Dionne Price

The practice of statistics empowers researchers, policymakers, and individuals to drive innovation, understand complex phenomena, and make informed decisions. However, the public may not fully grasp the transformative power of our profession. To address this knowledge gap, I am delighted to announce the “Telling Our Stories” video project, which aims to highlight the profound impact of statistics and inspire a greater appreciation for its contribution to advancing science and society.

“Telling Our Stories” will feature a series of thought-provoking interviews with expert statisticians—applied and theoretical—as well as scientists, researchers, and experts from diverse disciplines. Each video will delve into real-world examples, demonstrating how statistics has revolutionized fields such as health care, economics, the environmental sciences, technology, and the social sciences. These compelling narratives will showcase how statistical analyses have led to breakthrough discoveries, evidence-based policy-making, and improved decision-making processes, ultimately shaping the fabric of our society. With a global audience in mind, the project aims to make statistics accessible to individuals from all backgrounds. The videos will employ engaging storytelling techniques and visually captivating elements, ensuring viewers not only comprehend the significance of statistical insights but also feel inspired to explore statistical concepts further.

We envision a world in which statistical literacy is embraced, leading to a more informed citizenry capable of critically assessing claims, navigating uncertainties, and contributing to evidence-based decision-making. This project will help us realize our vision by weaving together personal stories and real-life examples. Once the videos are created, they will be available on our website and the social media platforms we use.

This project would not be possible without the generous support of Nan Laird, a trailblazer in our community. Below, I share a recent conversation I had with Nan in which she graciously shared a few of her stories. I am extremely grateful for Nan’s generosity in giving her time, talent, and monetary support.

Nan Laird

Dionne: Your very generous gift will support the “Telling Our Stories” video project. What inspired you to work with the ASA to develop this particular project?

Nan: I was so honored to receive the 2021 International Prize in Statistics. It made me reflect on how lucky I was to have chosen a career that brought me so much joy and fulfillment. The prize came with a substantial monetary amount. I felt I wanted to give back the prize money to educate the public on what statisticians do and how we change their world.

I thought it would be rewarding to work with the ASA to raise the profile of statisticians and the critical role they play in all aspects of society. In particular, 2021 was also the middle of the pandemic. And there wasn’t much you could do except watch the news and read the newspapers. We were just seeing a lot of news where statisticians could weigh in, but we didn’t see many statisticians weighing in, at least in the news I was watching. The other big area we were hearing about was the integrity of elections. And I’m thinking to myself there must be statisticians who know a lot about these subjects. Why aren’t we hearing from them? We need to elevate our voices.

I decided I would like to give back after having had a wonderful career in this profession, starting with hearing statisticians telling stories of what it is we do.

Dionne: Since we’re discussing the storytelling project, would you share one of your statistical stories with us?

Nan: Yes, I’d be happy to share. I have a number, but I think the one that had the biggest impact was my service on the National Research Council Committee on Airliner Cabin Air Quality. This was back in the mid-80s. The early airplanes were designed to constantly draw in outside air as a way of keeping the air cabin fresh. At about that time, the airlines redesigned the planes. The newer planes were not equipped to draw in fresh air; they had to recirculate the air. There was a process for cleaning up the recirculating air, but it really wasn’t adequate for eliminating cigarette smoke. The airlines created special smoking sections to deal with the problem, but these smoking sections were generally located near the galleys, meaning the flight attendants had a particularly heavy exposure. The public and unions representing flight attendants were lobbying Congress to do something about smoking on airplanes. Congress was reluctant to act on this without any evidence concerning air cabin quality, so a National Academies committee was charged with investigating whether the existing air quality standards were adequate.

There were 11 of us on this panel. I was the only statistician; others included an epidemiologist, medical doctors, occupational health and safety experts, and airplane engineers. It was a diverse group of people looking at air quality. We looked at a tremendous number of aspects, but one of the things we did that I think was most crucial was to consider the exposure of the crew to cigarette smoke and how it might affect the health of the crew.

Not surprisingly, there were no direct studies of the impact of side stream smoke on flight attendants, but there were two related epidemiological studies nearing completion. We had the principal investigators of these studies come and talk to us about their results. These were somewhat unique and special studies looking at the health effects of exposure to side stream smoke.

One of the studies I remember clearly involved pairs of spouses. In one pair, one spouse smoked and the other didn’t. In the other pair, neither spouse smoked. These were long-term studies that looked at the incidence of lung cancer, comparing the spouses whose partners smoked to the spouses whose partners did not smoke. They did find a risk ratio of approximately 2. Although a risk ratio of 2 is low, it was clear, and there were consistent signals that being exposed to a pack of cigarettes/day from side stream smoke would lead to increased lung cancer over time. This finding coupled with the fact that we made measurements and calculations of the amount of exposure the air cabin crew was exposed to and found they were exposed to about the equivalent of a pack/day of side stream smoke.

On this basis, we recommended that smoking be banned from airplanes. This was a huge boost in terms of helping the anti-smoking on airplane groups move forward and to get Congress to enact a ban, first for two years on short flights of less than two hours. Then the ban was extended to all flights within the United States and, ultimately, to international flights, as well.

As a statistician, why was I there? I was there because one of the things I was interested in was meta-analysis. We didn’t do a formal meta-analysis because there wasn’t enough data. It was more of a question of assessing the validity of the literature available that might bear. I don’t claim to have single-handedly eliminated smoking on airplanes, but I was a member of a team that had a tremendous impact. In-depth knowledge of statistics is not required to be impressed by the impact of this work. Many people remember what it was like to travel on airplanes before the smoking ban and are especially grateful for this work.

Dionne: One of the goals of “Telling Our Stories” is to raise public awareness about the impact of statistics and data science. What do you hope the public learns about our profession from this project?

Nan: What I hope they learn is how vital statistics and statisticians are to their daily lives. I also want to encourage statisticians to learn how to effectively tell their stories. I know many do, but we need many more.

I think there are several other areas besides the ones we’ve already mentioned—just emerging areas of research—where statistics plays a big role. For example, climate change. A lot of people do not understand the climate is changing. Statisticians surely have something to say about that. Statisticians have had a lot to say about the effects of environmental exposures on health, and that leads quite naturally to the issues surrounding climate change.

Social justice is another field people are so interested in, and statisticians are in a great position to make important contributions.

The stories don’t necessarily need to be told by statisticians. There are plenty of nonstatisticians who understand all too well the central role statistics plays in their own research.

There’s a wonderful TED talk [“Why Smart Statistics Are the Key to Fighting Crime”] by a former attorney general of New Jersey [Anne Milgram]. She talks about how she used statistics to reform the criminal justice system there. It’s a wonderful TED talk, and I would encourage everyone who wants to try and explain why statistics is important to watch it.

Another emerging area is aging. Now, many of us who are already there are interested in how to stay active and healthy. There are also the effects of an aging population on society. I’m sure statisticians have a lot to contribute.

Dionne: This quote was part of the announcement for the International Prize in Statistics: “The 2021 International Prize in Statistics has been awarded to US biostatistician Nan Laird, Harvey Feinberg Professor of Biostatistics emeritus at Harvard Chan School of Public Health, in recognition of her work on powerful methods that have made possible the analysis of complex longitudinal studies.” Can you tell us how you became interested in this work?

Nan: The work I did on longitudinal studies stemmed from a long and productive collaboration I had with Jim Ware. I joined the biostatistics faculty in 1975 fresh from my PhD. A few years later, Jim Ware joined the faculty, and we became close colleagues and friends, even though we had somewhat different backgrounds. I worked on random effects models for two-way contingency tables, which evolved into working on the EM algorithm. Jim had been at the NIH [National Institutes of Health] working on growth data. He came to Harvard to work with the Harvard Six Cities of Air Pollution and Health, an ongoing study comparing long-term health outcomes of people living in cities with different air pollution profiles.

There were many age groups and health outcomes being studied. One area of focus for Jim was the hypothesis that living in a highly polluted city could impair growth in lung function in children. This was difficult because the design of the study was highly unbalanced for this endpoint. The sample design specified repeated annual sampling of classrooms in schools, but taking measurements of all individual students present on that day. Besides the incompleteness in the data, there were many adjustments needed—for example, age, height, and sex. Jim invited me to collaborate on working out how general linear mixed models could be used to analyze the data. Jim was aware of my work on the EM algorithm and general linear mixed models, so he asked me to consult on the Six Cities Study.

I spent a number of years engaged in that work. They were wonderful years; Jim and I were a good pair. Jim had a very good understanding of the tools practicing statisticians were using to analyze these types of data, and I was more focused on methods. We worked closely and went on to consider related issues, developed a course we co-taught with Garrett Fitzmaurice, and then published a popular text on the subject.

It was a wonderful project. The Six Cities study was a tremendous success in terms of showing the effects of air pollution in many areas. We were not able to show any effects of air pollution on the growth of lung function in children. I think we do not know if it was the design of the study, the analysis, [or] the absence of any effect.

Dionne: Your stories are inspirational to me, Nan, because some of the work you’ve done has become part of the curriculum in many graduate programs. This has been a real honor for me, because I’ve read your work, your papers, as a graduate student, and incorporated some of it into my dissertation.

During our conversation, what really affected me is how your work has been motivated by real-world problems.

Thank you!

Nan: I’m thrilled the ASA is doing this. I think it’s a wonderful project and I’m sure it will go a long way.