Chris McMahan

The Professionals Cohort (South Carolina)

Christopher McMahan (South Carolina)

About Chris:

I am an Associate Professor in the School of Mathematical and Statistical Sciences at Clemson University. As a statistician, my research interests include developing diagnostic testing strategies and infectious disease modeling.

At the onset of the COVID-19 pandemic, I joined an interdisciplinary public health team that was tasked with devising, evaluating, and operationalizing various mitigation strategies to slow the spread of COVID-19 at Clemson University.

I completed my Bachelor’s degree majoring in mathematics, minoring in physics, at Austin Peay State University, Clarksville, TN.

I then earned a master’s degree in mathematics at Western Kentucky University, Bowling Green, Kentucky. I then completed a doctoral degree in statistics at the University of South Carolina, Columbia, SC.

After completing my Ph.D., I joined Clemson University as an assistant professor, and I was recently promoted to the rank of associate. In addition to my teaching responsibilities, I also consult with Biorealm and serve as a Visiting Professor at BINUS University.

My research interests include, but are not limited to, categorical data analysis, group testing, survival data analysis, nonparametric methods, measurement error models, spatio-temporal modeling, statistical computing, Bayesian parametric/nonparametric estimation, high dimensional regression techniques, epidemiology/public health, and biomedical applications.

A few words from those who nominated Chris:

“Dr. McMahan is a statistician at Clemson University where he has used his skillset to help keep our community safe. He helped develop and implement a novel surveillance-based informative testing strategy for SARS-CoV-2 detection. That strategy and the continuous work he has done to improve the models has allowed our University to safely remain open. Dr. McMahan has mentored several graduate students, preparing them to lead the next pandemic, and cares deeply about their growth. He is a voice of reason – calm and collected – never seeking credit – but responsible for so much of our success. Chris has become a close friend and I feel very lucky to have gotten to know him over this past year. He and his wife have brought my family several meals while we were struggling with a cancer diagnosis. He reaches out to us constantly. In short, he continually has stepped up in the continuous crises that all of us have experienced since the beginning of the pandemic. He is a data hero.”

Click here to see the Clemson University COVID-19 Dashboard

Lior Rennert

The Specialists Cohort (South Carolina)

From the Greenville Journal:

Lior Rennert (South Carolina)

Throughout the COVID-19 pandemicLior Rennert has been knee-deep in researching the best ways to study the spread of the novel coronavirus in order to mitigate its reach. 

Rennert, assistant professor in Clemson’s department of public health sciences and a biostatistician, is leading a significant part of the university’s response to COVID-19.

Last fall, Rennert and his team decided to look into pre-arrival testing before students came back to campus.

“We essentially developed models that showed that if you test everybody before arrival or upon arrival, you can severely limit the outbreak size and delay them as well,” says Rennert. He says that he gives Clemson credit for conducting pre-arrival testing even though the Centers for Disease Control and Prevention had yet to explicitly recommend it.

Another aspect of planning against the coronavirus focused on what Rennert calls a new “surveillance-based informative testing” strategy — research currently under peer-review. Through random testing, the university identified hot spots in residence halls ​and targeted their testing resources to test these students. Such targeted tests were twice as likely to detect positive cases compared to random tests, ​which allowed university officials to quickly act to isolate and quarantine students and help stem the spread of the virus.

“It was really effective,” Rennert says. “It drove down prevalence by almost 40% over a two-week implementation period.”

Dr. Rennert’s ‘Tasks’:

  1. Leading modeling efforts at Clemson University (along with Christopher McMahan and Corey Kalbaugh) to evaluate and implement testing strategies for mitigation of SARS-CoV-2 spread
  2. Implemented surveillance-based informative testing on the university campus, where I would monitor Covid-19 prevalence on campus and direct testing resources to residence halls experiencing outbreaks
    2. Manuscript detailing this strategy accepted for publication at The Lancet Child and Adolescent Health (link to come in next 7-10 days)
  3. Directing Clemson’s Covid-19 dashboard
  4. Working with South Carolina health systems and departments of health to efficiently allocate vaccines to underserved communities (using data-driven models)

A few words from those who nominated Lior:

“Dr. Rennert is a biostatistician at Clemson University where he has used his skillset to help keep our community safe. He helped develop and implement a novel surveillance-based informative testing strategy for SARS-CoV-2 detection. That strategy and the continuous work he has done to improve the models has allowed our University to safely remain open. At the same time, Dr. Rennert has been a critical voice to our statewide vaccine rollout. He has developed models to help increase the equitable distribution of vaccines in SC. I am an epidemiologist and I credit Lior with helping to keep me positive during what has been an incredibly challenging year for my profession. Personally, he has become a close friend and I am really lucky to get to work with such a thoughtful and kind person. He cares about others well-being above his own and represents the best of what we can be as public health professionals. He is a data hero to all of us in SC.”

Click here to see the Clemson University COVID-19 Dashboard

Philip Nelson

The Newcomers Cohort (South Carolina)

Philip Nelson (South Carolina)

Since the beginning of the COVID-19 pandemic, Philip Nelson has collected data and informed South Carolinians about the virus in their state.

In March 2020, Nelson started a simple spreadsheet to collect daily data, but then quickly realized that he could use his computer science background to automate his work and expand the resources he provided.

Starting off, he didn’t know much about working with data or using code, but over time that changed.

He wrote scripts and learned to use data tools and libraries to help visualize the data, and then he started posting the information to his Twitter.

Over several months he learned how to use programming to pull large amounts of data from SC DHEC, visualize it, and then post it to twitter all within seconds of the data going live.

His work has garnered attention from state legislators. local media, and public health researchers.

“I care about accurately presenting the data in an accessible manner, and I want everyone to have access to data,” Nelson said. “Because DHEC doesn’t accessibly provide downloadable case history for the state and its counties, I provide CSVs and graphs of this data on my website.”

Philip has worked hard and learned many things in order to become a reliable source for South Carolina COVID19 data.

A few words from those who nominated Philip:

“As an investigative reporter his datasets have provided me leads on stories I wasn’t even thinking about, particularly the scale of COVID outbreak in South Carolina prisons. His willingness to push through and find new ways of analyzing data particularly in a rural southern state is unlike anything else I’ve seen.”

“I’m a retired biostatistician. When the pandemic hit, I started tracking SCDHEC data on my own. As soon as I found Philip’s data tracking, I quit doing my own. Philip posts summaries, points out trends, and presents it all in clear graphics, usually within minutes of SCDHEC’s daily data release. He points out inconsistencies in the official data, and does a better job than SCDHEC explaining the quirks in data collection. He does all this on his own time, while a full-time student at Winthrop. He has a knack for digging into data and turning it into user-friendly graphics, and the drive to get through the many technical issues of automating the process. He has a bright future ahead.”

Click here to follow Philip on Twitter