Sunday, January 16, 2022

Congratulations to the Supernetwork Team at the Isenberg School of Management for a Great Year!

As we begin the New 2022 Year, it is time to take stock and to reflect on the year that has passed.

2021 was a remarkable year in many respects, not the least of which was that it marked the second year of the COVID-19 pandemic.  As the Center Director, I feel it to be important to share with you reflections on this extraordinary year, and to highlight some of the accomplishments of ours at the Virtual Center for Supernetworks.

In 2021, the book, "Dynamics of Disasters - Impact, Risk, Resilience, and Solutions," that I co-edited with Professors  Ilias S. Kotsireas and  Panos M. Pardalos, and Dr.  Arsenios Tsokas was published by Springer. In it, you will find many fascinating contributions, all peer-reviewed, including co-authored work by Center Associates Professor Patrizia Daniele of the University of Catania in Italy and Professor Tina Wakolbinger on the Vienna University of Economics and Business in Austria. My paper - the very first on incorporating labor into supply chain networks, which was done in the context of perishable food supply chains, also appears therein. And, in July 2021, we, again, co-organized another Dynamics of Disasters conference, which this year, because of the pandemic, although based in Athens, Greece,  nevertheless, virtual. The conference included four plenary speakers and we were delighted to hear from all of them, including Center Associate Dr. Stavros Siokos of Astarte Capital, which he co-founded in London. Center Associates were very active at this conference and included presentations of work by Center Associates Professor Patrizia Daniele,  Professor Tina Wakolbinger, Professor Deniz Besik of the University of Richmond, Professor Pritha Dutta of Pace University, Professor Ladimer S. Nagurney of the University of Hartford,  and Isenberg Doctoral Student Center Associate Mojtaba Salarpour. Mojtaba successfully defended his doctoral dissertation in March 2021.
On June 7, 2021, I was deeply honored with the receipt of the 2020 Harold Larnder Prize from the Canadian Operational Research Society.  I delivered my talk, "Novel Supply Chain Network Models Inspired by the COVID-19 Pandemic: From Optimization to Game Theory," virtually and, remarkably, the prize certificate was delivered through express courier services around the same time!  The video of my prize lecture can be viewed here. I am only the second female in its 35 year history to receive this prize - the first one was Dr. Ailsa Land, who, sadly, died in 2021. I was honored to be a panelist to recognize her receipt of the Beale Medal, which I blogged about.
In the pandemic, our expertise on supply chains and various network systems continued to be sought after. Since part of the Center's focus is public outreach, in addition to our mission of research and education, we responded to numerous media interview requests from the print media, radio shows, as well as TV news programs, and podcasts.  Print media coverage can be viewed here. For various TV and radio interviews plus podcasts, see here,
Center Associates presented at the EURO Conference as well as the INFORMS Conference, which was in hybrid format, with Professor Deniz Besik presenting at this Anaheim conference in person as well as Center Associate Professor Sara Saberi of WPI and Mojtaba Salarpour. I had the honor and pleasure of giving a tutorial at the INFORMS conference, which was recorded - "Game Theory and the COVID-19 Pandemic," which is also an INFORMS publication in its tutorial series. I thank Professors John Carlsson and Doug Shier for their great assistance and support.
In addition, to other conference presentations, we took part in an interesting conclave in India and a workshop in  Nepal, demonstrating the reach of the research that we do.  Of particular focus this year, was researching various supply chain disruptions in the pandemic, continuing work on food supply chains, modeling various trade measures in the pandemic, expanding on disasters and game theory, and  including labor into various supply chain networks in a series of papers,  as well as constructing models of human migration and associated policies, and even building a model of convalescent plasma donations! I was deeply honored that my paper, "Supply Chain Game Theory Network Modeling Under Labor Constraints: Applications to the Covid-19 Pandemic," that was published in the European Journal of Operational Research, receive a 2021 Editor's Choice Award.

I am also very grateful to Isenberg Dean Anne P. Massey and to the UMass President Marty Meehan for appointing me  the Eugene M. Isenberg Chair in Integrative Studies in April 2021.  I am very appreciative of having held the John F. Smith Memorial Professorship of Operations Management from 1998 until that point and especially thank my wonderful benefactor - Jack Smith, the former CEO and Chairman of the Board of General Motors and a UMass Amherst alumnus. 

Center Associates achieved additional accolades. Professor Deniz Besik submitted a letter with testimony to Congress on food insecurity in the pandemic. Professor Pritha Dutta was interviewed by FOX on supply chain disruptions in the pandemic, and Professor Sara Saberi received a major NSF grant to help Massachusetts manufacturing prepare for future crises.

In addition, it was a great year - despite the pandemic - for the UMass Amherst INFORMS Student Chapter, which I have served as the Faulty Advisor of since 2004. We hosted several panels as well as Dr. Mauricio Resende of Amazon and Dr. Robin Lougee, formerly of IBM in our Speaker Series! The chapter was recognized by INFORMS with the Cum Laude Award at the Annual Meeting in Anaheim. Mojtaba Salarpour, continued to serve as the Chapter President until September 2021, completing two years of exceptional service.

Plus, it was uplifting to be the invited Faculty Speaker at the UMass Amherst Chancellor's Donor Breakfast in November. The title of my presentation was: "From Supernetworks to Supply Chain in the Pandemic."

We continued to write OpEds, several of which were published in The Conversation, including my article on the shipping container, that appeared on September 21, 2021, and, to-date, has over 315,000 reads!

And, to show the research that we are engaged in, below I highlight some of our recent publications:

Supply Chain Networks, Wages, and Labor Productivity: Insights from Lagrange Analysis and Computations
Anna Nagurney, to appear in Journal of Global Optimization.

A Multiperiod Supply Chain Network Optimization Model with Investments in Labor Productivity Enhancements in an Era of COVID-19 and Climate Change
Anna Nagurney, accepted for publication in Operations Research Forum.

Optimization of Investments in Labor Productivity in Supply Chain Networks
Anna Nagurney, accepted for publication in International Transactions in Operational Research.

Wage-Dependent Labor and Supply Chain Networks in the COVID-19 Pandemic and Beyond
Anna Nagurney, in press in Analysis, Geometry, Nonlinear Optimization and Applications, P.M. Pardalos and T. M. Rassias, Editors World Scientific Publishing, Singapore, October 2021.

Game Theory and the COVID-19 Pandemic
Anna Nagurney, in INFORMS TutORials in Operations Research, October 2021. Also presented at the INFORMS 2021 Annual Meeting.

Modeling of Covid-19 Trade Measures on Essential Products: A Multiproduct, Multicountry Spatial Price Equilibrium Framework
Anna Nagurney, Mojtaba Salarpour, and June Dong, International Transactions in Operational Research 29(1), 2022, pp 226-258.

A Multiclass, Multiproduct Covid-19 Convalescent Plasma Donor Equilibrium Model
Anna Nagurney and Pritha Dutta, Operations Research Forum 2, 31 (2021) Open Access on SpringerLink

Spatial Price Equilibrium, Perishable Products, and Trade Policies in the Covid-19 Pandemic
Anna Nagurney, Montes Taurus Journal of Pure and Applied Mathematics 4(3), 2022, 9-24.

A Multicountry, Multicommodity Stochastic Game Theory Network Model of Competition for Medical Supplies Inspired by the Covid-19 Pandemic
Mojtaba Salarpour and Anna Nagurney, International Journal of Production Economics 235: (2021), 108074.

Optimization of Supply Chain Networks with Inclusion of Labor: Applications to COVID-19 Pandemic Disruptions
Anna Nagurney, International Journal of Production Economics 235: (2021) 108080.

Perishable Food Supply Chain Networks with Labor in the Covid-19 Pandemic
Anna Nagurney, Dynamics of Disasters - Impact, Risk, Resilience, and Solutions, I.S. Kotsireas, A. Nagurney, P.M. Pardalos, and A. Tsokas, Editors, Springer Nature Switzerland AG, 2021, pp 173-193.

Capacitated Human Migration Networks and Subsidization
Anna Nagurney, Patrizia Daniele, and Giorgia Cappello, Dynamics of Disasters - Impact, Risk, Resilience, and Solutions, I.S. Kotsireas, A. Nagurney, P.M. Pardalos, and A. Tsokas, Editors, Springer Nature Switzerland AG, 2021, pp 195-217.

Preface to Dynamics of Disasters Impact, Risk, Resilience, and Solutions, Ilias S. Kotsireas, Anna Nagurney, Panos M. Pardalos and Arsenios Tsokas, Editors, Springer Nature Switzerland AG, 2021, pp v-xii.

International Human Migration Networks Under Regulations
Anna Nagurney and Patrizia Daniele, European Journal of Operational Research 291(3): (2021), pp 894-905.

Networks in Economics and Finance in Networks and Beyond: A Half Century Retrospective
Anna Nagurney, written for the Special 50th Anniversary Issue of Networks, Networks 77(1): (2021), pp 50-65.

Friday, November 26, 2021

My Talk at the Managing Disaster Risk: A Way to Sustainability Workshop in Nepal

This past week I had the pleasure of speaking at the Managing Disaster Risk: A Way to Sustainability Workshop organized by NEGAAS (Nepal Germany Academic Association). Speakers and participants joined virtually from multiple continents. 

My presentation was entitled, “Labor and Supply Chain Networks: Insights from Models Inspired by the COVID-19 Pandemic.” 

After a very warm introduction and welcome by Professor Tanka Nath Dhamala, I thanked him and co-organizer Professor Urmila Pyakurel, as well as Er. Ravi Khanal and the Nepal German Academic Association (NEGAAS) and its Program on Migration and Diaspora for the invitation to speak.

In my presentation,  I first emphasized that the COVID-19 pandemic is a healthcare disaster that unlike, natural disasters, even those exacerbated by climate change, is not limited to time and space and has affected virtually the entire globe. I spoke about research on perishable and time-sensitive supply chain networks that I had done with collaborators even before the pandemic that enabled us to pivot to produce relevant research in the pandemic. Among the applications of such supply chains are: food supply chains as well as pharmaceutical and vaccine ones. Such supply chains were especially impacted in the pandemic. 

I discussed a stream of publications that I had published in the pandemic on mathematical models, both optimization and game theory ones, that include labor as a critical resource in supply chains, along with labor availability and productivity. I first discussed, at a high level, the food supply chain network model introduced in Nagurney (2021a), in which there are bounds on labor associated with supply chain network economic links of production, transportation, storage, and distribution using a generalized network optimization framework to capture food product perishability. 

I then (cf. Nagurney (2021b) highlighted another optimization model in which there are distinct sets of bounds on labor - on links, or on a tier of supply chain activity, or on the entire supply chain network. Finally, I discussed a model and results in Nagurney (2021c), where a game theory model with multiple competing firms under various labor constraints are engaged in competition under profit-maximizing behavior. The governing concept in the case of bounds on labor on links is that of Nash Equilibrium, whereas in the case of the two other sets of constraints, in which the firms compete for labor (a reality in the pandemic), the concept is that of a Generalized Nash Equilibrium. Highlights of a case study on blueberries and migrant labor, which has suffered in the pandemic, was also presented.  This paper, published in the European Journal of Operational Research was recognized by a 2021 Editor's Choice Award.

In my talk, I also noted that it is important that firms pay laborers the wages that they deserve and this can actually give them a competitive advantage (cf. Nagurney (2021d)). I  further noted the benefits of cooperation, from a study (see Nagurney and Qiang (2020)), in which synergies associated with the teaming of humanitarian organizations in disaster response can be quantified. 

In my presentation, I emphasized the importance of research and publishing on disaster management but also the need to get the research out to the public. I noted the benefits of writing OpEds and speaking with the media as well as in working with legislators to effect positive change. Below are just some of the media that I have been interviewed for in the pandemic.

I concluded my presentation by describing how work on blood supply chains that I had written about in The Conversation has impacted  national policy in the US in the pandemic.

I very much appreciated the thoughtful comments and questions after my presentation.

The full slide deck of my presentation can be downloaded here.


Nagurney, A., 2021a. Perishable food supply chain networks with labor in the Covid-19 pandemic. In: Dynamics of Disasters - Impact, Risk, Resilience, and Solutions. I.S. Kotsireas, A. Nagurney, P.M. Pardalos, and A. Tsokas, Editors, Springer Nature Switzerland AG, pp 173-193. 

Nagurney, A., 2021b. Optimization of supply chain networks with the inclusion of labor: Applications to Covid-19 pandemic disruptions. International Journal of Production Economics, 235, 108080.

Nagurney, A., 2021c. Supply chain game theory network modeling under labor constraints: Applications to the Covid-19 pandemic. European Journal of Operational Research, 293(3), 880-891.

Nagurney, A., 2021d. Wage-dependent labor and supply chain networks in the COVID-19 pandemic and beyond. In press in: Analysis, Geometry, Nonlinear Optimization and Applications, P.M. Pardalos and T.M. Rassias, Editors, World Scientific Publishing, Singapore. 

Nagurney, A., Qiang, Q., 2020. Quantifying supply chain network synergy for humanitarian organizations. IBM Journal of Research and Development, 64(1/2), pp 12:1-12:16.

The program of the workshop can be viewed below.

The ideas generated at this workshop were fabulous and. A big plus was the mix of academics, practitioners, and representatives from government, which made for meaningful conversations.

Sunday, November 7, 2021

Had a Great Time Speaking at the Chancellor's Donor Appreciation Breakfast at UMass Amherst

Yesterday, I had the great honor of being the invited faculty speaker at the Chancellor's Donor Appreciation Breakfast at UMass Amherst.  This weekend was Homecoming Weekend, so that added to the festive atmosphere. Plus, this was the first time since the pandemic was declared that I was speaking to an audience (not including my class)  in person. There were about 300 in attendance and the event took place in the beautifully renovated Student Union. 

The program of the event is below.

It was wonderful to be seated with Chancellor Kumble Subbaswamy and student speaker Shelby Casimir plus a distinguished PhD alum, Dr. Sherwood, and his wife. My husband accompanied me.

The title of my presentation was: From Supernetworks to Supply Chains in the Pandemic.
The slide deck of my presentation can be downloaded here.

In my presentation, I spoke about amazing students and alums and also the inspiration for the Supernetworks book, and the establishment of the Virtual Center for Supernetworks 20 years ago.  I acknowledged Jack Smith Jr., who endowed the first chaired professorship that I held at the Isenberg School of Management, and also the Isenberg family. I was appointed the Eugene M. Isenberg Chair in Integrative Studies on April 14, 2021, a tremendous honor. Given the number of individuals that came up to me after the program, I believe that the audience enjoyed my presentation. I had hoped to inspire and to share my gratitude for the support!  And, of course, speaking about supply chains and our research on them in the pandemic is a passion of mine from the inclusion of labor to be able to quantify impacts of associated disruptions to our work on blood supply chains and influencing policy.  I also spoke about how much I have enjoyed writing OpEds in the pandemic to inform the public and decision-makers and how speaking to the media, whether for print, TV or radio has also enriched public discourse and outreach. 

Shelby Casimir and I enjoyed being photographed with the Chancellor (photo above). Shelby gave a very moving speech about the challenges of being a student in the pandemic and how she overcame the challenges. The Chancellor, as a super cheerleader of the university, spoke of the many accomplishments as well as major recent donations received.

It was wonderful to be entertained not only by a trio at the beginning of the breakfast and by a contingent of the famous UMass Marching Band towards the end.

It was extra special to see my Isenberg School colleagues, Vice Chancellor Nef Walker and Finance Professor Mila Sherman.
I acknowledged the leadership of the Isenberg School, including Deans Tom O'Brien, Mark Fuller, and, now, Anne Massey.

It was a truly memorable event enjoyed tremendously be all! The resilience of the faculty, administrators, staff, and especially students at UMass Amherst in the pandemic has been remarkable. We all gain from the great strength of the community at this outstanding research university.

Thursday, October 28, 2021

My INFORMS Tutorial on Game Theory and the COVID-19 Pandemic

This past week the INFORMS Annual Meeting took place in Anaheim, California with both in-person and virtual presentations. I was honored to have been invited by Professor John Carlsson from USC to present a tutorial at this conference. My tutorial was on: Game Theory and the COVID-19 Pandemic. The tutorials were all prerecorded and streamed.

The tutorial has coverage of fundamental methodologies plus applications of game theory and optimization to supply chain network models inspired by the COVID-19 pandemic from food to PPE ones. It includes models in which the governing concept is that of Nash Equilibrium, Generalized Nash Equilibrium as well as cooperation. The application part of the tutorial is based on papers, synthesized, that have been published in the pandemic. I am very grateful to my co-authors for wonderful collaborations before the pandemic and throughout the pandemic.

The video of the tutorial can be viewed here:

Due to requests, I have also made the slide deck of my tutorial available and it can be downloaded here:

Finally, the preprint of of the tutorial is available on the following link The tutorial paper, which is 48 pages, has been published in the INFORMS Tutorial volume:  Emerging Optimization Methods and Modeling Techniques with Applications

Special acknowledgments to Professors John Carlsson and Doug Shier of Clemson University for the expert editing of the volume and the organizing of these timely tutorials. 

Monday, October 18, 2021

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. 

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.

Tuesday, September 21, 2021

Teaching Face to Face in the Pandemic - The First 3 Weeks

It has been exciting, and quite interesting, to be back to teaching face to face at UMass Amherst in the pandemic.

When the COVID-19 pandemic was officially declared by the World Health Organization on March 11, 2020, I was on sabbatical for that spring term, and, hence, was not teaching.

Last academic year the instruction was done remotely, except for a few classes at the Isenberg School of Management. Hence, I taught all my courses in the Fall 2020 and Spring 2021 remotely via Zoom. It was a novel experience, especially since I had never taught online before. With the right technology, coupled with a lot of energy and creativity, the courses actually worked out quite well. A big plus was being able to host remarkable guest speakers, who are top professionals, in classes (and the speakers did not have to travel but could Zoom in even from Europe). 

The students regularly showed up to my Zoom office hours and I got to know many of them as individuals. Quite a few continue to stay in touch, even though they have now graduated!

UMass Amherst has a vaccination mandate (with exceptions for medical and religious reasons) for students, faculty, and staff, so that has provided some reassurance even with the Delta variant. Of course, there are still hundreds who are not vaccinated.

Also, UMass Amherst has a mask mandate inside buildings and students have to be masked in classes (although, strangely, faculty do not, and this has been bothering me a lot but this policy, to date, has not been changed). I am teaching with an N95 mask my Transportation and Logistics course.

It is very clear to me that students are glad that the instruction is now face to face. The first two lectures (I have now taught for three weeks) I reminded the students that the masks must be worn so that they cover their noses and mouths. If a student needs to drink, then the student should leave the classroom, and do so outside the room. The students have been truly wonderful at complying. They care about the health and safety of all and doing their best so that we can continue to have the university open and classes conducted in person.

Some features of  "remote" learning remain, which are actually positives. Assignments, lecture notes, and homeworks are all posted on Blackboard. This saves paper and the environment and the grades are easy to calculate but the "marking" of the homeworks can be challenging since it is much easier to write on paper. The students have gotten used to submitting homeworks online and this positive feature remains.

Also, and this is also advantageous pedagogically, when we were teaching (and learning) via Zoom, the classes were recorded and I would post the videos on Blackboard. Students, could then go back to review the material. This feature was very convenient and helpful.

Now, each of my classes (I had to have a classroom switch, due to several issues, including broken windows and technology that did not work) is recorded via Echo 360. I post the videos of the classes on Blackboard. Last year, I taught synchronously on Zoom and I liked the fact that we had a set schedule, which provided a nice rhythm to the week with the class meetings and also office hours. The students very much appreciated that the classes were "live" and not prerecorded (asynchronous teaching and learning).

I emphasize to the students that they must let me know if they will be missing a class and that is certainly happening in the pandemic. Having recordings of class meetings helps, but being healthy and in class is the best. The courses I teach are quite technical and having students ask questions while the class is in session can save a lot of time and enhances learning. 

I make sure that a window is open and the door to the classroom as well for ventilation since a layered approach to minimizing risk and contagion is important. Even the vaccinated can transmit the Delta variant so one has to be very careful.

So far, the teaching in person experience (once I got a new classroom) has been enjoyable and rewarding, despite it being the pandemic. 

I receive many "Thank you!s" after each class, which makes my day. I hope to instill the passion that I have for the subject in my students.

I am sure that this semester will bring new challenges, but, so far, I am feeling, more or less, "safe" and I love teaching my Transportation and Logistics class and interacting with the students in person.

Now, if only my PhD student had gotten his visa in time, so that he could be my TA. He is scheduled to arrive now in Spring 2020.

Monday, September 6, 2021

Our Research on the Inclusion of Labor into Supply Chain Networks

On this Labor Day, September 6, 2021, I thought it appropriate to write this blogpost in celebration of labor in the pandemic. Indeed, the COVID-19 pandemic has vividly and dramatically shown the importance of keeping our workers healthy and safe in all sectors of the economy from agriculture to healthcare. Many worked tirelessly and some suffered tremendously to ensure that products were produced, transported, and then consumed. Essential workers have become our heroes from farmers and food processors to freight service providers, including truckers, to healthcare workers, educators, and many others. 

During the pandemic, I have been researching how to include labor into supply chain networks so that disruptions could be better quantified, appropriate wages identified, and, even more recently, how firms should invest in enhancing the productivity of their workers through enhanced health and safety measures. This research continues and has become a great passion of mine.

I am pleased that three papers of mine on the inclusion of labor have now been published. The first paper, "Perishable Food Supply Chain Networks with Labor in the Covid-19 Pandemic," was published in the edited volume: Dynamics of Disasters - Impact, Risk, Resilience, and Solutions, I.S. Kotsireas, A. Nagurney, P.M. Pardalos, and A. Tsokas, Editors, Springer Nature Switzerland AG, 2021,  pp. 173-193. A prepint of it can be downloaded here.

The second paper, "Optimization of Supply Chain Networks with Inclusion of Labor: Applications to Covid-19 Pandemic Disruptions (2021),  was published in the International Journal of Production Economics, 235, 108080.

This IJPE paper continues to be among the most downloaded from the journal website over the past couple of months, which demonstrates the interest in this topic. This paper focused on the healthcare product supply chains, including PPEs.

The above two papers are optimization models and capture different types of constraints on labor availability. 

My paper, "Supply Chain Game Theory Network Modeling Under Labor Constraints: Applications to the Covid- 19 Pandemic (2021), was published in the European Journal of Operational Research, 293(3), 880-891. It proposes a series of game theory models in which competition for labor by firms is also considered. This is something that we are seeing in the COVID-19 pandemic, which has different sectors suffering from labor shortages. 

I was greatly honored that the Editors of this journal selected this paper of mine for an Editors' Choice Award and the publisher has made the paper available for free from the journal website.

I have also spoken at multiple conferences about this research; most recently, at the MOPTA Conference organized by Lehigh University, which I enjoyed very much. The title of my plenary talk at MOPTA was: "Labor and Supply Chain Networks: Insights from Models Inspired by the COVID-19 Pandemic."

The above papers all acknowledge and thank essential workers. And, today, I extend my gratitude to laborers world-wide.