About

Arnold I. Barnett is the George Eastman Professor of Management Science and a Professor of Statistics at the MIT Sloan School of Management. His research specialty is applied mathematical modeling with a focus on problems of health and safety. Barnett’s early work on homicide was presented to President Gerald Ford at the White House, and his analysis of U.S. casualties in Vietnam was the subject of a column by William F. Buckley. He has written op-ed pieces for major publications including The New York Times, The Wall Street Journal, the Boston Globe, CNN Opinion, the Charlotte Observer, and USA Today. Barnett has received numerous awards, including the President’s Award and the Expository Writing Award from INFORMS, and is a Fellow of INFORMS. Recognized as “the nation’s leading expert on aviation safety,” he was awarded the 2002 President’s Citation from the Flight Safety Foundation for his contributions to safety. He holds a BA in mathematics from Columbia College and a PhD in mathematics from MIT. Barnett has been honored by MIT Sloan students on 14 occasions for outstanding teaching.

Research topics

• Geography
• Sociology
• Engineering
• Demography
• Medicine
• Statistics
• Aeronautics
• Mathematics
• Virology
• Demographic economics
• Economics
• Business
• International trade

Selected publications

• Airline safety: Still getting better?

  Journal of Air Transport Management · 2024-07-13 · 5 citations

  article1st authorCorresponding
  PublisherDOI

• Why did US urban homicide spike in 2020? A cross‐sectional data analysis for the largest American cities

  Risk Analysis · 2024-01-13 · 1 citations

  articleSenior authorCorresponding

  Working with data about homicide victims and perpetrators from 50 of America's largest cities, we investigate the explanatory power of some familiar explanations for why murder in those cities rose sharply in 2020. The analysis reveals that the distribution of risk by race was essentially the same in 2020 as in 2019. That empirical finding challenges some theories of how racial tensions after the death of George Floyd may have driven homicide increases. Similarly, homicide growth was not concentrated in those cities with the greatest availability in 2020 of new and older guns, or among the cities that suffered the most from the COVID-19 pandemic. At a minimum, the cross-city outcomes should reduce confidence that some combination of "race, guns, and COVID-19" explains all of the most important aspects of what happened in 2020.

  PublisherDOI

• The Polls and the U.S. Presidential Election in 2020 …. and 2024

  Statistics and Public Policy · 2023-04-04 · 8 citations

  articleOpen access1st authorCorresponding

  Arguably, the single greatest determinant of US public policy is the identity of the president. And if trusted, polls not only provide forecasts about presidential-election outcomes but can act to shape those outcomes. Looking ahead to the 2024 US presidential election and recognizing that polls before the 2020 presidential election were sharply criticized, we consider whether such harsh assessments are warranted. Initially, we explore whether such polls as processed by the sophisticated aggregator FiveThirtyEight successfully forecast actual 2020 state-by-state outcomes. We evaluate FiveThirtyEight’s forecasts using customized statistical methods not used previously, methods that take account of likely correlations among election outcomes in similar states. We find that, taken together, the pollsters and FiveThirtyEight did an excellent job in predicting who would win in individual states, even those “tipping point” states where forecasting is more difficult. However, we also find that FiveThirtyEight underestimated Donald Trump’s vote shares by state to a modest but statistically significant extent. We further consider how the polls performed when the more primitive aggregator Real Clear Politics combined their results, and then how well single statewide polls performed without aggregation. It emerges that both Real Clear Politics and the individual polls fared surprisingly well.

  PublisherDOI

• Covid-19 infection risk on US domestic airlines

  Health Care Management Science · 2022 · 11 citations

  1st authorCorresponding
  • Demography
  • Geography
  • Medicine

  Working with recent data and research findings, we estimate the probability that an air traveler in economy class would have contracted Covid-19 on a US domestic jet flight over the nine-month period June 2020 to February 2021. The estimates take account of the rates of confirmed Covid-19 infections in the US, flight duration, fraction of seats occupied, and some demographic differences between US air travelers and US citizens as a whole. Based on point estimates, the risk of contracting Covid-19 in-flight exceeded 1 in 1000 on a fully-loaded two-hour flight at the height of the pandemic over the nine months, but was about 1 in 6000 on a half-full flight when the pandemic was at a low ebb. However, these estimates are subject to substantial uncertainty, with the 10th percentiles of various risk distributions only about 1/7 as large as the medians, and the 90th percentiles about four times as large. Based on seat-occupancy levels on US flights for each month over June 2020 to February 2021, the median risk estimate for that period is 1 in 2250, while the mean risk estimate is 1 in 1450. Indirect effects arose because those who contracted Covid-19 on US airplanes could in turn infect others.

  PublisherOA PDFDOI

• A Simple Fix for Gerrymandering?

  CHANCE · 2022-01-02

  article1st authorCorresponding

  Now that the 2020 census results are at hand, there is fear that US state legislatures will engage in partisan mischief to ensure that the dominant political party gets more seats in future elections than is justified by its share of the popular vote. We present an alternative to existing arrangements that would by its very construction eliminate the most glaring consequence of such “gerrymandering,” though the scheme creates another problem. We argue that this problem is considerably less consequential than one might at first fear.

  PublisherDOI

• A Simple Fix for Gerrymandering?

  SSRN Electronic Journal · 2021-01-01

  articleOpen access1st authorCorresponding
  PublisherDOI

• The Meaning of “Intermittency” in Criminal Careers

  Journal of Developmental and Life-Course Criminology · 2020-07-10 · 4 citations

  articleOpen access
  PublisherOA PDFDOI

• Covid-19 Risk Among Airline Passengers: Should the Middle Seat Stay Empty?

  medRxiv (Cold Spring Harbor Laboratory) · 2020 · 35 citations

  1st authorCorresponding
  • Sociology
  • Geography
  • Demography

  Abstract We use recent data and research results to approximate the probability that an air traveler in coach will contract Covid-19 on a US domestic flight two hours long, both when all coach seats are full and when all but middle seats are full. The point estimates we reach based on data from late June 2020 are 1 in 4,300 for full flights and 1 in 7,700 when middle seats are kept empty. These estimates are subject to both quantifiable and nonquantifiable sources of uncertainty, and sustain known margins of error of a factor about 2.5. However, because uncertainties in key parameters affect both risk estimates the same way, they leave the relative risk ratio for “fill all seats” compared to “middle seat open” close to 1.8 (i.e., close to 1/4,300)/(1/7,700). We estimate the mortality risks caused by Covid-19 infections contracted on airplanes, taking into account that infected passengers can in turn infect others. The point estimates—which use 2019 data about the percentage of seats actually occupied on US flights--range from one death per 400,000 passengers to one death per 600,000. These death-risk levels are considerably higher than those associated with plane crashes but comparable to those arising from two hours of everyday activities during the pandemic.

  PublisherOA PDFDOI

• All The Same? On a Certain Pattern in Cross‐National Death Risk

  Risk Analysis · 2020-06-29 · 1 citations

  articleOpen access1st authorCorresponding

  This article considers whether a nation that fares relatively well (or badly) on a particular dimension of mortality risk tends also to do so on others. Working with 2016 data from the Global Burden of Disease (GBD) Study, we focus on six causes of premature death: transport accidents, other accidents, homicide, early-childhood diseases, and both communicable and noncommunicable diseases beyond early childhood. We consider data from all 26 nations that had populations of at least 50 million in 2016, as well as 15 clusters of smaller nations that are similar in longevity (e.g., Scandinavia). We use an analytic method that facilitates useful comparisons across nations, for it recognizes that some potential death risks can be underestimated because citizens die sooner from other causes. We estimate reductions in lifespan from each of the six causes relative to natural lifespan as defined by GBD. It emerges that, for all 15 pairings among the six causes, these reductions are positively correlated. We introduce metrics to summarize a nation's overall "safety status," and find that losses of longevity because of premature deaths are nearly three decades fewer in the safest countries than in the least safe ones. Turning to possible explanations for the cross-national differences, we find a strong association between a nation's safety status and both its economic wherewithal as indicated by the 2016 GDP per capita (adjusted for purchasing power parity) and its income inequality as reflected by its Gini coefficient.

  PublisherOA PDFDOI

• Aviation Safety: A Whole New World?

  Transportation Science · 2020 · 27 citations

  1st authorCorresponding
  • Aeronautics
  • Engineering
  • Geography

  In 2017, over four billion passengers worldwide embarked on air journeys on scheduled flights. Only eight of them were killed in air accidents. Viewed in isolation, this outcome would suggest that the events that produce aviation deaths are on the verge of extinction throughout the world. However, given the rarity of air disasters, year-to-year passenger death tolls are subject to considerable volatility. Here, we examine worldwide data about fatal aviation events on scheduled passenger flights for the decade 2008–2017 in conjunction with similar data for earlier decades. A major difference between this safety study and others is that we work with probabilistic models customized to aviation safety data, with the aim of distinguishing meaningful patterns from random fluctuations. We show that death risk per boarding over 2008–2017 fell by more than half compared with the previous decade, whereas the world’s nations continued to fall into three highly divergent risk categories. Major new developments in recent years include exceptionally strong safety achievements in China—which is slated to be the world’s largest aviation nation within five years—and the Eastern European members of the European Union—which had a fatality-free record in the last decade that constituted the Union’s strongest performance. A troubling aspect of the findings is that the less developed nations did not gain in aviation safety relative to other countries, despite having considerably more room for improvement.

  PublisherDOI

Frequent coauthors

• Daniel J. Kleitman

  8 shared

• Amedeo R. Odoni

  Massachusetts Institute of Technology

  8 shared

• David P. Farrington

  University of Cambridge

  7 shared

• Alfred Blumstein

  5 shared

• Edward H. Kaplan

  5 shared

• Cynthia Rutherford

  The University of Texas Southwestern Medical Center

  4 shared

• Stan N. Finkelstein

  Massachusetts Institute of Technology

  4 shared

• Michael P. Kaye

  University of Michigan–Ann Arbor

  4 shared

Awards & honors

• President’s Award from INFORMS (1996)
• Expository Writing Award from INFORMS (2001)
• Fellow of INFORMS
• 2002 President’s Citation from the Flight Safety Foundation
• Risk Analysis journal’s 2024 Best Paper Award