shoutouts to academic partners and mentors), there was not a peep from the education sector at tonight’s awards ceremony. Is education, and particularly K-12 and postsecondary education, not amenable to OR techniques or solutions?

What’s Changed at the Practice/Analytics Conference?

In 2011, almost every talk seemed to me to be from a Fortune 500 company, or a large nonprofit, or a consulting firm advising a Fortune 500 company or a large nonprofit. Entrepeneurship around analytics was barely to be seen. This year, there are at least a few talks about Hadoop and iPhone apps and more. Has the cost of deploying advanced analytics substantially dropped?

Why OR/Analytics People Need to Know About Database Technology

It’s worthwhile learning a bit about databases, even if you have no decision-making authority in your organization, and don’t feel like becoming a database administrator (good call). But by getting involved early in the data-collection process, when IT folks are sitting around a table arguing about platform questions, you can get a word in occasionally about the things that matter for analytics — collecting all the data, storing it in a way friendly to later analytics, and so forth.

All in all, I enjoyed blogging the conference, and recommend the practice to others! It’s a great way to organize your thoughts and to summarize and synthesize your experiences.

Why a Data Community is Like a Music Scene — Resources

On Monday, October 28th, 2013, I gave a 5-minute Ignite talk entitled “Why a Data Community is Like a Music Scene” at an event associated with the Strata conference. Here’s the video:

And here are the acknowledgements and references for the talk:

Data Community DC

How Music Works, by David Byrne

my slides for the Ignite talk

my blog post (written first)



More posts on the Data Community DC blog

For those people (or, more likely, 0 or 1 persons) who follow this blog to catch up on my professional thoughts: I’ve been doing a little bit of writing on the Data Community DC blog. Here are all my posts over there: I’d definitely encourage you to read everyone else’s work on the DC2 blog too!

Two titles of my own:

And three  of others’:

There are also weekly round-up posts on data topics generally, and on data visualization specifically, as well as event previews and reviews, etc.


integrating R with other systems

I just returned from the useR! 2012 conference for developers and users of R. One of the common themes to many of the presentations was integration of R-based statistical systems with other systems, be they other programming languages, web systems, or enterprise data systems. Some highlights for me were an update to Rserve that includes 1-stop web services, and a presentation on ESB integration. Although I didn’t see it discussed, the new httr package for easier access to web services is also another outstanding development in integrating R into large-scale systems.

Coincidentally, I just a week or so ago had given a short presentation to the local R Meetup entitled “Annotating Enterprise Data from an R Server.” The topic for the evening was “R in the Enterprise,” and others talked about generating large, automated reports with knitr, and using RPy2 to integrate R into a Python-based web system. I talked about my experiences building and deploying a predictive system, using the corporate database as the common link. Here are the slides: