Archive for March, 2012

[funny] inequality explained

Friday, March 30th, 2012



Level book

Diversity and The City: city size, density, and wealth

Friday, March 23rd, 2012

In the last few days, I had the opportunity to read quite a lot on social media, ubicomp, architecture, etc.  and found few papers studying the relationship between city density and citizens’ use of social media. So I thought it might be useful to report what Jane Jacobs wrote in her book “The Death and Life of Great American Cities” in 1961:

… it still remains that dense concentrations of people are one of the necessary conditions for flourishing city diversity. And it still follows that in districts where people live, this means there must be a dense concentration of their dwellings on the land preempted for dwellings.

She makes the distinction between density and overcrowding:

Overcrowding within dwellings or rooms, in our country, is almost always a symptom of poverty or of being discriminated against, and it is one (but only one) of many infuriating and discouraging liabilities of being very poor or of being victimized by residential discrimination, or both.

Warning 1: Overcrowding is not necessarily connected to density. Jacobs actually says that overcrowding might be more commonly seen in low-density areas. So number of dwellings per acre might be more informative.

Warning 2: City diversity is different than city wealth. The idea is that

city density contributes to city diversity: low concentration areas (suburbs) can only support businesses of the dominant culture, while cities can afford diverse businesses…

To sum up, the relationship wealth-density is a complicated one :)

Now, a couple of months ago, the bright minds behind The Economist Intelligence Unit published a very nice report  titled Hot Spots. In it, they build a competitiveness index for cities. Toward the end of the report (you can read it here), they add:

Cities of all sizes can be competitive, but density is a factor in the competitiveness of larger cities. The top ten most competitive cities in this ranking range from the world’s biggest (Tokyo’s estimated 36.7m people) to some of its smallest (Zurich’s estimated 1.2m). Indeed, there is no correlation seen between size and competiveness in the Index. While bigger cities offer a greater pool of labour and higher demand, as well as

potential economies of scale, if they are not planned correctly congestion and other issues can actively impede their competitiveness. Urban density is clearly linked to higher productivity: Hong Kong’s efficient density is one reason it performs far better in the Index than, say, Mexico City’s inefficient urban sprawl.

So the conclusion is:

So while size can bring advantages in terms of a city’s overall competitiveness, it will only do so if it is carefully planned. Greater density can help, although this isn’t necessarily the only solution. Overall, however, there is no clear correlation between absolute population size and overall competitiveness

p.s. This is an interesting post on density vs. Jacobs’ density.

p.s. Another interesting post on density vs. livability 

Telcos strategies: Failing, but not yet a failure

Wednesday, March 21st, 2012

This is a very old article on The Economist yet still relevant.

Hewlett-Packard … plans to scatter millions of sensors around the world … It is doing this to increase demand for its hardware, but it also hopes to offer services based on networks of sensors. For instance, a few thousand of them would make it possible to assess the state of health of the Golden Gate bridge in San Francisco, says Stanley Williams, who leads the development of the sensors at HP. “Eventually”, he predicts, “everything will become a service. Apple, though it prides itself on its fancy hardware, is already well on its way towards transforming itself

into a service and data business thanks to the success of its iPhone. …  Much of the innovation in this field may come not from incumbents but from newcomers, and it may happen fastest on such platforms as Pachube.

Likely. However, if one looks at the smart cities agenda, IBM got that a while ago. Telcos who invest billions in R&D haven’t |o|  They have still time to learn from the smarter kids on the block though ;)

- daniele (missing his technology electives at the business school)

sunbelt 2012

Monday, March 19th, 2012

Very interesting social network meet up: full of sociologists and full of jokes about physicists – jokes mostly by older folks. Those are my rough notes. I don’t have time to edit them… sorry ;)

- daniele (daniele tweeting)

(warning: i could not cover all presentations i attended).

Strategy and status in online dating (or: How to get a date online). Brilliant (super) brilliant talk by Kevin Lewis. He studied network data from a popular online dating site and looked at questions like “Who sends more or fewer messages to other dating site users? Who receives more or fewer messages? And who is more or less likely to respond to the messages they receive, and to receive responses to the messages they send? “. Very good work with a nice outcome – “gendered status hierarchies that characterize a given social structure”. A must read work.

Happiness as the Duality of Ritual and Belief: Mapping Buddhist Social-Cultural Identities. This was a really good talk! José A Rodríguez and John W Mohr presented their analysis of the process of becoming a Buddhist in a Catholic country (Spain) “by mapping the shared systems of meanings and repertoires of practice in a western Buddhist lay sangha.” They analysed beliefs and of practices by administering a survey with “detailed questions about their life styles, including fine-grained questions about religious beliefs (subsets of beliefs that reflect one’s Buddhist way of feeling and seeing) and the ensemble of practices that a person assembles.”

Concurrent Sex Partner Relations within Sexual Networks of Swingers. Fully packed room! Anne-Marie Niekamp “examined network indicators for the level of concurrency in the sexual ego networks of swingers predicting high potential of STI transmission”. Work with great potential!

Targeting Conflict with Social Network Balance. Ian McCulloh delivered a brilliant presentation in which he proposed “an approach based on balance theory and transitivity to identify non-intuitive centers of gravity to target and eliminate social conflict within an organization. The approach is demonstrated on three examples: a family in divorce, a team of intelligence analysts and information technologists operating in Iraq, and policy implications for the US war in Afghanistan.” He also compared the centrality of the same individuals in two networks centrality(hate net)/centrality(like net) ;)

The “Telefunken Code”: A technique for the collection of anonymized social network data on sensitive topics. This was a brilliantly delivered presentation. Travis Wendel presented a way to “anonymously” collect social network data (which is very important if one is collecting data about as HIV transmission, illicit drug distribution and the functioning of criminal organisations). Using this technique, they interviewed methamphetamine users and distributors in New York City. More specifically: “we asked each participant how many members of the target population’s cell phone numbers he/she knew; if the number

was five or fewer, we elicited information about all of them; if the number was greater, we elicited information about a random sample of five. We asked participants whether each of the last four digits of their (and network members’) cell phone numbers were odd or even, and from 0-4 or from 5-9 (generating the “Telefunken Code”).” In the future, they might ask for more digits, tackle the cognitive difficulty for understanding which number is odd/even, and understand the impact of prepaid (disposable) mobile plans.

To Broker, or Not: The Psychology of Bridge Decay. Eric Gladstone presented a very nice work on how brokers are perceived. They demonstrate that people perceive brokerage roles as relatively more advantageous relative to other network positions. However.. Participants in our studies saw these positions as burdensome, carrying the potential for significant cognitive overload and emotional stress. .. what is necessary to maintain one’s position as a bridge is likely to be detrimental to one’s reputation, which also may explain why the bridge decays over time. ” Here are the findings: 1) non-brokers were rated significantly more trustworthy than brokers; 2) non-brokers were chosen more often than brokers in a game that required trust (investment game); 3) brokers were chosen more often than non-brokers for a trivia game.

Risk, Uncertainty and Tie Strength by Paolo Parigi and Bogdan State. ” Although risk and uncertainty have long been recognized as fundamental factors impacting the formation of social ties, their close study has been confined to the lab. ” To fix that, they analysed data from They found “that ties formed in either high-risk or high-uncertainty conditions are stronger than those formed in no-risk or low-uncertainty circumstances. Uncertainty is not a significant predictor of tie strength when risk is inexistent, however. Our findings show, likewise, that highly-embedded ties are stronger, and that ties are stronger if they are embedded by stronger ties.”

Navigation in semantic memory. Nicole Beckage presented a very neat work on semantic networks (using florida free association norms [nelson et al. 1999]). she considered words being nodes and edges are directed and weighted based on frequency of response. and she looked at how individuals navigate from a starting location in the semantic network to a target word.

More talks (for hard-core readers) ;)