Erik Jensen

Personal Featured

Reflecting on Two and a Half Years at WMATA

To protect folks’ privacy, I’ve avoided using names throughout the post. At the top of every production data pipeline I've written, I print out a Lord of the Rings quote as an Easter Egg for any future developers/analysts who pick up the code. Keeping this tradition

Personal Featured

Falling into Transportation: A Humbling Moment

Between job interviews, coffee chats, and the occasional panel appearance, I’ve told the story of how I got into transportation quite a few times. There’s one detail that I often leave out though, mostly because I haven’t figured out how to weave it in without disrupting the

How-To Featured

Making Population Density Maps with Rayrender in R

On Mastodon recently, I came across some really cool work from @terence@fosstodon.org which used Rayshader in R to create a great population density map of Canada. terence (@terence@fosstodon.org)Attached: 1 image Today’s population density map is Canada. #rayshader adventures, an #rstats taleFosstodon The reason I

Code Featured

The Slow Winding Road to Switching to Linux Full-Time (for Personal Use)

Stepping into my first computer science class in 2012, I was surprised to see a desktop computer and monitor at each seat in the classroom. It was a far cry from classrooms I was used to, and the computers weren't running Windows 7 or OS X Lion. Instead, they were running images of Ubuntu.

Personal Featured

Reflecting on 5+ Years at New York City Transit

I recently left my role at New York City Transit to move to Washington D.C. As part of leaving, I wrote an article for my old department's newsletter, which I've adapted to remove some names/details and republished it.

Personal Featured

Falling in Love with Biking in NYC

If you've met me at some point since I moved to NYC, you might be a bit surprised to learn that I was not a huge fan of biking before moving here. As a kid growing up in the mostly car oriented suburbs (not in NYC), biking was

How-To Featured

Reporting Data 102: Auto-Emailing Reports with Python, MJML, and Gmail

Relying on humans with busy schedules to spend time each day sending recurring emails is going to lead to missed emails and errors. Automate them instead!

Travel Featured

Fall in Pennsylvania

Even though I spent almost the entire summer and Fall in New York City, I ventured into Pennsylvania a couple times to catch up with friends outdoors and get a break from the city.

How-To Featured

Reporting Data 101: Turning around Reports Quickly with RMarkdown and LaTeX

I happen to have a lot of knowledge working in R and LaTeX left over from the days when I thought I would be an academic, so when I needed to automate a weekly report, they fit the bill.

Travel Featured

Exploring Finland via Train and Water

Back in the spring of 2019, I had the opportunity to visit my then fiancée (now wife) in Tampere, Finland. She was living there for a few months working, and I was glad to get the chance to take a week off from work and spend some time with her while exploring the two largest cities.

Personal Featured

A Day in Quarantine Life

Other than the 10 days I spent locked in the bedroom with COVID-19 (0/10, would not recommend), life has settled into an uneventful routine. Here's what it looks like.

Code Featured

Leaving Cmder for Alacritty: 2020 Edition

Since about 2017, I've been using Cmder almost daily as my console emulator of choice. There were a few key reasons why I gravitated towards it, and why it has stuck around for so long, but few issues have now led me elsewhere. Would I still recommend Cmder?

Personal Featured

Working from Home on Minimal Notice

On Sunday, March 15th the governor required all nonessential state employees to work from home, including all of us at the MTA. While the IT department directed employees to use Teams and Webex for remote work, unfortunately the organization also had a fairly active Slack subscription as well...

Theory Featured

Using Checkers to Estimate Free Coffee Rates with Cluster Sampling

After a new city program to promote reading, Taylor ended up in charge of measuring how many people actually brought in books to get their free coffee. While Taylor is not a statistician, they do have a leg up their sleeve.

How-To Featured

How to Scrape WMATA's Real-Time Train and Bus Movement Data

Most large transit agencies have research groups whose full time job it is to analyze operational data, but they often face strict restrictions publishing data. With historic records of real-time data though, academics and nonprofits can perform their own creative analyses.

Transit Featured

Behind the Scenes of Seattle's Transportation Infrastructure

A few weeks ago, I went to Seattle on an exchange program with between the Seattle Chapters of Young Professionals in Transportation (YPT). I was able to go on behind the scenes tour of transportation infrastructure throughout the city.

How-To Featured

Using Parks and Transit in QGIS to Orient Local Readers

A little while back, there was a report from NYCDOT called Bus Forward. While I worked on some of the analysis in the report, one thing I noticed was that the analyst behind the maps included parks, despite them having little to do with bus speeds. Thanks to this report,

Transit Featured

Why Street Patterns can Make or Break Buses

For a couple years in high school I took the DC Metro to the bus to get home. While I often exaggerate the numbers when talking about my commute, even today Citymapper says it would take at least an hour to get home. Because of bus bunching, on a route

How-To Featured

Using pgRouting to Calculate Transit Catchment Areas

In order to show the effects of a grid vs loop and lollipop road network, I downloaded the GTFS files for Ride On bus here. These are simply txt files, with routes, stops, schedule information, and some other details. For this visualization, I also needed a routable network loaded into

Transport Featured

Streetmix, A Street Section Builder for Activists and Professionals Alike

Back in 2013, San Fransisco's Department of Public Works wanted to find ways to facilitate public feedback for the Second Street Improvement Project. Traditionally, planners have used paper cutouts and drawings to get feedback from the public, but this is time consuming, not very flexible, and makes it

Personal Featured

Photos from the Chihuly Exhibit at the Bronx Botanical Gardens

A couple of weekends ago, my girlfriend and I went to the Bronx Botanical Gardens. At the time, there was a Chihuly special exhibit which we wanted to check out. The two of us got on the Subway and took a 4 train up to Bedford Park Blvd. Station. Most

How-To Featured

Setting Up Scoop as a Windows Package Manager

MacOS has Homebrew. Linux has APT. Windows sort of has OneGet. I dual-boot Linux on my desktop, but unfortunately that doesn't seem too feasible on my Surface Book. Since there's a whole bunch of software that is difficult to keep up to date (think 7-Zip), I

Research Featured

Access to Banking Services in Washington D.C.

As I spoke about a little bit in a previous post, inadequate access to savings tools is a classic example of a poverty trap. Without basic banking services, smoothing consumption levels and preparing for emergencies is far more difficult. Income levels differ drastically across Washington D.C., which should hopefully

Transport Featured

A Rainy Earth Day in NYC

Last Saturday (April 22nd, 2017) was Earth Day, and the NYC Department of Transportation (DOT) set up a whole bunch of events here all across the city. I took a Citi Bike to 45th Street and started walking down Broadway. DOT closed Broadway all the way from Times Square to

Personal

Say hi to Arwen!

Hi everyone, This isn't a technical post, life has been kind of hectic the last few weeks. I've also spent most of my personal free time playing the fantastic Legend of Zelda: Breath of the Wild. So instead, here are some pictures of my girlfriend'