Zack A. Goodman


Here I showcase things I love to do including data science, projects, cycling and triathlon, writing, and photography.

Connect with me:

When you meet someone new, don’t ask "What do you do?" It limits what people share about themselves to a job description.

Instead, try "What do you love to do?" It ignites curiosity and invites people to express their distinctive interests.

— Adam Grant

Data Science and Causal Inference

We all know that correlation does not imply causation. But what if you need to know how much X causes Y, for example:

I would love to use my causal inference expertise to help you answer these questions and more. Connect with me, and let's chat through approaches that will allow you to know why something happens.

Other consulting services I offer include:

Select Publications

Before becoming a data science consultant, I served as the research lead at Recidiviz uncovering how technology can improve outcomes for justice-involved individuals. Before joining Recidiviz, I completed my PhD in Economics at UC San Diego where I studied how learning technologies impact exam performance and how taxes and stimulus payments affect food choice. Below are links to my papers and replication code repositories.

The Effect of Supplementary Videos on Learning in Microeconomics (with Melissa Famulari)

Can we help our struggling students by assigning them supplementary video-based lectures? See project

The Effect of the Cook County Sweetened Beverage Tax on Nutrient Purchases (with Jacob Orchard)

Do beverage taxes reduce sugar consumption? See project

The Effect of the 2008 Economic Stimulus Payments on Nutrient Demand

How do stimulus payments affect the foods we buy? See project

New paper

Coming soon!


Real cost of travel

Some assume that the change in exchange rates is enough information to tell where in the world it is cheaper or more expensive to travel...

However, exchange rates often move with local inflation, making it challenging to tell how much real exchange rates have changed for visitors of foreign countries. In this notebook, I use publicly available data to generate a history of real cost of living in one's home currency for nearly every country in the world.

Can you guess the most and least affordable countries to travel to?


GPSRace started as a collaboration with my brother, Justin Goodman, to help cyclists compete safely and equitably during the pandemic...

As the easiest way to host a race with zero overhead and very little time required, the site hosted over 150 races across the world. We have elected to turn off hosting to save costs, but please contact me if you would like to use the site!

When the pandemic started, many cyclists turned to virtual methods to continue competing. Conventional "virtual races" are location agnostic: racers are required to complete a set distance anywhere in the world. While this is convenient, it destroys the legitimacy of the results since the course itself plays an enormous role in finish time.

Our solution? Use GPS data to determine completion times on the same course. GPSRace works as follows:

Besides encouraging social distancing, GPSRace adds a second safety feature to races: neutral segments. Time accrued during neutral segments does not count towards overall time, allowing race organizers to neutralize roads with lots of traffic, stop lights, and stop signs.

By creating this platform, we hope to enable races that wouldn't otherwise happen and ultimately encourage more cyclist to join the sport. Eventually, we plan to support running and triathlon as well.

Next project

Coming soon!

Cycling and Triathlon

Paratriathlon Guiding

Paratriathlon, for visually-impaired (VI) athletes, is a team sport. VI athletes compete alongside a guide (affectionately, a "seeing-eye human") who completes the swim and run while tethered to the athlete and the bike using a tandem. I've written about my experience guiding and how it works on Quora and in this Q&A with UCSD Club Sports.

I've been fortunate to work with several talented VI paratriathletes, most introduced to me by San Diego-based elite paratriathlete Amy Dixon through her Camp No Sight No Limits. Through the 2024 season, I'll be racing on the USA Paratriathlon National Team with Kyle Coon. Kyle is 2020 Paralympian currently training for the 2024 Paralympics in Paris. Check out Kyle's blog - here's his post about our first international win at World Paratriathlon Series Yokohama, pictured left.


Everesting is climbing the elevation of Mount Everest (29,029') on your bike, on the same hill, in the one ride - most cyclists' definition of type II fun.

I decided to Everest in part thanks to the "Swift Sourdough Seekers" challenge hosted by San Diego-based pro cyclist Robin Carpenter. By completing the most repeats on Mount Soledad and ascending the most elevation in a single ride, I earned two loaves of Robin's famous homemade sourdough.

Ironman Triathlon

An Ironman triathlon is a race consisting of a 2.4 mile swim, 112 mile bike, and 26.2 mile run. I completed my first in 2018 at Ironman Canada. Later that year, I won my age group at Ironman Maryland, qualifying the for the 2019 World Championships in Kona, Hawaii (pictured left). In 2023, I completed Ironman California as a guide for Corvin Bazgan.

I'm currently taking a break from long distance racing to focus on paratriathlon guiding, which is predominantly sprint distance (750M swim, 20K bike, 5K run).

Biking across the USA

Between undergrad and grad school, I biked from Ocean City, WA to Ocean City, MD starting at the Pacific Ocean and ending in the Atlantic. For the first 2/3 of the trip I followed the Adventure Cycling Association's Norther Tier route, after which I meandered my way around the Great Lakes and south towards my home state.

Though I began my ride solo, I met many cyclists along the way, rarely biking by myself for long. I created a compilation video of Snapchats taken during my trip, which you can view to the right.



Pictures speak louder than we need exposition in the photography section?


Sports scenes are constantly changing, and photographers have mere milliseconds to capture the perfect moment. The lack of control over lighting, positioning, and timing forces one to neglect perfection and shoot in the moment - the most thrilling way to spectate an event!

Nature and outdoor portraits

While sports are the most fun to capture, nature is the most beautiful. It's a blessing to live in Southern California where beaches, mountains, cliffs, sunsets, and wildlife are all readily accessible. The bioluminesent red tide in San Diego made for some fun nighttime photography, too.

My photos have been featured in: