Christian Testa

The first offering of ID529 Data Management and Analytic Workflows in R at Harvard

Teaching ID529 was such a blast, and I’m so happy with how the course turned out. The students have repeatedly communicated that they learned an extraordinary amount, that the skills they learned will be tools and frameworks of thinking they take forward with them as they continue their research and scholarship, and that they appreciated the down-to-earth, fun, affirmative atmosphere we fostered in our classroom.

The first offering of ID529 Data Management and Analytic Workflows in R at Harvard feature image

Relationship of political ideology of US federal and state elected officials and key COVID pandemic outcomes

Now that our paper is out in the Lancet Regional Health Americas, I wanted to write up a blog post talking about it.

Relationship of political ideology of US federal and state elected officials and key COVID pandemic outcomes feature image Photo Credit: Figure 2 from our paper

The Public Health Disparities Geocoding Project 2.0

The Public Health Disparities Geocoding Project 2.0 was a workshop where my colleagues and I trained 150 Public Health professionals from diverse backgrounds (city and state health departments, advocacy organizations, policy think-tanks, academia, non-profits, etc.) on how to use geo-referenced data for analyses that promote health equity.

The Public Health Disparities Geocoding Project 2.0 feature image Photo Credit: The Cover of the PHDGP2.0 Training Manual

2021 in Review

I couldn’t really talk about 2021 without mentioning that I got married in June 2021!

2021 in Review feature image Photo Credit: Tamara Kohno,

Boston Night Skyline

I just wanted to share this really nice photo I took of the Boston skyline in the last couple weeks.


Boston Night Skyline feature image Photo Credit: My own photo; check out more on my Unsplash page!

Simulation, Error, and Modeling the Physical World

A few years ago I took a course from Sauro Succi called Computational Methods for the Physical Sciences that surveyed topics such as computational methods for solving partial differential equations

Simulation, Error, and Modeling the Physical World feature image Photo Credit: My own work; a simulation of a normal distribution drifting across periodic boundaries.

Intro to Gaussian Processes

In this article I'm going to try to provide some intuition around how multivariate Gaussian distributions and Gaussian process models can be useful for modeling smooth functions.

Intro to Gaussian Processes feature image Photo Credit: A 2-dimensional sample from a Gaussian process model, Robert Gramacy, Surrogates

HOPE 2020

HOPE 2020 took place July 25th through August 2nd and for the first time ever was all-online due to the COVID-19 pandemic. I’ve written up this summary of my seven favorite talks with some links to read more about their content matter.

National Zoo, 2018

These are just a handful of the shots I thought turned out best from a trip I took down to Washington DC in 2018. Besides visiting the National Zoo, I danced at the DC DanceSport Inferno (DCDI) hosted at the University of Maryland while I was in town and it was great to catch up with a friend that’s been going to law school at Georgetown. We also managed to sneak in a little trip to the Hirshhorn Modern Art Museum.

National Zoo, 2018 feature image Photo Credit: Photographer - Myself, Subject - Red Panda

Resources for R Programmers

This is a set of resources for people interested in the R programming language.

I have designed it with the intention and hope that it will be useful to people of all skill levels from completely new to programming to subject matter experts who might be interested in expanding their horizons.

Every link below is completely free to use.

QualtricsTools : Automated Survey Processing

QualtricsTools is an open source application built in R Shiny that I started while working at Tufts that allows users to upload a Qualtrics JSON QSF Survey File, and response data in CSV format and automatically calculate tables and frequencies custom to the survey’s questions types, format, and responses.

Introduction to the Theory of Elliptic Curves

Elliptic curves are a subject, simple to construct and ubiquitous, that have found themselves at the forefront of Number Theory and Algebraic Geometry research. The subject has roots in some of the oldest Mathematics, and its modern connections tie it to an incredible span of research including fluid flow, sphere packing, modular forms, and string theory. Elliptic curves are the degree three nonsingular algebraic plane curves with at least one rational point.

Their existence was considered by Diophantus in the 2nd century a.d. in his text Arithmetica. The question he originally posed has been rephrased in modern language: “To divide a given number into two numbers such that their product is a cube minus its side.” That is, given $a \in \mathbb N$ find $x,y \in \mathbb Z$ such that \(y(a-y) = x^3 - x.\)

Washington State Photography

In 2016 I visited Washington state, including Seattle, Olympic National Park, and Olympic National Forest. The mist and fog hanging over the roads through the mountains and forest on the way to Olympic National Park made the experience calm and tranquil. The beach was beautiful, bright blue with tide pools and anemone. The stacks of hard rock carved away by the tide coming in and out create a beautiful ocean and beach landscape, with a consistently interesting horizon to fall in love with. Seattle had a very fun culture to appreciate, from plenty of art museums, graffiti, monuments, and history. Absolutely check out the beautiful art at the Chihuly glass museum if you get the chance. It is phenomenal and impressive. I would love to visit Washington state again, and the first item on my agenda would be getting back to Olympic National Park.

Washington State Photography feature image

Colorado State Photography

I went to Colorado in the summer of 2016 and found some heart-moving and serene photography opportunities. I spent time in Denver, Boulder, and, of course, the Rocky Mountain National Park. I struggle to imagine a more picturesque photography experience than that with the brazen elk right next to the road and the incredible and towering mountain ranges spanning the park. The sense of peace that I could derive from spending time in the park is a memory that will always motivate my desire to spend more time in nature. I truly enjoyed my time in Colorado, and I recommend that anybody with an interest in the outdoors find the time to enjoy the beautiful scenery there.

Colorado State Photography feature image