What a Great Regional Science Conference in Miami

The regional science conference in Miami was a great success.

I especially enjoyed the sessions organized in honor of Professor Walter Isard, the founder of regional science, who passed away several months ago.

The venue at the Hyatt Regency hotel was perfect as well as the style of the conference, which included a discussant for each paper presentation.

I enjoyed speaking about our work on medical nuclear supply chains as well as on the dynamics of predator-prey ecological networks as nature's supply chains (and their relationship to classical spatial price equilibrium problems as well as to multitiered supply chain network equilibrium problems).

It was wonderful to see so many of my wonderful regional science colleagues from around the world at this conference -- there were many hugs and catching-up conversations.

Many thanks to the organizers for such an intellectual feast.

As for Miami, the warmth of the climate as well as the people, plus the gorgeous sights (the hotel is in downtown Miami but there are parks along the water a monorail and amazing skyscrapers) will be hard to leave.

Why do I live in Massachusetts -- perhaps I forgot to include weather as an amenity in my utility function?

My previous trip to Miami was a decade ago -- my first flight and conference after 9/11 and it was to the INFORMS conference.

I am now heading to INFORMS Charlotte, which should be fabulous, as well.

I will be posting many photos after I return to Amherst.

Spatial Price Equilibrium and Food Webs -- Supply Chains in Nature

I continue to be fascinated by networks in nature and have been conducting research at the interfaces of economics, ecology, and operations research.

Specifically, I became intrigued by the underlying economics of predator-prey relationships in complex food webs, which are nature's supply chains.

This research has led to the paper, "Spatial Price Equilibrium and Food Webs: The Economics of Predator-Prey Networks," in which we establish that the governing equilibrium conditions underlying predator-prey interactions with multiple species correspond to the classical spatial price equilibrium conditions dating to the work of the Nobel Laureate in Economic Sciences, Paul Samuelson!

To be able to establish the equivalence between systems in ecology and in economics, as we have done, suggests an inherent commonality among entirely distinct network systems and demonstrates that interactions in ecology and biology can be interpreted economically with price functions and transportation / transaction cost functions. Another fascinating aspect of ecological networks and food webs is that nodes correspond to different species but the flows are common and correspond to biomass flows. So, such networks are single commodity ones!

Our research included the development of a dynamic model of predator-prey interactions using projected dynamical systems theory, a theory and methodology which we developed, and which is now being used in evolutionary game theory by, among others, Bill Sandholm. I just purchased his book and am enjoying reading it. Economists (and others) are fascinated by evolutionary game theory, which has origins in biology, notably, in the work of Maynard Smith. I am delighted that our work has relevance here, as well.

Our paper is to appear in the Proceedings of the 2011 IEEE Conference on Supernetworks and System Management. This conference takes place in Shanghai next week.

Professor Paul Samuelson -- Rest in Peace and Reflections

The news just arrived that Professor Paul Samuelson, the Nobel Laureate, and Professor Emeritus of Economics at MIT, has passed away at the age of 94. This obituary highlights some of his immense achievements, from being the first winner of the Bates Medal to being the first American to receive the Nobel Prize in Economic Sciences. Professor Samuelson was still writing and publishing in his 90s.

I remember meeting Professor Samuelson in person while I was a Visiting Scholar at the Sloan School at MIT. I had corresponded with him and had been sending him some of my papers since I was doing (and still am) work in spatial economics. His 1952 paper, "Spatial Price Equilibrium and Linear Programming," published in the American Economic Review, I have cited dozens of time. I especially appreciated his ability to use and apply the appropriate methodological techniques for model formulation and analysis in economics. Also, that paper even identified the beautiful bipartite network structure of this classical problem.

One of my favorite reminiscences of Paul Samuelson was riding in the elevator with him at the Sloan School and we would also meet up in either the first floor snack shop or on the top floor dining room at which I (and those who visited me) enjoyed both the buffet lunch and the great views of the Charles River. Professor Samuelson was always well-dressed with one of his bowties on and although he was a giant in scholarship, height-wise, I could look him in the eyes. One day, as we were riding the elevator together he said to me, "Anna, have you proven any good theorems lately?" and that statement still resides with me.

Coincidentally (and life is filled with coincidences, it seems), yesterday, I was in Cambridge, in Harvard Square (Harvard is where Samuelson received his PhD and his nephew is the former President of Harvard, Larry Summers). A great friend of mine, Professor Kei May Lau, was visiting from Hong Kong. She had given, the day before, a seminar at MIT and I could not miss up the opportunity to see her and to reminisce. Little did we know then that we would be hearing about Harvard and MIT again today through the death of Paul Samuelson.

Above I have included a photo taken yesterday in Cambridge, which, somehow to me, captures something special. I include it as a small memorial to Professor Paul Samuelson, to his brilliance, and to his legacy.