The Memorial Tribute to the Great Hani Mahmassani at INFORMS

All those who had the pleasure of knowing Hani Mahmassani, who passed away on July 15, 2025 at the age of 69, will never forget him. He has left us with an incredible void, but lucky are we who were his friends, and/or his students,  and/or colleagues, or collaborators.

Many thanks to Yue Wang of the University of Arizona, who prepared this poster notice for the  Transportation Science and Logistics (TSL) Society memorial tribute event in honor of Hani Mahmassani that took place last week at the INFORMS Conference in Atlanta.

The session began with a Zoom presentation by Roberto Roberti of Italy, this year's recipient of the Stella Dafermos Mid-Career Award, and then it was time for our panel, which was chaired by Karen Smilowitz of Northwestern University, a colleague of Hani's.

At the beginning, we gathered for a photo with Pat Mokhtarian, of Georgia Tech, who joined us. Pat was elected to the National Academy of Engineering, as Hani had been earlier.

Srinivas Peeta of Georgia Tech had prepared the nice collage poster of photos that some of us had also contributed to.

The talks were incredibly touching with Srinivas Peeta speaking about Hani, as his PhD advisor, and colleague, with numerous photos over the years of many luminaries in transportation science. He emphasized what a great researcher Hani was and also an outstanding organizer, integrator, and mentor. 

In my presentation, which is available here:  https://supernet.isenberg.umass.edu/visuals/Hani-Tribute-INFORMS-Nagurney.pdf, I included photos taken over many years of activities, including service ones, I had engaged in with Hani. So many memories came flooding back and I can hear his voice. Hani always inspired us to reach higher and to do more. He stretched us professionally and personally with his many kindnesses and support.

Marco Nie, a colleague of Hani's at Northwestern, had used ChatGPT for his presentation slides, and it was fascinating to see what was picked up by AI in terms of the contributions of Hani's research to transportation science, such as his work on bounded rationality and traffic assignment, and dynamic traffic network equilibrium.

Mike Hyland of UC Irvine, and a former PhD student of Hani's, spoke from the heart about how it was to work with Hani, who only slept a few hours a night. Hani was always willing to listen and to push the frontiers of transportation research and practice. He supervised over 75 PhD theses. 

We then took the group photo below. Thanks to all who were able to join us for this touching memorial session in honor of Hani Mahmassani. 

Thank you, Hani, for your friendship, scholarship, leadership, and for being a visionary.

For the In Memoriam, co-authored by Karen Smilowitz and Marco Nie, and published in the journal Transportation Science, see here: https://pubsonline.informs.org/doi/10.1287/trsc.2025.memorial.v59.n6

The In Memoriam ends as follows: "In 1997, Hani wrote a tribute to Robert Herman in Transportation Science. He closed his tribute with the following words that ring so true to us as we remember Hani: “I will miss him, and so will many others, but will always know that I am a richer person for having known him.”"

Rest in Peace, Professor Hani S. Mahmassani

I received the heartbreaking news that Professor Hani S. Mahmassani, a superstar in transportation science and operations research, passed away on July 15, 2025, from his colleague, Northwestern University Professor Karen Smilowitz. It is truly hard to process that this brilliant scholar and dear friend has passed away. I am sure that many tributes and special memorials will follow but I had to take the time to write my reflection. 

Karen also shared with me the following official message:

NUTC is greatly saddened to share the loss of our dear friend and colleague, Dr. Hani Mahmassani, William A. Patterson Distinguished Chair in Transportation, professor of civil and environmental engineering and director of the Northwestern University Transportation Center at Northwestern University. Dr. Mahmassani passed away this morning, July 15, 2025, at 7:15 AM CDT at Northwestern Memorial Hospital following a sudden cardiac arrest. He was 69 years old. 

Dr. Mahmassani was an outstanding and internationally renowned leader of transportation science and logistic community. During his long and prolific career, spanning more than four decades, Hani made significant contributions to transportation science in various fields: from dynamic network modeling and optimization, to traffic flow theory, intelligent transportation systems, dynamic vehicle routing, travel behavior, decision theory, and logistics systems design. Hani is a member of the National Academies of Engineering, arguably the highest professional honor an engineer can receive. Hani was an exceptional mentor who advised more than 75 doctoral students, many of whom now hold positions on top universities worldwide, showing his high commitment to developing future leaders in transportation. 

Dr. Mahmassani will be remembered by all as a dedicated and enthusiastic member of the transportation community, and our hearts go out to all his friends, family and academic colleagues, particularly his sons Amine and Ziad and his brothers Ghaleb, Maher and Malek.

Information regarding a celebration of life service for Dr. Mahmassani will be shared in the coming weeks.

Hani I have known for decades and I have served on multiple prize committees with him and have engaged in many special activities, which he initiated, as a super dynamic thought leader and innovator. He had served as the Editor in Chief of the flagship journal Transportation Science, a position that Karen Smilowitz now holds.

Last year, I nominated Hani for INFORMS Fellow and, at the INFORMS Fellows Luncheon in Seattle last October, we celebrated his election, along with 11 other inductees, including Grazia Speranza and Celso Ribeiro, with whom I already shared the very sad news. Hani had  been earlier elected to the National Academy of Engineering (NAE) but was thrilled to become an INFORMS Fellow and the announcement below appears on the NU Transportation Center's webpage. 

Below are photos taken at the INFORMS Fellows luncheon in Seattle. Hani was presented with his award plaque by then INFORMS President Julie Swann. In the group photo Hani is with Celso Ribeiro, Grazia Speranza, Janny Leung, who chaired the Fellows selection committee, and me. I saw Celso, Grazia, and Janny recently at the EURO Conference in Leeds.

Hani had also been recognized by the INFORMS Transportation Science & Logistics Society with the Robert Herman Lifetime Achievement Award. Robert Herman had been his mentor when he was at UT Austin, after receiving his PhD from MIT.

Hani was incredibly generous with his time and support of scholars as well as practitioners. For example, he even agreed to serve on the Stella Dafermos Mid-Career Award (inaugural) committee that I chaired and I blogged about that experience https://annanagurney.blogspot.com/2022/10/congratulations-to-niels-agatz-on-his.html. Stella had been my PhD advisor at Brown University and was a friend of Hani's. She passed away at age 49 in 1990. Neils Agatz was the first recipient of this award.

In 2018, I had the great pleasure of speaking at the Smart Cities Analytics Workshop at Western University in Canada with Hani and others that I am sure that some of my readers will recognize:

I blogged about the great experience: https://annanagurney.blogspot.com/2018/10/smart-cities-analytics-terrific.html

In my lecture slides of my Transportation & Logistics class I have photos of Hani and in my Humanitarian Logistics & Healthcare class I speak about his great work on evacuation networks. Hani was an incredible thought leader, who regularly appeared in the media, and who mentored so many scholars and students. 

I remember fondly the events that he organized at Northwestern University, including the event on the publication of the book  "Forecasting Urban Travel," co-authored by David Boyce and Huw Williams, which I was honored to take part in; see https://annanagurney.blogspot.com/2015/10/fabulous-launch-of-forecasting-urban.html and also the outstanding event - a Network Design Symposium in honor of Martin Beckmann (who was on my PhD committee): https://annanagurney.blogspot.com/2010/01/what-transportation-symposium.html

And, in 2005, at the INFORMS meeting in San Francisco, David Boyce and I organized 2 sessions in honor of the 50th anniversary of the publication of  Studies in the Economics of Transportation, and the photo below was taken after the sessions. Beckmann and McGuire were present, along with their spouses. Winsten had passed away the year before. Hani is on the far left in the photo.

Hani was also the Editor in Chief of Transportation Science when Dietrich Braess, Tina Wakolbinger and I published the translation of the famous Braess paradox (1968) paper from German to English along with a preface by David Boyce and me on how Braess came up with the idea. See: https://pubsonline.informs.org/doi/10.1287/trsc.1050.0127 and https://pubsonline.informs.org/doi/10.1287/trsc.1050.0126

And I am so pleased that Hani, David Boyce and I published the following article together: http://www.civil.northwestern.edu/docs/Boyce/retrospective_on_beckman.pdf

Below is a photo of Hani and the rest of the award committee, including me, when Michael Florian received the Robert Herman Lifetime Achievement Award, back in 1998. With us is Marius Solomon, who has since passed away, Mark Daskin, Gilbert Laporte, and Teo Crainic.

Thank you, Hani, for your outstanding contributions, your selflessness, generosity, great wisdom and knowledge, and kindness and for all the memories. Your legacy will live on through all those who were blessed to have had you in their lives and through your outstanding scientific work.

And Sobhi Mahmassani, a nephew of Hani's, was a student in my Transportation and Logistics class at the Isenberg School of Management and an OM major!

Deepest condolences to Hani's family, friends, students (present and past) and to all the colleagues around the world!

It's Official - Announcement of Stella Dafermos Achievement Award in Transportation Science, Thanks to TSL Society of INFORMS!

This morning the business meeting of the Transportation Science and Logistics (TSL) Society of INFORMS took place in a virtual format. There were over 100 participants, with even Norway, Germany, and Israel represented!

I'd like to thank the President of TSL, Professor Mike Hewitt, for running a very professional, and swiftly moving, meeting at which there were many wonderful award announcements and professional updates.

It is now official - I have known about this for months but had to be quiet until the announcement today. 

I am delighted that the TSL Society is recognizing my PhD dissertation advisor, Professor Stella Dafermos, who, sadly, passed away in April 1990 at age 49, with an award in her honor - Stella Dafermos Achievement Award in Transportation Science. I was her first PhD student

I will be chairing the first award committee and am deeply moved and honored.

I'd like to sincerely thank the President and the Board of the TSL Society for recognizing this amazing female trailblazer and role model in this significant way.

I was asked to prepare a short speech highlighting her contributions. 

The slide deck of my presentation can be downloaded here.

The video recording of my presentation can be viewed here.

Stella made herstory/history, in many respects.  She was the second female recipient of a PhD in Operations Research in the US and was the first female Full Professor in Engineering and in Applied Mathematics at Brown University, which she achieved in 1982.

Her 1980 paper, "Traffic Equilibrium and Variational Inequalities," published in the INFORMS journal, Transportation Science, was among the list of 12 most impactful papers in the journal over its 50 year history, as of 2016. All these classic papers can be downloaded for free on the above link provided.

Stella Dafermos had the highest standards when it came to scientific research.  She was guest editing a special issue on Network Equilibrium of Transportation Science, when she passed away, so Professor Amedeo Odoni of MIT and I completed the editorial process and we also published an In Memoriam to Stella in the special issue.

As I said in my speech this morning, "One wonders how much the world has missed because of her untimely passing."

I leave you with a photo of  Stella with Professor George Nemhauser that I took in Tokyo at the Mathematical Programming Symposium, August 28 - September 2, 1988. Stella loved conferencing and I enjoyed travel with her very much as well as publishing with her in many journals, including Operations Research and Mathematical Programming as well as Transportation Science, among others.

When I informed Stella’s husband, Dr. Constantine Dafermos, the Alumni-Alumnae University Professor Applied Mathematics at Brown University,about the Stella Dafermos Achievement Award, he responded, “I am delighted, moved and also – on behalf of Stella – honored.” “I feel that establishing the prize is a major service to your field, as it will serve as a recognition of the contributions in the early days and as a reminder that women were among these contributors.”

Let's continue to do our very best to uphold the highest standards that she set.

My 200th Article - Remembering a Great One

This week I finished a paper with a colleague of mine, Professor Patrizia Daniele of Italy, which I had been invited to submit to a special issue of a journal. The paper is on international human migration networks, a topic that is very timely, given the various refugee crises around the globe. The topic of human migration I have been publishing on for over 25 years and it is even tackled, using network models, in my first book, Network Economics: A Variational Inequality Approach, published in 1993, with the second edition appearing in 1999.  In the book, the first citation in the chapter on migration is to  Beckmann, M., “On the equilibrium distribution of population in space,” Bulletin of Mathematical Biophysics 19 (1957) 81–89. 

Professor Martin Beckmann was a member of my PhD committee at Brown University, which was chaired by my dissertation advisor, Professor Stella Dafermos. He was renowned in economics, regional science, and transportation science and was the recipient of the Robert Herman Lifetime Achievement Award of the Transportation Science Section of  ORSA/TIMS, now INFORMS. He received this award in 1994, and you can read the wonderful tribute to him on the occasion of this award by David Boyce, published in Transportation Science. 

Professors Boyce, Hani Mahmassani, and I wrote a retrospective on Beckmann, McGuire, and Winsten's landmark book, Studies in the Economics of Transportation, that was published by Yale University Press.

And, in 2005, at the INFORMS meeting in San Francisco, David Boyce and I organized 2 sessions in honor of the 50th anniversary of the publication of  Studies in the Economics of Transportation, and the photos below were taken after the sessions. Beckmann and McGuire were present, along with their spouses. Winsten had passed away the year before.

Professor Beckmann passed away at age 92 in the spring of  2017  and his family reached out to me to invite me to attend an informal memorial service in the Beckmann home in Providence, Rhode Island. My husband and I were able to attend and to express our deepest condolences to his family members and also to recall numerous wonderful experiences that we had had with Professor Beckmann in many countries, from Sweden to Australia! I wrote a reminiscence is his honor after returning from the service,where I also posted quite a few photos of various events over the years, several that were in his honor. I had earlier written a tribute to him on the occasion of his 90th birthday and his son acknowledged it.

Since David Boyce and I had written an "In Memoriam" on the passing of Beckmann's co-authors: McGuire and Winsten, published in Transportation Science, it was only fitting to have Martin Beckmann be honored in the same way. Hence, when David Boyce approached me this summer to co-author an "In Memoriam" in honor of Martin, I willingly accepted the offer.  This gave us the opportunity to reflect some more on his extraordinary contributions, his effervescent personality, his incredible intellect, lust for travel, and his love of  great food and adventure and music and friendships.

Our article, "In Memoriam: Martin Beckmann (1924-2017),"  has been accepted for publication by the Editor of Transportation Science, Professor Martin Savelsbergh. And, coincidentally, and, this is bittersweet - this is my 200th journal article. Beckmann's work has influenced so much of my work on networks (and that of so many others) that I wish that I could, once again, speak with him. His work will continue to inspire me, my students, co-authors, and all those who are captivated by the interaction of users of many complex networks that underpin our societies and economies. Thank you ever so much, Professor Martin Beckmann!

Isenberg School Supernetwork Center Associates Presenting at ISSR Research Beyond the Academy Conference at UMass

This is a fabulous week with tonight the Isenberg School Scholarship Celebration taking place at the Marriott Center at UMass Amherst; tomorrow the UMass Amherst Honors dinner at the Campus Center as well as the Isenberg School Senior Barbecue plus All School meeting immediately prior, and Friday is a special conference organized by the Institute for Social Science Research (ISSR) at UMass. And, yes, we are still conducting classes!

Friday's conference is on Social Science Research Beyond the Academy with PhD alum panelists and a graduate student research exposition.

My former doctoral student in Management Science at the Isenberg School, Dr. Padma Ramaujam, who is with SAS in Cary, North Carolina, and with whom I co-authored the Emvironment Networks book, will be a panelist.  Padma's dissertation received an INFORMS Transportation Science Section (now the Transportation Science & Logistics Society) best dissertation award, a highly prestigious honor.

Also, my doctoral student, Shivani Shukla, will be presenting a poster at this conference on our latest research on cybersecurity investments.

Dr. Laurel Smith-Doerr, the Director of ISSR, provided me with the nice flyer, reposted below, which mentions Padma and Shivani, both of whom are Supernetwork Center Associates.

It should be a great event and week filled with so many celebratory activities recognizing the achievements of students and faculty!

Being an Operations Research Paradigm Changer

I do believe that female voices need to be heard and not silenced and that is one of the reasons that I started this blog over 5 years ago.

This week I had to recall Stella Dafermos, since her birthday was April 14, and, since she was born in 1940, had she lived, she would have been 75 years old this year!

Stella Dafermos was my dissertation advisor at Brown University and she was the second female PhD in Operations Research in the world. She passed away on April 4, 1990 - 25 years ago, which is shocking. I spoke with Dr. Elise Miller-Hooks this week, who is now at NSF as a Program Director, and on leave from the University of Maryland. Elise was instrumental in having a Best Paper Award named in honor of Stella at the Transportation Research Board (TRB) Annual Meeting in DC. The first recipient of this award was Dr. Tao Lin of Virginia Tech for a single-authored paper but Elise told me that the web developer left and, hence, sadly, there has not been a big official announcement of the award

Stella was an Operations Research Paradigm Changer and I would say even a Research Paradigm Changer with her tremendous contributions to variational inequality theory, models, and algorithms, which allowed for the formulation, analysis, and rigorous solution of more general traffic network equilibrium problems that had, to that point been possible. The applications of variational inequalities now transcend operations research and transportation science and are fundamental to supply chains, game theory, regional science,  economics and finance, as well as ecology.

I am delighted that the book by Boyce and Williams, the cover of which is featured below, will be available soon.

Chapter 7 in the book, which I had the pleasure to review and comment on because Professor David Boyce forwarded me the draft to read over,  emphasizes the contributions of Stella to Transportation Network Equilibrium and I was delighted to see several of our joint papers cited.

Stella, to this date, remains the only female whose memory and contributions are honored by the premier journal Operations Research with an obituary,  that I wrote.

It's research that is a paradigm changer that is truly brilliant! Her legacy continues to impact both research and practice in complex network and decision-making. She set the highest standards, which I try to impart to my students now.

Looking Forward to New Book, Forecasting Urban Travel, by Boyce and Williams

I heard from my great colleague and friend, Professor David E. Boyce, who forwarded me his holiday letter that the book that he has been immersed in writing, with Professor Huw Williams, Forecasting Urban Travel: Past Present and Future, is in the final stages of production with the publisher, Edward Elgar.

On the book cover, featured above, are images of two of David's favorite cities, Chicago and Singapore. The book should be available for purchase in April 2015 from www.e-elgar.com/. Initially, it will be offered in hardcover and e-book formats. Within a year, according to David, a lower-priced paperback edition will then be issued. Finally, a Chinese translation is underway, which is quite exciting!

According to a news item published in the TSL (Transportation Science and Logistics Society) of INFORMS Fall 2014 newsletter, which we received just last week: The book presents, in a non-mathematical way the evolution of methods, models and theories underpinning travel forecasts and policy analysis, from the urban transportation studies of the 1950s to current applications throughout the urbanized world. From original documents, correspondence and interviews, especially from the United States and the United Kingdom, the authors seek to capture the spirit and problems faced in different eras, as changing information requirements, computing technology and planning objectives conditioned the nature of forecasts.

I have had the pleasure of seeing Chapter 7 of the book, which is on Transportation Network Equilibrium, which David asked me to provide feedback on, which was a pleasure to do, since it was like a trip down memory lane, during which I reminisced about the contributions of my doctoral dissertation advisor at Brown University, Professor Stella Dafermos, and her amazing contributions. It was also a pleasure to read and reflect on the work that we did jointly prior to her death.

I am sure that this book will be a classic in transportation science as well as the history of travel forecasting and am very much looking forward to its publication in the spring of 2015. Chapter 7, alone, is worth the price of the book, since there is a very human aspect to the rendition of discoveries therein and the individuals involved.

The contents of the book below are from the publisher's website:

Contents
Contents: Preface 1. Introduction 2. Emergence of the Traditional Approach 3. Early Developments in the UK 4. Travel Forecasting based on Discrete Choice Models, I 5. Travel Forecasting based on Discrete Choice Models, II 6. Activity-Based Travel Analysis and Forecasting 7. Transportation Network Equilibrium 8. Tradition and Innovation in US Practice 9. Tradition and Innovation in UK Practice 10. Computing Environment and Travel Forecasting Software 11. Achievements, Current Challenges and Future Prospects 12. Conclusion Index

Transportation Research Board of the National Academy of Sciences Honors Memory of Operations Research Female Superstar

I received the news when I was at the Cities, Energy, and Complex Systems Workshop in Erice, Sicily, which took place May 11-14, 2014.
http://tinyurl.com/mrgqxy6


Yesterday, I traveled back from Erice to Palermo to Munich and, finally, to Gothenburg, Sweden where I am a Visiting Professor.

Professor David E. Boyce sent me a message that the Transportation Network Modeling Committee of the Transportation Research Board of the National Academy of Sciences has introduced a best paper award in honor of my doctoral dissertation advisor at Brown University, Professor Stella Dafermos. Stella was the second female to receive a PhD in Operations Research in the world and died at the age of 49.

More information on this award is available here:
http://tinyurl.com/me97o7f

Professor Boyce told me that much of the credit to making this happen belings to Professor Elise Miller-Hooks and I thank all those who made this important recognition of Stella's great contributions happen.

Stella passed away almost 25 years ago and made lasting contributions to the modeling of network equilibria in transportation science, operations research, and economics. When she passed away I was asked to write an obituary in her honor which was published in our journal Operations Research.


Interestingly, while in Erice, at one of the delicious dinners, I sat next to Dr. Aristides Patrinos, who is Greek, and who is heading NYU's Center on for Urban Science + Progress. We ended up talking aout the Dafermos family since he has served on scientific funding panels with Professor Constantine Dafermos, Stella's husband.

Dr. Patrinos is the only person that I have ever met whose face graces a postage stamp and he surprised me with a few stamps with his image.

Terrific Talk on Transportation Science + Economics

Today we had the pleasure of hosting Dr. Eric Gonzales of the Civil and Environmental Engineering Department at UMass Amherst in our INFORMS Speakers Series. Dr. Gonzales, who received his PhD from UC Berkeley, and then spent 2 and a half years at Rutgers, recently joined the UMass faculty.

His talk, "Coordinating Traffic and Transit Systems: Linking Transportation Science and Economics," was fabulous. He discussed system optimization and user equilibrium with tipping points of switching to transit. I especially liked his use of numerous images and graphs to display trade-offs as well as his discussions of different cities around the world. He emphasized how to capture congestion in cities in an aggregated way. Several of the students in the audience had taken my Logistics and Transportation class as well as my graduate class on Networks, Game Theory, and Variational Inequalities, so they could very much appreciate his perspective.

Below are several photos that I took today at Dr. Gonzales' presentation at the Isenberg School, which attracted an audience also from the College of Engineering.

We are very lucky that Dr. Gonzales has joined the faculty at UMass Amherst! His dissertation advisor at UC Berkeley was Professor Carlos Daganzo, who was recently elected to the National Academy of Engineering.

Save the Dates - Two Upcoming Techie Talks at the Isenberg School Thanks to the UMass Amherst INFORMS Student Chapter

Spring break is over and we have only about 6 weeks of the spring semester left.

The UMass Amherst INFORMS Student Chapter and I, as the Chapter's Faculty Advisor, are quite excited about our upcoming speakers.

This Friday, March 28, we will be hosting Dr. Eric Gonzales of the Civil and Environmental Engineering Department at UMass Amherst. He will be speaking on Coordinating Traffic and Transit Systems: Linking Transportation Science and Economics. Dr. Gonzales received his PhD from UC Berkeley and his dissertation advisor was Professor Carlos Daganzo, who is the most recent recipient of the Robert Herman Lifetime Achievement Award in Transportation Science announced at the INFORMS Minneapolis meeting last Fall. Dr. Daganzo was also elected to the National Academy of Engineering in 2014.  Professor Gonzales was previously at Rutgers University and we are very happy that he is now, as of this semester, at UMass Amherst.

Also, on Friday, April 18, we will be hosting my colleague, Professor Ryan Wright of the Operations & Information Management Department. Professor Wright will be speaking on Towards a Behavioral Model of Online Deception Detection. This topic is also fascinating. Dr. Wright is a fellow Canadian and he and I spoke at the UMass Amherst TEDx event last November and were nominated by students, which was such a nice and pleasant surprise. He instructs the required information management course at the Isenberg School to an audience of hundreds.

I hope that you can join us for these talks. We have also invited another speaker so stay tuned!

For more information about the UMass Amherst INFORMS Student Chapter, please visit its website.

Congrats to 2014 Newly Elected National Academy of Engineering Members - a Great List with Operations Research represented

After teaching my Humanitarian Logistics and healthcare class this morning I heard the great news.

Today the National Academy of Engineering announced its 2014 list of newly elected members and what a terrific list it is! 


Time to celebrate.

On the list are several individuals that are well-known in Operations Research and Analytics circles and I am so happy for them -- they are great individuals. Their citations are below


Dr. Carlos Daganzo, Chancellor Professor of the Graduate School, and retired Robert Horonjeff Chair in Civil and Environmental Engineering, University of California, Berkeley.  For engineering contributions to traffic, transportation, and logistics systems and operations.


Dr. Brenda Dietrich,  IBM Fellow and vice president, and chief technology officer for Business Analytics Software, IBM, Somers, N.Y.  For contributions to engineering algorithms, frameworks, and tools to solve complex business problems.


Dr. Wallace Hopp, senior associate dean for faculty and research, Herrick Professor of Business, professor of technology and operations, and professor of industrial and operations engineering, University of Michigan, Ann Arbor.  For creating and applying fundamental engineering principles governing the underlying behavior of manufacturing systems and supply chains,


Dr. Alex "Sandy" Pentland, Toshiba Professor of Media, Arts, and Sciences; and director, Human Dynamics Laboratory and Media Lab Entrepreneurship Program, Massachusetts Institute of Technology, Cambridge.  For contributions to computer vision and technologies for measuring human social behavior.
 
Dr. Daganzo is the recipient of the Robert Herman Lifetime Achievement Award in Transportation Science, which he received at the INFORMS Minneapolis Meeting in October 2013.

Both Dr. Dietrich and Dr. Pentland have spoken in our UMass Amherst INFORMS Speaker Series at the Isenberg School of Management plus they were plenary speakers at the First Northeast Regional INFORMS Conference held at UMass Amherst in May 2011, which I helped to organize with Dr. Hari Balasubramanian of UMass Amherst and Dr. Les Servi of MITRE. A blogpost and photos are available here.

I have also interacted with Dr. Pentland on other occasions, including the SBP set of conferences in which I served as a tutorial chair for several years and he gave a fabulous tutorial!

Special congrats also to Dr. Hopp for his great work and much-deserved recognition.

*******Plus, an update from the INFORMS homepage, congrats  also to INFORMS member:  Dr. Stephen Boyd,  Samsung Professor in the School of Engineering; and professor, Information Systems Laboratory, department of electrical engineering, Stanford University, Stanford, Calif.  For contributions to engineering design and analysis via convex optimization.********

The Braess Paradox is Back and in New Scientist

This week I received a message from none other than Professor Dietrich Braess after whom the (in)famous paradox is named -- wherein adding a route to a transportation network can make the commute for all travelers longer! (Or, removing a road can get you to work faster!)

I am a big fan of Professor Braess' work and his paradox paper, which was written in German and published in 1968. I not only wrote about it in my doctoral dissertation, but have enjoyed building upon it  since.

Plus, I had the distinct honor, along with my doctoral students and the UMass Amherst INFORMS Student Chapter, of hosting Professor Braess' first visit to the U.S., back in April 2006, to speak specifically on his paradox.  In addition, we were celebrating the translation of his paper from German to English, which Braess and I did, along with my doctoral student from Austria, Tina Wakolbinger, who is now a Full Professor in Vienna. The translation was published in the INFORMS journal, Transportation Science, along with a preface, written by Professor David E. Boyce and me. 


The photos of Braess below were taken at the Isenberg School and at the University Club.

 

The photo immediately above was taken in my Supernetworks Lab at the Isenberg School. Professor Braess, Tina, and I are holding our translation in Transportation Science. Additional photos as well as a link to Professor Braess' presentation can be found on this page.

Professor Braess wrote me that New Scientist was writing a story on the paradox, which has just appeared and is by Justin Mullins. It is entitled: "42nd St paradox: Cull the best to make things better" and a preview is here.  I managed to access a copy, although the official publication date is not until January 18, 2014.  The article also notes Skinner's work vis a vis basketball and the Braess paradox, which I spoke about in the PBS America Revealed segment Gridlock (a great experience to be interviewed by the winner of Survivor in 2006, Yul Kwon!) and have written about on this blog.  New Scientist also mentioned Professor Adilson Motter of Northwestern University, who led the recent Network Frontiers Workshop in December that I spoke at on Envisioning a Future Internet.Architecture.

Motter is quoted in  the New Scientist article on his ecology work (networks are everywhere!):  In certain circumstances,  the early removal of a species that would otherwise eventually go extinct anyway can prevent all secondary extinctions and improve the entire system's viability. That's an analogue of Braess's paradox, says Motter. 

The New Scientist article also talks about Professor Dirk Witthaut's work on the electric grid and concludes:  It is very early days in our understanding of biological networks. But if Motter, Witthaut and others have their way, counter-intuitive network effects may have a much more significant role to play in future. It may even be the key that helps the Knicks to another NBA play-off, and perhaps even reunites them with the championship trophy that has long eluded them.

And speaking of the Braess paradox, I have posted below a link to the video captured at the great UMASS Amherst TEDx event at which I spoke on The Traffic Circle of Life and, of course, the Braess paradox!


Anna Nagurney from TEDxUMassAmherst on Vimeo.

The lecture slides can be downloaded here.

What if Your PhD Advisor for Your Second PhD Was Also Your PhD Student

Life in academia is never dull and the surprises continue.

A few weeks ago, I was asked to be on the doctoral dissertation committee of a student at the Royal Institute of Technology (KTH) in Stockholm, Sweden. For logistical reasons -- the defense was to take place on June 1 in Stockholm and since my apartment in Gothenburg was not yet confirmed I declined (although I very much wanted to be on this committee).

In the meantime, my wonderful hosts at the School of Business, Economics and Law at the University of Gothenburg found me a wonderful apartment in which I will be staying for the month of June.

The "student" who was defending his doctoral dissertation, and, I might add, successfully passed it, was PO Lindberg, who already has a PhD, which he received in 1975.  PO even achieved  the rank of Full Professor. He is well-known in operations research and mathematical programming circles and has been a friend since I received my PhD.

Those of you who are reading this post closely, must now be impressed that someone, who already has a PhD, got a second PhD and 37 years after his first! His second PhD is in Transportation Science.

However, that is not the full story.

PO´s former doctoral student, Lars-Goran Mattsson, was his dissertation advisor for his second PhD!

As PO stated in the acknowledgments in his dissertation, what will this do to his mathematics genealogy tree!

In academic genealogy and the academic family tree,  the son (Lars-Goran Mattsson) of his father (PO Lindberg) is now his father´s father.

Most Influential Articles on the Economics of Traffic Congestion and Our Translation of the Braess Paradox Article is Included

I had not even realized until this past week that the edited volume, The Economics of Traffic Congestion, containing

the most influential articles written over the past eight decades that contribute to an understanding of the economics of traffic congestion

had been published by Edward Elgar Publishing in its series: the International Library of Critical Writings in Economics.

When I saw the list of articles that had been reprinted, I was struck by the names of the authors, many of whom I cite very regularly in my papers and books since their works are, indeed, classics in transportation.

And then I saw my name on the paper with Braess and Wakolbinger in the first volume; see the contents of Part I of the first volume below, taken from the Edward Elgar page on this book.

Contents:

Volume I

Acknowledgements

Introduction Erik T. Verhoef

PART I CONGESTION AND ROAD PRICING: CLASSIC CONTRIBUTIONS
1. A.C. Pigou (1920), 'Divergences between Marginal Trade Net Product and Marginal Individual Net Product'
2. F. H. Knight (1924), 'Some Fallacies in the Interpretation of Social Cost'
3. John Glen Wardrop (1952), 'Some Theoretical Aspects of Road Traffic Research'
4. Martin Beckmann, C.B. McGuire and Christopher B. Winsten (1956), 'Equilibrium' and 'Efficiency'
5. M.J. Lighthill and G.B. Whitham (1955), 'On Kinematic Waves. II: A Theory of Traffic Flow on Long Crowded Roads'
6. Paul I. Richards (1956), 'Shock Waves on the Highway'
7. A.A. Walters (1961), 'The Theory and Measurement of Private and Social Cost of Highway Congestion'
8. William S. Vickrey (1963), 'Pricing in Urban and Suburban Transport'
9. Dietrich Braess, Anna Nagurney and Tina Wakolbinger (2005), 'On a Paradox of Traffic Planning' [Translated from the German: D. Braess (1968), 'Über ein Paradoxon aus der Verkehrsplanung']

To be in a volume with Pigou, Knight, Wardrop, Beckmann, McGuire, and Winsten, Lighthill, and even the Nobel Laureate Vickrey, is humbling, to say the least.

The full contents of volumes I and II are available here and what a wonderful list of "classics." Plus, I can say that in this group there are even quite a few still with us that I consider my friends.

We had been approached by the editor of this two volume edition, Eric Verhoef, a while back, and Dietrich Braess, Tina Wakolbinger, and I had given permission to have our article, published originally in 2005, in the journal, Transportation Science (which is an INFORMS journal), reprinted and had gotten the necessary permissions. The article is unusual since it is a translation of the famous Braess (1968) paradox paper from German to English, that was accompanied by a preface written by David E. Boyce and me.

According to the publisher: The first volume explores the classic contributions on congestion and road pricing and includes papers in dynamic models and second-best congestion pricing. The second volume analyses ownership arrangements such as private roads, investment and financing, urban land use, social acceptability and distributional aspects of road pricing.

Professor Dietrich Braess visited the Isenberg School of Management at UMass Amherst shortly after our translation was published. Tina Wakolbinger, who, at the time,was one of my doctoral students at UMass Amherst, and I, along with others had a wonderful time hosting him and he spoke in our UMass Amherst INFORMS Speakers series. Some photos and other information can be found here. Tina is now a Full Professor at the Vienna University of Economics and Business.

This volume also brings forth some of the amazing synergies between economics and operations research, a theme that has always been very dear to me and my research. But then again, Martin Beckmann was on my doctoral dissertation committee at Brown University, with Stella Dafermos as my dissertation chair. George Majda, who, like Stella, died much too young, was my other committee member. Beckmann is still with us and continues to amaze with his mind and love of life.

Braess Paradox Revisited, the American Mathematical Society, and INFORMS

I was delighted to read this month's Feature Column of the American Mathematical Society (AMS) written by Professor John Malkevitch of York College of the City University of New York. The teaser to the article: How does a free market approach work when applied to road networks? The article discusses both the Prisoner's Dilemma and the Braess Paradoxis that illustrate that there are situations where, if individuals are left to make their own decisions, the result might be that as a group or as individuals they are worse off.

The article cites the translation of the famous Braess (1968) paradox article from German to English that I did with Braess and my former doctoral student, Tina Wakolbinger (see the bottom photo above), and that was published in 2005 in the journal, Transportation Science.

We hosted Professor Dietrich Braess in April 2006 at the Isenberg School and he spoke on how he came to devise the paradox, now named after him. He delighted us with his presentation (amazingly we were the first in North America to ever invite him to speak on this topic) and he stayed with us for several days.

When I look at the photo above with many of the audience members following his talk it pleases me how many are now professors around the world -- from Dr. Dmytro Matsypura who is now at the University of Sydney (tenured) to Dr. Tina Wakolbinger who will soon be assuming her professorship at the Vienna University of Economics and Business to Dr. Christian Wernz who is a professor at Virginia Tech, to Dr. Shenghan Xu, who is a professor at the University of Idaho, to Dr. Zugang Liu, who is a professor at Penn State Hazleton, and Dr. Patrick Qiang, who is a professor at Penn State Malvern, plus Dr. Trisha Woolley, who is a professor at Texas Wesleyan University and Dr. Deanna Kennedy who is at the University of Washington Bothell.

That year I was a Science Fellow at the Radcliffe Institute for Advanced Study at Harvard University and somehow still managed to help our students of the UMass Amherst INFORMS Student Chapter organize and host an incredible lineup of speakers in the Spring of 2006 and the Fall of 2005.

The visit of Professor Dietrich Braess was one of the highlights and you can find more information about his visit here, with links to the translation and even the preface that I wrote with Professor David E. Boyce.

I thank Professor Malkevitch for writing the Feature Column that brought back so many delightful memories!

As for my most recent research on the Braess paradox (something I was even fascinated by in my doctoral dissertation at Brown University), see my article in Europhysics Letters on the wisdom of crowds.