Sunday, October 31, 2010

Freight as the Weakest Link in the Chain

I travel a lot by plane, train, automobile, and/or bus and frequently write on this blog about my travel experiences. In my writings I have also commented on my air travel experiences and lack of security at distant airports. In my research, I assess network systems, in particular, those in transportation and logistics, including supply chains, from their efficiency to their vulnerability. A recent study of ours: "Fragile Networks; Identifying Vulnerabilities and Synergies in an Uncertain Age" highlights the system-wide aspects of network performance and the negative impact of disruptions as well as total link failures.

The events over the past couple of days in which cargo shipments, originating in Yemen, were found to contain explosive devices, which could have brought down airplanes, have further highlighted the importance of checking cargo.

As reported in the article, Mail Bombs Highlight Flaws in Systems for Screening Air Freight, in today's Boston Globe: "If you talk to anybody senior at airports, they will tell you freight is the weak link in the chain." This quote by Chris Yates, an aviation security specialist, is literally on target.

As for the facts reported in the article:

  • Approximately 60 percent of all cargo coming into the United States is on passenger planes with the remainder of about 40 percent arriving on cargo planes.
  • About 50,000 tons of cargo is shipped by air within the United States every day, with approximately 25 percent of that shipped by passenger airlines.

One particular vulnerability in the system: Trusted companies that regularly do business with freight shippers are allowed to ship parcels as “secure’’ cargo that is not automatically subjected to further checks.

Some countries such as England already have heightened and thorough cargo security checks which delay shipments up to 24 hours but offer safety and piece of mind. Here we see multicriteria decision-making in action -- counterbalancing cost vs. time vs. safety/security.

Read the terrific article in the Boston Globe by Gregory Katz and ponder what else besides the passengers and crew may be on that plane with you as you circle the globe.

Saturday, October 30, 2010

An Auto Executive and Former Student Comes Back

I think that everyone remembers one's first day on the job.

As a professor, I still remember teaching my first classes at UMass Amherst in the School of Management. I was hired, fresh with my PhD in Applied Math with a specialty in Operations Research from Brown University, and with several years of high tech work experience in the defense sector in Newport, Rhode Island, to teach MBA courses in Management Information Systems and Management Science.

One of the classes that I was responsible for teaching was a night class in Holyoke, Massachusetts. Several of the students in that class were over twice my age and doubted my credentials, so I even brought my Brown PhD diploma to show them.

In that class was a student who stood out with his energy, enthusiasm, and ambition. Plus, he was close to my age so there was a natural comfort level between us. He was trying to get into the MBA program while working as a bagger for a local food store and the then MBA Director told him that he would need to evaluate his performance in 3 courses before considering him for full-time admission. One of the courses was the course that I was teaching.

Well, he made it, received his MBA, got a terrific position with a Big Three auto company (which is profitable even today) and has moved stellarly through the ranks with assignments in NYC, Philly, Cincinnati, Detroit, the DC area, and, my favorite -- in Dallas, Texas (which was considered an international assignment because Texas is just so different from the rest of the US).

Now my former student has reached the position of Director with responsibilities for North America and he came back yesterday. We spent two hours at lunch reminiscing and catching up and his stories of transportation and business were captivating (and the time much too short).

We ended on such a high note -- he had me doubled over laughing as he regaled me with stories of all the UMass Amherst alums he comes across in his business and how they remember fondly their experiences on this campus, with its student and faculty diversity and numerous activities and events, which prepared them really well for survival and excelling in the real world.

We walked back together from lunch since I had to take part in a teleconference and he was going to meet his child, who, yes, is now a student at UMass Amherst.

Friday, October 29, 2010

New Director of NSF and New Interim Dean of Engineering at MIT who is in Operations Research!

While in Washington DC this past Monday, I heard that it is now official that Dr. Subra Suresh, the former Dean of Engineering at MIT, has been sworn in as the new Director of the National Science Foundation (NSF).

MIT issued a nice press release, complete with a photo of the swearing in ceremony of Dr. Suresh with his wife present.

I had written about Dr. Suresh's nomination earlier in this blog
and about the Acting/Interim NSF Director, Dr. Cora Marrett.

Also, while in Washington, I speculated with a few colleagues that Dr. Cynthia Barnhart would "take over" Dr. Suresh's position as the Dean of Engineering at MIT. She has been appointed, in fact, as the Interim Dean of Engineering.

Kudos to Dr. Barnhart, former President of INFORMS -- a wonderful scholar in transportation and in operations research, a terrific human being and role model, and a member of the National Academy of Engineering!

Coincidentally, I will be on a panel with Dr. Barnhart at the upcoming INFORMS National Meeting in Austin Texas, November 7-10, 2010.

The panel, quite appropriate, is entitled: Balancing Work and Life.

Professor Barnhart visited us at the Isenberg School at UMass Amherst when she spoke in our Speaker Series.

Congratulations to both Dr. Suresh and Dr. Barnhart on their new major leadership roles!

The President of MIT, Dr. Susan Hockfield, is a female and now the Interim Dean of Engineering is also a female! Perhaps the permanent one will be, as well.

Thursday, October 28, 2010

Isenberg Graduate Students Excel in Award-Winning Student Chapter

The Isenberg School at UMass Amherst has issued a press release on the award that our INFORMS Student Chapter will receive on November 9, 2010 at the INFORMS Conference in Austin, Texas.

Our student chapter will be honored for the fourth year in a row with a national award from INFORMS for its activities. This year we will be receiving the magna cum laude award.

As Faculty Advisor to this terrific group of students, I could not be happier for them. They accomplish so much professionally and socially through teamwork, dedication, and innovation.

Last year's President of the student chapter, Min Yu, who is a doctoral student in Management Science, and also my student, will be joining me in Austin, Texas to receive the award on behalf of our chapter.

For the full press release click here.

The UMass Amherst INFORMS Student Chapter website can be accessed here.

Even today, on a gorgeous Fall day, this group of students will be hosting a ping pong tournament, complete with pizza, refreshments, and prizes! A former member, Thomas Lenk, who happens to be visiting Amherst from Germany will take part!

Tuesday, October 26, 2010

The Serendipity of Travel

One of the best parts of travel is the people that one meets.

In my previous blogpost, I wrote that I was off to Washington DC to serve on a proposal review panel.

When I approached my gate at Bradley airport, this past Sunday, I was greeted by a hello from one of my colleagues, Professor Lisa Masteralexis, who is the chair of the sports management department at the Isenberg School, and her husband. They are both experts in sports law and were returning from a wedding in New Jersey, which they said had been lovely.

On my flight from Bradley to Reagan National, I had the distinct privilege and pleasure of being seated next to one of the top lawyers in the country who is a senior partner of an international law firm based in NYC. Coincidentally, he had just been to a board of trustees meeting of the school in western Massachusetts that my daughter attends and that he and his daughter are alums of. He was flying to DC to give two presentations on corporate governance.

We spoke of mutual friends, what is special about the school that he is on the board of, and about Harvard since he is an alum twice over and I told him about my experiences as a Radcliffe Fellow the year that the then Dean, Dr. Drew Gilpin Faust, became the new President of Harvard.

Our flight arrived 20 minutes early so we had to wait on the tarmac before our gate was available which gave us just enough time to close the conversation on a really pleasant note. Another common point was the enjoyment of taking the train from Westchester to NYC, which is his commute now to work and which was a special treat for me while growing up in Yonkers.

The panel in DC was a success and I got to see some colleagues and make new acquaintances. Plus, the weather in DC was simply glorious and I take full credit for bringing it back with me to Amherst. But the highlight of the trip was meeting the fascinating lawyer on my flight down.

Sunday, October 24, 2010

Off to Washington DC!

As an academic, my busy professional life is filled with research, teaching, and professional service activities. I often write on this blog about research and about teaching -- this post is about service.

The service activities that an academic may be involved in (let's say some do not engage in much service) take on numerous forms -- from internal service, that is, departmental, school-wide, and university service -- to professional service, which may require travel. The latter involves reviewing journal articles, serving on editorial boards, serving on society committees, on conference organizing committees, and other activities. I receive, on the average, requests to review 3 papers a week and professional service alone could keep me with a full workload if I were to accept everything that came my way.

(Note: much of the service that we do as faculty is "pro bono" and we do not get paid extra for it but it is essential to maintaining the integrity and sustainability of our disciplines and their growth and sustenance.)

Service also involves taking part in peer-review panels and in evaluating different proposals for funding. I have reviewed proposals for scientific agencies in Canada, Sweden, Hong Kong, New Zealand, Denmark, and Ireland, to name just a few. Also, I review proposals for scientific agencies in the U.S.

I will be out of town shortly to serve on a scientific review panel. Preparation entails reading thoroughly and carefully a pile of proposals and writing drafts of the evaluations. This takes place even before the face-to-face meeting and discussions with other panelists. Getting together in the DC area, where many of the major funding agencies (the National Science Foundation, the National Institutes of Health, the Department of Energy, etc.) are located and where the panels are convened, to see colleagues and to meet new ones, is always enriching intellectually. There are times of the year (Fall, late Spring and early Summer) during which the Washington DC area is quite beautiful; plus, several times during my flights to/from DC I have sat next to Congressmen, which always makes for stimulating conversations.

My suitcase is packed, my briefcase filled with proposals and my reviews, and I am looking forward to another trip to Washington DC!

Of course, my classes are covered, and when I return, I will be grading piles of midterm exams!

Saturday, October 23, 2010

Congrats to All the Student Chapter Award Recipients of INFORMS!

I would like to congratulate all the recipients of this year's INFORMS student chapter awards! The award ceremony will take place on Tuesday morning, November 9, 2010, in Austin, Texas at the 2010 INFORMS annual conference.

Special thanks go to the officers of the student chapters as well as the Faculty Advisors who work very hard in organizing activities and disseminating information about operations research and the management sciences. As the Faculty Advisor to the UMass Amherst INFORMS Student Chapter, I know the dedication that is required to have a successful student chapter. 32 INFORMS student chapters submitted their annual reports for 2009 and the awards below are to recognize the leading chapters for their activities.

The message below is from Dr. Stefan Karisch and was distributed today to the Faculty Advisors and the chapter presidents.

Dear Student Chapter Officers,

Congratulations! The Chapters/Fora Committee is pleased to notify you that your chapter is a winner of the INFORMS Student Chapter Annual Award at the level shown below. The purpose of these awards is to recognize the achievements of student chapters. The award will be presented at the Chapters/Fora Breakfast at the upcoming INFORMS Annual Meeting in Austin. If you are at the meeting, we hope you will join us and be recognized at this event. If not, we will mail the award to you.

Best regards,

Stefan Karisch

INFORMS VP Chapters/Fora

Summa Cum Laude

Arizona State University

Magna Cum Laude

University of Massachusetts

University of South Florida

Cum Laude

Texas A&M University

North Carolina State University

University of Illinois - Chicago

Florida International University

University of California - Berkeley

Oklahoma State University

University of Alabama

Stefan E. Karisch
Director, Operations Research and Optimization

Quality and Business Operation Services

A Boeing Company

ph: 303.328.6389 | Mobile : 303.305.8388 | fax: 303.328.4117 |
55 Inverness Drive East | Englewood, CO 80112 |

Wednesday, October 20, 2010

Panel on Disaster Recovery and Mitigation Planning and Resilience

I have accepted an invitation to be on the Disaster Recovery and Mitigation Planning and Resilience panel that will take place at the Transportation Research Board (TRB) meeting January 23-27, 2011 in Washington, DC. This will be the 90th annual TRB meeting and about 10,000 transportation professionals from around the world are expected to attend!

This panel is sponsored by the Planning and Environment - Group; the Policy and Organization - Group, and the Committee on Critical Transportation Infrastructure Protection.

The motivation for holding such a panel is as follows. Transportation systems throughout the world are greatly affected by natural disasters and human-created events. These systems are critical for daily activities and the economy. The magnitude of the U.S. transportation infrastructure makes protecting it extremely challenging and costly. This special session highlights innovative approaches to disaster recovery planning and assesses improving transportation infrastructure resilience to extreme events.

Joining me on the panel will be Jeffrey L. Western, Western Management and Consulting, LLC, Rae Zimmerman, New York University, and Herby Lissade, California Department of Transportation, with Pamela Murray-Tuite, Virginia Polytechnic Institute and State University, presiding. I know both Professors Zimmerman and Murray-Tuite and am very much looking forward to this very timely panel and to the TRB meeting!

The title of my panel presentation: Building Resilience into Fragile Transportation Networks in an Era of Increasing Disasters.

The TRB is one of six major divisions of the National Research Council, which serves as an independent adviser to the federal government and others on scientific and technical questions of national importance, and which is jointly administered by the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

According to the TRB website: The mission of the Transportation Research Board is to provide leadership in transportation innovation and progress through research and information exchange, conducted within a setting that is objective, interdisciplinary, and multimodal. The Board is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation.

Last year, my most recent PhD student, Dr. Patrick Qiang, received the Charles V. Wootan award from the Council of University Transportation Centers at the 2010 TRB meeting for his doctoral dissertation. The book that we co-authored: Fragile Networks: Identifying Vulnerabilities and Synergies in an Uncertain World, John Wiley & Sons, 2009, was noted in TR News last year.

Friday, October 15, 2010

Institute for Information Infrastructure Protection (I3P) Meeting at MITRE

After teaching my undergraduate class in Transportation & Logistics this past Wednesday, I was picked up by Dr. Kevin Fu of the CS Department at UMass Amherst (who also taught his undergrad class that morning) and we headed to the Institute for Information Infrastructure Protection (I3P) meeting that was taking place at MITRE in Bedford, MA.

I3P is a consortium of academic institutions, government labs, and nonprofit organizations that focuses on information infrastructure protection. This consortium is led by Dartmouth College. Its new Research Director, Dr. Shari Pfleeger, formerly of Rand, assumed this position on September 1, 2010. She is terrific and very knowledgeable and dynamic.

UMass Amherst is a member and Dr. Fu is the rep from UMass while I have been appointed the alternate. The member map is available here. The talks and brainstorming sessions were terrific over the past two days as were the many conversations that took place during the breaks and at the dinner Wednesday night at the Bamboo restaurant (simply magnificent).

I personally very much enjoyed meeting with consortium members from the University of Idaho, the Idaho National Laboratory, Indiana University, the University of Tulsa, Carnegie Mellon University, the U.S. Military Academy at West Point, SRI International, Cornell University, Dartmouth College, and MITRE. When you get a group of very engaged and smart researchers together, the intellectual discussions are very rewarding and exciting. Also, one can't beat face -to-face communications.

You can find more information on the I3P here.

I was pleased to see my research on transportation, the Braess paradox, and the wisdom of crowds featured in the September 2010 issue of I3P Researchers in the News.

Wednesday, October 13, 2010

U.S. Technology Helps in the Rescue of the Chilean Miners

As the world watches the miners in Chile get rescued one by one and marvels at their incredible survival and teamwork since being trapped on August 5, 2010, we have to give credit to U.S. technology with Plan B Turning Out to be Fastest Path for Rescue.

According to The New York Times: “To tell you the truth, I don’t think anyone had a whole lot of faith in us,” said Brandon Fisher, president of Center Rock, a company in Berlin, Pa., that supplied the Plan B drills. “They didn’t understand the technology.”

Mr. Fisher and others lobbied the Chilean government to let them use the drills, known as downhole hammers, which have air-powered bits that pound the rock as the drill rotates. The other two drilling operations used more conventional bits that work through rotation only.

This technology was also used to drill ventilation shafts and other holes to help the 33 trapped miners, who are now being pulled out through a shaft, one by one, via a capsule, from half a mile beneath the earth.

The Chilean government and its people should also be applauded for their dedication and extraordinary efforts in this unparalleled rescue!

I wish all the trapped coal miners happy times with their families and friends and a full recovery. Both of my husband's grandfathers were coal miners in Pennsylvania and my college room-mate at Brown University was from Chile so my family has been following closely the evolving events surrounding this major news story of human endurance and the technology, faith, and support that are making this rescue possible.

Tuesday, October 12, 2010

Outsourcing in Supply Chains Under Exchange Rate Risk and Competition

Offshore outsourcing refers to the practice of procuring goods or services from outside foreign suppliers rather than producing them in-house. Since outsourcing manufacturing to lower-wage countries generally reduces production costs it has been growing rapidly in the past decade. From 2000 to 2007, 70 percent of U.S. non-oil import growth was driven by imports from developing countries with imports from China alone accounting for 39 percent of the growth.

However, although offshore outsourcing can provide significant cost reduction opportunities, it also exposes supply chain firms to various risks including: foreign exchange risk, production disruption risk, quality risk, supplier default risk, etc.

Among these risks, foreign exchange risk is consistently considered to be on the list of top concerns of supply chain executives! A study by The Economist, which surveyed 500 global company executives with responsibility for risk management, showed that, in 2009, exchange rate uncertainty was ranked as the second most important risk factor next to demand uncertainty due to the economic recession. In addition, the executives ranked foreign exchange risk as their number one concern for the subsequent twelve months. In 2010, the high volatility of the euro and possible appreciation of the Chinese yuan have posed significant risks to many companies involved in offshore outsourcing and global trades.

In a recent study, completed with Professor Zugang Liu, we quantified the impact of foreign exchange rate uncertainty and competition intensity on supply chain firms who are involved in
offshore outsourcing activities. In particular, the computer-based, analytical model that we developed considers firms' decision-making regarding pricing, material procurement, offshore-outsourcing, transportation, and in-house production under competition and foreign exchange rate uncertainty. Our model allows firms to have different attitudes toward risk. Through a series of simulation examples, we were able to answer imortant questions regarding supply chain firms' pricing and outsourcing decisions, and the associated profits and risks.

The simulation results indicate that, in general, the risk-averse firm has lower profitability and lower risk than the risk-neutral firm. When the competition intensity increases, the exchange rate risks of both risk-neutral and risk-averse firms will increase, which is consistent with recent empirical findings; the profit of the risk-averse firm will always decrease; and the profits of the risk-neutral firm will decrease if exchange rate uncertainty is relatively low and will increase if exchange rate uncertainty is high.

On the other hand, when exchange rate volatility increases, the average profit of the risk-neutral firm will first increase and then become stable while the profits of risk-averse firms will always decrease. As exchange rate variability increases, the risk of the risk-neutral firm will always increase, and the risk of the risk-averse firm will increase when the firm increase prices to compensate the risks, and will decrease if the firm switches from outsourcing to in-house production.

Moreover, as the exchange rate variability becomes higher the risk-averse firm will reduce its outsourcing activities while the risk-neutral firm may increase its outsourcing activities. These results explain the phenomenon regarding how exchange rate uncertainty affects imports of developed countries.

The results in our study provide timely managerial insights for supply chain decision-makers involved in offshore outsourcing and in this highly competitive economic climate:

1. Supply chain managers should first evaluate the risk tolerance level of the firm. If the firm is more concerned about risk, it should try to differentiate its products from that of its competitors since intense competition will both reduce profitability and increase the risk.

2. They should also maintain certain in-house production capacity for operational hedging purposes when the exchange rate uncertainty is high.

3. For the firms that are not sensitive to risk, high exchange rate uncertainty may provide an opportunity for them to get an edge on the competition with more risk-averse firms. For example, when the exchange rate variability is relatively high they should expand their outsourcing operations in order to gain more market share from more risk-sensitive competitors which may help them increase average profits. However, the firms that exploit these opportunities should understand that such strategies can also cause significant risk and loss.

More background, information, and data, along with the model and computational procedure, which was utilized for the simulation examples, can be found in our paper, "Supply Chain Outsourcing Under Exchange Rate Risk and Competition," by Zugang Liu and Anna Nagurney.

Monday, October 11, 2010

The 2010 Nobel Prize in Economic Sciences Announced

I watched the live streaming from Stockholm (with the preceding countdown) of the announcement of the 2010 Nobel Prize in Economic Sciences.

The recipients this year, for their work in markets with search frictions (think of buyers and sellers trying to find one another or as my husband says, "E-bay"), are: Peter Diamond of MIT, Dale Mortensen of Northwestern University, and Christopher Pissarides of the London School of Economics. The former two are Americans whereas Pissarides is a British-Cypriote.

Last year, one of the recipients of the Nobel Prize in Economic Sciences was the first female recipient of this prize in 40 years, Elinor Ostrom!

Congratulations to this year's Nobel laureates!

While I was at MIT (under the sponsorship of an NSF Visiting Professorship for Women and then a UMass Amherst Research Fellowship Award) I took a short course from Peter Diamond and enjoyed it a lot. He was surprised that I was in the audience and told me that I was publishing on the course topics but I told him I always want to learn more.

Last January, I had the privilege of being invited to speak at the Symposium on Transportation Network Design and Economics at Northwestern University in honor of the visit of Martin Beckmann, the co-author of the landmark 1956 book, Studies in the Economics of Transportation, who had been on my dissertation committee at Brown University.

I am sure that this year's Nobelists in Economics will be celebrating with their families, friends, colleagues, and students as well as with their staff and administrators at their universities!

In December, the gala dinner and awarding of all the Nobel prizes for 2010 will take place in gorgeous Stockholm, Sweden, one of my favorite cities.

Saturday, October 9, 2010

Businessweek Recognizes Our Outstanding Operations Management Major at the Isenberg School

Businessweek has now recognized the Operations Management (OM) program/major at the Isenberg School at UMass Amherst as one of the top programs in this specialty for 2010!

Click here for the full list of OM program rankings for 2010.

To make it to the top 25 (actually, we are number 21) speaks to the excellence of the education that our students are receiving.

But education is a two-way street, and the students that our major attracts are amazing and a joy and a privilege to teach.

Background on the determination of the Businessweek rankings in OM and other business specialties is available here.

Our students benefit from a rigorous core curriculum in business and take foundational courses in Management Science, Operations Management, and Quality Management. They select electives in such topics as: Transportation & Logistics (which I teach), Supply Chain Management, Simulation, Forecasting, Business Process Optimization, and Advanced Operations Management.

With recent faculty hires, we are even offering a course in Cybertechnology!

As for what our recent graduates are doing now?! Some are working in exciting startups, others in established well-known retail companies and high-tech companies, while others have positions in logistics and even in government and in the military.

Several of our OM majors have worked for prominent consulting firms and have gone on to receive their MBAs from Harvard or a PhD from MIT.

No matter where their life journeys take them, the critical thinking, problem-solving, and analytical skills that our Operations Management majors acquire, coupled with excellent communication and writing skills, will serve them well. Plus, with the variety of student clubs that we have at the Isenberg School, there are numerous opportunities for our students to assume leadership and officer positions, to travel and to live abroad, to take on wonderful internships, and to engage themselves in community service projects.

Thank you, Businessweek, for recognizing our truly terrific Operations Management program at the Isenberg School!

Thursday, October 7, 2010

A Genius Rides the Acela Alone

The title of the OpEd piece in today's New York Times caught my eye: "The Seat Not Taken."

Then I saw that it was written by John Edgar Wideman, who had been on the faculty at UMass Amherst, where I teach, and, upon "retirement," joined the faculty of Brown University, my alma mater. You can find our "connections" on the Provost's page at UMass Amherst.

The OpEd piece was haunting and painful for me to read so I had to write about it since it moved me very much.

John Edgar Wideman is a Fulbright scholar, a MacArthur Fellow (considered to be a genius award), and an author of acclaim who has received numerous awards and honors for his writings.

In the OpEd
, he writes how during his commutes from DC to Providence, Rhode Island, where Brown University is located, via the Acela train, the seat next to him is often vacant.

He writes: I’m a man of color, one of the few on the train and often the only one in the quiet car, and I’ve concluded that color explains a lot about my experience. Unless the car is nearly full, color will determine, even if it doesn’t exactly clarify, why 9 times out of 10 people will shun a free seat if it means sitting beside me.

I would give anything to be able to sit next to him for the 6 hour ride on the Acela from DC to Providence or from Providence to DC to just be able to talk to him!

In the transportation & logistics class that I am teaching this semester the students and I often exchange our travel stories around the world and we have especially noted some magnificent train rides (including some high speed ones) that we have taken in Europe. We have even discussed such dreams as highspeed rail throughout the US. How painful that someone of the stature of a John Edgar Wideman feels ostracized while riding the Acela in the US!

By the way, his daughter, Jamila Wideman, who graduated from our local high school, Amherst High, and then went on to captain the Stanford University women's basketball team and then played for the WNBA, was just last week honored by the high school. She is now a lawyer and works in NYC.

Mark Newman Speaks on Networks at UMass Amherst

I attended a very enjoyable colloquium yesterday in the physics department at UMass Amherst given by Professor Mark Newman of the University of Michigan and the Santa Fe Institute.

The title of his talk was: Epidemics, Erdos Numbers, and the Internet: The Structure and Function of Complex Networks

Abstract: There are networks in almost every part of our lives. Some of them are familiar and obvious: the Internet, the power grid, the road network. Others are less obvious but just as important. The patterns of friendships or acquaintances between people form a social network; the species in an ecosystem join together to form a food web; the workings of the body's cells are dictated by a metabolic network of chemical reactions. As large-scale data on these networks and others have become available in the last few years, a new science of networks has grown up, drawing on ideas from physics, math, engineering, biology, and other fields to shed light on systems ranging from bacteria to the whole of human society. This talk will examine some new discoveries regarding networks, how those discoveries were made, and what they can tell us about the way the world works.

I had hosted Professor Newman several Octobers ago, when Professor David Parkes and I organized an Exploratory Seminar on Dynamic Networks at the Radcliffe Institute for Advanced Study at Harvard, so it was nice to see him back in Massachusetts.

Some of the network images that he used in his talk yesterday are available here.

His audience yesterday was comprised of physicists, engineers, and computer scientists and yours truly (plus some folks I could not name nor did I know their backgrounds).

His talk (with a wonderful delivery and enthusiasm) focused mostly on network structure, whereas my research focuses on a wide spectrum of networks where flows and user behavior matters, in addition to network structure, from supply chains to transportation networks and the Internet as well as economic and financial networks and electric power networks. He mentioned food webs which I could relate to since my work in network economics is being applied to fisheries. I told him afterwards that I would like to see more work in social networks that includes flows (as the work that I did with my former doctoral student, who is now a Professor, Dr. Tina Wakolbinger, does).

Also, as I tell my students, we in operations research/management science and even in economics can trace the literature on the subject even back to the mid1800s! Networks in terms of model formulations, applications, and even methodologies and algorithms have been major topics of scientific research especially beginning with the 1950s and beyond. The fascination with networks and novel applications have made the subject seem "new" to some and especially to disciplines, who have more recently discovered networks and are applying tools from their disciplines to their study.

Sustainable Fashion Supply Chain Management Under Competition and Brand Differentiation

In an earlier blogpost, I wrote about our recent work in fashion supply chain management and in sustainable supply chain network design.

I am pleased to announce that one of my doctoral students, Min Yu, and I have completed a study of sustainable fashion supply chain management. In the study, which is documented in our research paper, we developed a modeling framework that captures competition in fashion supply chains in the case of differentiated products with the inclusion of environmental concerns. The model assumes that each fashion firm's product is distinct by brand.

Each fashion firm seeks to maximize its profits and to minimize the emissions that it generates throughout its supply chain as it engages in its activities of manufacturing, storage, and distribution, with a weight associated with the latter criterion. The model allows for alternative modes of transportation from manufacturing sites to distribution centers and from distribution centers to the demand markets, since different modes of transportation are known to emit different amounts of emissions.

The competitive supply chain network model advances the state-of-the-art of fashion supply chain modeling in several ways:

1. it captures competition through brand differentiation, which is an important feature of the fashion industry;

2. it allows for each firm to individually weight its concern for the environment in its decision-making, and

3. through a general network framework, alternatives such as multiple modes of transportation can be investigated.

In our paper, we also presented a case study, in which, through a series of numerical examples, we demonstrated the effects of changes on the demand price functions; the total cost and total emission functions, as well as the weights associated with the environmental criterion on the equilibrium product demands, the product prices, profits, and utilities. We noted that the environmental weights could also be interpreted as taxes and, thus, in exploring different values an authority such as the government could assess a priori the effects on the firms' emissions and profits.

The case study also demonstrated that consumers can have a major impact, through their environmental consciousness, on the level of profits of firms in their favoring of firms that adopt environmental pollution-abatement technologies for their supply chain activities.

Wednesday, October 6, 2010

President of Amherst College to Lead the New York Public Library

Dr. Anthony "Tony" Marx, the President of Amherst College, is expected to be approved today to head the New York Public Library. This news was reported in today's New York Times as well as in our "local" paper, the Daily Hampshire Gazette.

************An Update -- It is Now Official*******************
Dr. Marx will step down from his Presidency of Amherst College on June 30, 2011 to become President of the New York Public Library, with approval of the board.

Dr. Marx is the product of NYC's public schools and holds advanced degrees, including his PhD, from Princeton University. His wife is a Professor at Columbia University. He is a wonderful father and, in fact, just Monday night at a dinner for parents (his son and my daughter attend the same school), our tablemates were discussing how the 5 College System, which includes UMass Amherst, Amherst College, Smith College, Mount Holyoke College, and Hampshire College, provides wonderful resources for our community in western Massachusetts.

Speaking of previous heads of the New York Public Library, Dr. Vartan Gregorian, served as President of the New York Public Library, and then became President of Brown University, my alma mater. Now he heads the Carnegie Corporation.

We wish Dr. Tony Marx the best in his very exciting new position in NYC!

Now, who will take over as President of Amherst College?!

Sunday, October 3, 2010

Experiential Marketing and the Negation of the Braess Paradox with the Wisdom of Crowds

I enjoyed reading the recent blogpost by the Texas-based marketing firm, bloomfield knoble, that discussed how waiting times during events such as visits to museums, amusement parks, and even to Vegas casinos should be manipulated to garner the best experiences for customers/clients. And speaking of Las Vegas, Adam Nagourney writes in the NYTimes that it needs help!

bloomfield knoble connected waiting times (think of standing in line to get to what you really want to do) in the context of marketing experiences with the Braess paradox, which identifies a situation where a new route, when added, under user-optimizing or selfish behavior, may result in an increase in travel time for all.

I was pleased that in bloomfield knoble's post my most recent work on the subject proving that the Braess paradox will be negated under a suitably high demand was also noted so that there is a wisdom of crowds phenomenon taking place.

The post also recognized that such paradoxes can occur in other types of networks (and not just in transportation ones), a related topic that I have done a lot of research on.

Coincidentally, recently, while teaching my Management Science graduate class I shared the story with my students about how one can reduce the perception of onerous waiting times by making the experience of waiting more pleasant. Those of us in this area of research and practice enjoy recalling how the waiting times for elevators to arrive can be reduced -- just add mirrors to the outer doors so that people can admire themselves and, perhaps, one another, and time will go by "faster." The same holds for how queues in banks or amusement parks can be designed or in playing music while customers are waiting for some service (but recognizing that not everyone has the same taste in music).

Friday, October 1, 2010

2010 Ig Noble Prizes Announced at Harvard

The annual awarding of Ig Noble prizes at Harvard (not to be confused with the Nobel prizes) is always very entertaining and fun. The ceremony took place yesterday and 5 (real) Nobel laureates, including Professor William Lipscomb (whose son was a classmate of my husband's) gave out these awards.

This year there are some terrific ones in transportation, management, engineering, and economics so enjoy the full list, which was reported on already in The Guardian and in The Chronicle of Higher Education.

My favorite "winner" on this year's list, which I had written about a few months ago on this blog, and noted that the researchers had not cited earlier relevant literature in transportation, was on:

Transportation planning: Toshiyuki Nakagaki of the Future University-Hakodate, in Japan; Kentaro Ito of Hiroshima University; Kenji Yumiki, Ryo Kobayashi, Atsushi Tero, Seiji Takagi, Tetsu Saigusa, all of unidentified institutions; and Dan Bebber and Mark Fricker of the University of Oxford, "for using slime mold to determine the optimal routes for railroad tracks." (Paper: "Rules for Biologically Inspired Adaptive Network Design," Science, January 22, 2010.)

Actually, some of the out-of-the-mainstream ideas can be quite brilliant. For example, my work in Network Economics is now being applied to complex food webs and fisheries.

And the recipient for:

Management: Alessandro Pluchino, Andrea Rapisarda, and Cesare Garofalo, all of the University of Catania, Italy, "for demonstrating mathematically that organizations would become more efficient if they promoted people at random." (Paper: "The Peter Principle Revisited: A Computational Study," Physica A, February 2010.)

Coincidentally, I was a Fulbright Senior Specialist in Business Administration at the University of Catania in Italy in 2008 and together with my collaborator there, Professor Patrizia Daniele, we organized a workshop on complex networks.