Friday, November 27, 2009

urban and peri-urban sustainability policies

I find Kevin Kelly's writing a pleasure to read. Contrary to many who popularize science he has a deep understanding of current science thinking and an uncanny ability to extrapolate it and indentify questions that are yet to be addressed.

Recently, Andreas Lloyd has "remixed" Kelly's 1994 book entitled Learning from self-organizing systems in nature and technology. Lloyd has made Kelly's book much more accessible by removing, moving and editing the original. This has become a popular method in music. See for example my son's mixes on . [My son is Jordash]. Lloyd has adopted the method to writing.

In the final chapter Kelly raises and answers a question that sums up much of current deep science thinking.

"So how do you make something from nothing? From the frontiers of computer science, and the edges of biological research, and the odd corners of interdisciplinary experimentation, I have compiled Nine Laws of God governing the incubation of something from nothing. These nine laws are the organizing principles that can be found operating in systems as diverse as biological evolution and SimCity. Of course I am not suggesting that they are the only laws needed to make something from nothing; but out of the many observations accumulating in the science of complexity, these principles are the broadest, crispest, and most representative generalities. I believe that one can go pretty far as a god while sticking to these nine rules:

§ Distribute being

§ Control from the bottom up

§ Cultivate increasing returns

§ Grow by chunking

§ Maximize the fringes

§ Honor your errors

§ Pursue no optima; have multiple goals

§ Seek persistent disequilibrium

§ Change changes itself.

You can download and read the entire book for free at Once you read the book, ask yourself what policy and planning measures should be promoted to advance urban and peri-urban sustainability.

Thursday, November 26, 2009

The Stan Czamanski prize for best paper by a young regional scientist

I have been around Regional Science since my early high-school days in Philadelphia. Some kids of the Philadephia I-O table research team were employed during the summer vacation as "research assistants". We wore NASA name tags and felt proud that our salary was paid by NASA.

Many of the small group of people who called themselves regional scientists at the time are no longer with us. I find it rather sad. Walter Isard, the father of the field and Stan Czamanski are still around. Walter is a few month younger than Stan.

I was very sorry to hear that Walter did not attend the November meeting of the RSA. It was a first. The founding generation is no longer present at the conferences and soon their impact on the organization will be forgotten.

Stan just turned 91. I decided to mark the occasion by organizing a young scholar prize in honor of my father. The prize will be awarded during the annual meeting of the Israel RSA organization in January. So, if you are presenting a paper at that meeting and you are a young scholar who recently completed her PhD, please submit you paper for consideration to the organizing committee.

Sunday, November 1, 2009

Entrepreneurship, innovation and more

I just came across the following short video clip about the resilience and dynamism of the Israeli economy and the societal driving forces behind it: The video is a promo for a book entitled Start-up Nation: The Story of Israel's Economic Miracle.

It raises a vast number of hypotheses concerning entrepreneurship and innovation in Israel. While some of the assertions explaining the record breaking performance of Israel's economy seem correct, there is a need to perform an empirical analysis. In particular, cross-sectional data within Israel could provide counter-intuitive evidence.

I recommend the book.

Tuesday, October 27, 2009

Sprawl should be studied at various spatial resolutions

Yesterday was the first meeting of our workshop on peri-urban dynamics at the Technion – Israel Institute of Technology. It was intellectually stimulating to spend several hours with colleagues from Haifa, Tel Aviv and Ben-Gurion universities and our past and present grad students. There were geographers, experts in geo-spatial modeling, ecologists, urban planners and of course an urban economist.

We discussed the edge dynamics of cities and considered what is known about sprawl. The consensus around the room was that most of the literature relied on low resolution spatial data to identify and characterize sprawl. At best, the results are uninformative. The required characterization of sprawl should be in terms of the dynamics of natural systems within and at the edge of cities. In other words, when we think of sprawl we should model the urban system from the perspective of the dynamics of natural systems. Various resolutions should be considered. For avian population dynamics 3D porosity of cities is of interest.

At the workshop I presented some of our recent survey: Czamanski, D., Benenson, I., Malkinson, d., Marinov, M., Roth, R., Wittenberg, L., "Urban Dynamics and Ecosystems" in International Review of Environmental and Resource Economics, 2, 2008, pp. 1-45.

I cannot wait unitl our next meeting in Tel Aviv in two weeks.

Monday, October 26, 2009

The Great Cities in History

The Wall Street Journal published a brief review of John Julius Norwich's edited book that tries to identify cities that " played illustrious roles in the world's story". The title of the book is The Great Cities in History.


"There are 68 cities here included (if we count ancient Constantinople and modern Istanbul as separate cities). Each is accorded a short chapter, written by contributors whose number includes Simon Schama (on Amsterdam and Washington), A.N. Wilson (on London) and Jan Morris (on New York). The cities under discussion range from the primordial Uruk to modern monsters like Sao Paulo, taking in, along the way, a host of conurbations from the ancient, the medieval and the early modern periods".

I always wondered what makes a city great. I will look forward to reading this book on my next trip.

Saturday, October 24, 2009

urban porosity

Urban sprawl has been around for ever. Reading recent contributions on measuring this phenomenon [e.g. Elena G. Irwin, Nancy E. Bockstael and Hyun Jin Cho, "Measuring and modeling urban sprawl: Data, scale and spatial dependencies" or Charles Jaret, Ravi Ghadge, Lesley Williams Reid and Robert M. Adelman, "The Measurement of Suburban Sprawl: An Evaluation".] I became interested in urban porosity. While sprawl is primarily a phenomenon of the urban edge, to describe it and to explain it, there is a need to understand the dynamics of cities as 3D physical objects.

As a preliminary step, there is a need for rules that will enable us to observe cities and to describe the extent and nature of porosity. I have been reading S.T. Hyde, S. Andersson, K. Larsson, Z. Blum, T. Landh, S. Lidin and B.W. Ninham, The Language of Shape, Elsevier, (1997) and Michael Burt's PERIODIC SPONGE SURFACES AND UNIFORM SPONGE POLYHEDRA IN NATURE AND IN THE REALM OF THE THEORETICALLY IMAGINABLE. I must admit that it is unclear to me where to go next. Any ideas?

At the same time, we are making a bit of progress in formulating the structural relationships that should be at the heart of the relevant modeling effort. See Czamanski, D., Roth, R., “Characteristic time, developers’ behavior and leapfrogging dynamics of high-rise buildings" forthcoming in Annals of Regional Science, 2009.

Wednesday, October 21, 2009

A new method for measuring and studying cities

Hernan D. Rozenfeld, Diego Rybski, Jose S. Andrade Jr., Michael Batty, H. Eugene Stanley, and Hernan A. Makse are among the leading scholars of urban phenomena today. They just published an important paper entitled "Laws of Population Growth".

The importance of the paper is in the effort of the authors to go beyond stylized facts and to introduce some precision into the measurement of urban phenomena. What we know about cities is very much influenced by the way we mark the boundaries of cities and the way that we collect data about cities. For the most part cities are defined as administrative and governmental units. In reality, cities extend beyond such boundaries. Often a city spans several municipal units.

To overcome the obvious problems of traditional data collection, the authors "introduce a new method to designate metropolitan areas, denoted “City Clustering Algorithm” (CCA). The CCA is based on spatial distributions of the population at a fine geographic scale, defining a city beyond the scope of its administrative boundaries".

By applying this measurement method they find scale-invariant properties which they "modelled using long-range spatial correlations between the population of cells". This leads to the implication that "strong development in an area attracts more development in its neighborhood and much beyond. A key finding is that small places exhibit larger fluctuations than large places. The implications for locating activity in different places are that there is a greater probability of larger growth in small places, but also a greater probability of larger decline".

You can find this paper at: Http://

Saturday, October 17, 2009

A Joint Workshop in Peri-Urban Spatial Dynamics

During the academic year 2009-2010 Prof. I. Benenson (Tel-Aviv University), Prof. D. Czamanski (Technion - Israel Institute of Technology), Dr. D. Malkinson (University of Haifa) and Dr. Nurit Alfasi (Ben-Gurion University) will lead a year-long workshop that will explore the spatio-temporal interactions among urban, ecological and agricultural systems in the peri-urban zone.

The workshop will meet every two weeks, alternating between the Tel Aviv University and the Technion campuses. The meetings will take place on Mondays between 16:00 and 19:00. The first meeting is scheduled for the 26th of October, 2009 at the Technion.

Participants in the workshop will include senior researchers, graduate students and post-docs.

We intend to use this blog to exchange ideas raised in the workshop.

You are invited to comment and participate in these discussions through this blog.

The 2010 Advanced Geographical Analysis and Modeling Workshop

The increasing availability of geographic information and new spatial models originating in physics, economics and regional science, pose a challenge and present an opportunity for Geographic Information Science.

The Modeling Geographical System and the Geographic Information Science Commisions of the International Geographic Union would like to invite you to participate in a workshop that will be an exciting opportunity to explore with other scholars issues related to geospatial analysis and modeling. The workshop precedes IGU 2010 Regional Conference.

The workshop will take place on July 8th-10th, in Neve Ilan, located approximately 20km west of Jerusalem.

We look forward to seeing you at the workshop and encourage you to submit papers for presentation at the meeting.

Further details at:

Regional Science and Complexity Sessions at ERSA 2010 Congress

Following the complexity sessions in Liverpool in 2008 and in Lodz in 2009, the local organizing committee of 2010 ERSA Congress has given a green light to organize similar sessions in the coming meeting in Jönköping, Sweden (19-23 August 2010).

The Regional Science Association (RSA) is a natural venue to explore spatial phenomena by means of ideas from statistical mechanics concerning micro-behavior and macro-states. While such analyses have been around for some forty years now, dynamic simulation in Regional Science is relatively new. This is despite the obvious analogies of economies as self-organizing, emergent systems. Recently, research in the spirit of the New Economic Geography has illustrated the emergence of the urban patterns from some very basic economic principles. Heretofore a major obstacle to a fruitful dialogue among these disciplines has been the intention of regional scientists to reproduce reality and the aim of statistical physicists to capture the essence of phenomena, making the explanation "simple as possible, but not simpler". It is our presumption that there is a possible meeting point that can be identified and that lies at some mid-point between the real and the essential. Again at the 2010 European RSA we intend to explore the possibility of finding this meeting point among regional scientists and physicists. We think that the joint exploration of this topic by statistical mechanics and regional science can be interesting and fruitful.

By means of this letter I would like to invite you to participate in these sessions by contributing a paper. Come to explore with other scholars the growing dialogue among physicists, economists, geographers, planners and regional scientists concerning spatial phenomena. We are issuing this invitation almost a year before the meeting hoping that we can receive commitments early and so that we may be able to organize a book that will include the papers to be presented at the meeting. The deadline for the abstracts is 31 December 2009.

Please send your abstract as soon as possible to Danny Czamanski at

Sunday, July 5, 2009

Kevin Kelly on cities and nature

In his thoughtful and interesting blog "The Technium" Kevin Kelly addressed the question why people migrate to cities [see].

Kelly ponders, cities

"…seem like machines eating the wilderness, and many wonder if they are eating us as well. Is the recent large-scale relocation to cities a choice or a necessity? Are people pulled by the lure of opportunities, or are they pushed against their will by desperation? Why would anyone willingly choose to leave the balm of a village and squat in a smelly, leaky hut in a city slum unless they were forced to?"

One of the repercussions of the search for urban opportunities and rural quality of life is the formation of rural-like suburbs and the outward spread of cities. We wrote in the past about the leap-frogging spatial dynamics that results [Benguigui, L., Czamanski D. and Marinov, M., “City Growth as a Leap-Frogging Process: an Application to the Tel Aviv Metropolis” in Urban Studies, 38(10), 2001, pp. 1819 – 1839].

I am concerned that stylized facts and observation of cities at an inappropriate resolution leads to wrong conclusions concerning the impact of cities on nature. In fact we do not know enough about this interaction. In a recent paper we reviewed the little that is known [Czamanski, D., Benenson, I., Malkinson, d., Marinov, M., Roth, R., Wittenberg, L., "Urban Dynamics and Ecosystems" in International Review of Environmental and Resource Economics, 2, 2008, pp. 1-45]. A tentative conclusion from our review is that sprawl is a contributor to biodiversity and not destroyer of nature. Our research group is engaged in a multi-year empirical study of this phenomenon.

Saturday, July 4, 2009

young and old cities

Before long I will be teaching again my urban economics course. I started to re-read my lecture notes and the new papers that were published in the last 12 months.

I am deeply disappointed with the way my fellow professional urbanists view cities and the prescriptions that they conjure up to cure urban ills that may or may not exist. My disappointment stems from the clear dissonance between what continues to be published in the professional literature and evidence. Thus for example, cities are said to expand outwards like sea waves in all directions. They are not supposed to leave any un-built areas in their wake. Open spaces within and around urban areas are thought to be a relic of early urban evolution. The truth is quite different.

Like the proverbial seven blind men, we see cities partly and imprecisely. I would like to persuade my students to see cities from a non-traditional perspective. It is my intention to provide them with a distant, and yet close, perspective and to change the way they think about their home.

There are two fundamental problems with the way that professionals have been looking at cities. Their vision is obscured by the use of statistical data. The information they use is granular and their chunky data display only that which statistical units reveal. Census bureaus and other government producers of statistics view cities through a prism that "divided" cities into statistical areas and gather data accordingly. Statistical areas are relatively large. Within such relatively large area there are many buildings, activities and people. They display a great diversity of things. In official statistics, each statistical area provides a distorted, average, image of the activities within it and the city as a whole is seen as an average of these averages. The vast diversity that characterizes real cities at the very local neighborhood level is simply lost. Therefore, the stylized facts about cities do not reflect their reality.

The representation of a phenomenon by its average occurrence can be innocuous only under very special circumstances. The average can represent the population in cases that the number of extreme occurrences is very small relative to the average-size cases and that the number of extremely large and extremely small events is similar. Such populations are termed "normal", or Gaussian.

The world of cities is not Gaussian. It is characterized by fat tails. For example, in very few countries is the population of cities very large. The vast majority of cities have small populations. Very many other urban characteristics display the same fat tail distribution. Indeed, it is almost an universal characteristic of cities.

In the least, large and small cities do not represent the same phenomenon. It is as if we were to understand human physical activities by means of a typical individual. Abilities, performance and repercussions for kids, young people, middle-aged individuals and for old people would be seen as equivalent. Obviously, the stylized facts and reality would be disparate. So it is with cities. There young cities and old cities, etc. Cities possess characteristic times and we need to understand them in a dynamic context and not through still, Polaroid-like, photographs.

There are very many other implications of fat tail distribution of city sizes. Perhaps the greatest distortion that results from the use of such data is our understanding of sprawl and its repercussions. But, on this I will write later.