Monday, December 30, 2013

When Social Networks meet Public Transport

Among the Best Scientific Visualizations of 2013 (by Brandon Keim), one particular paper attracted my attention as the authors analyze the encounter network of bus passengers in Singapore. Here is the paper:

[image credit: Sun et al, 2013]

Understanding metropolitan patterns of daily encounters." By Lijun Sun, Kay W. Axhausen, Der-Horng Lee, Xianfeng Huang. Proceedings of the National Academy of Sciences, Vol. 110 No. 34, August 20, 2013.

Understanding of the mechanisms driving our daily face-to-face encounters is still limited; the field lacks large-scale datasets describing both individual behaviors and their collective interactions. However, here, with the help of travel smart card data, we uncover such encounter mechanisms and structures by constructing a time-resolved in-vehicle social encounter network on public buses in a city (about 5 million residents). Using a population scale dataset, we find physical encounters display reproducible temporal patterns, indicating that repeated encounters are regular and identical. On an individual scale, we find that collective regularities dominate distinct encounters’ bounded nature. An individual’s encounter capability is rooted in his/her daily behavioral regularity, explaining the emergence of “familiar strangers” in daily life. Strikingly, we find individuals with repeated encounters are not grouped into small communities, but become strongly connected over time, resulting in a large, but imperceptible, small-world contact network or “structure of co-presence” across the whole metropolitan area. Revealing the encounter pattern and identifying this large-scale contact network are crucial to understanding the dynamics in patterns of social acquaintances, collective human behaviors, and—particularly—disclosing the impact of human behavior on various diffusion/spreading processes.

Friday, December 27, 2013

Urban Picture


[image credit: ? via Earth Pics]

Tuesday, December 24, 2013

Happy Holidays

A couple of centuries ago, a man was born who changed the course of history. Happy Birthday Isaac Newton!

[image credit: ?]

In the spirit of Christmas, I have two gifts to share with my hundreds of thousands of readers out there:

A song, by Ali Farka Toure:

And a short video about Christmas:

Sunday, December 22, 2013

2013 World Population Data Sheet

Here is the PRB's 2013 World Population Data Sheet. You may also take a look at their webinar or this interactive infographic highlighting some key population trends.  More of the same 

Chart of the Day

Wednesday, December 18, 2013

Peer effect + Neighborhood effect

The interaction of Peer and Neighborhood effects of Bart Simpson, aka 'The Cone of Ignorance' (via FlowingData).

[Image Credit: FlowingData]

Monday, December 16, 2013

Waiting for the traffic light in Germany

As Tyler Cowen would put it: "The culture that is Germany".

Sunday, December 15, 2013

Urban Picture

Manhattan (1944), by Andreas Feininger.


Bonus: Central Park

[Image Credit: ? via @GoogleEarthPics]

Thursday, December 12, 2013

Equity Issues in Transport Policy

As some of you may know, I have just started my PhD and I will be focusing on 'Equity Issues in Transport Policies' with bits of spatial and demographic analysis.

So I was very glad to watch this short talk by Enrique Peñalosa (former mayor of Bogota): 'Why buses represent democracy in action'. You know, it's always good to hear big names saying you're working on important problems.

Tuesday, December 10, 2013

The Geography of Nobel Prize winners

Using Online images to map urban perception

Ricardo Dagnino emailed me months ago! a link to a very inventive research project that uses online images and crowdsourcing to map urban perception. The project is called Place Pulse and it is conducted by Cesar Hidalgo and his colleagues at the MIT Media Lab.

Here is how the research method works and the project webpage . By the way, take one minute to support the project with some clicks.

And here is one paper they published this year: 

The Collaborative Image of The City: Mapping the Inequality of Urban Perception, by P. Salesses, K. Schechtner and C. Hidalgo. published at PLOS one

ps. They have a Video Abstract.

Monday, December 9, 2013

Urban Modelling back in 1976

The other day I was wandering in the library when I bumped into the book Urban Modelling: Algorithms, Calibrations, Predictions, published by M. Batty back in 1976 (!). Since then, he and his team at CASA have made many contributions to the field of urban studies with new modelling developments and applications.

Some of the softwares developed at CASA (including GMap Creator) are available for download here. You can play with your own Von Thunen Model!

[Image Credit: CASA]

Related Links:

Thursday, December 5, 2013

Personalized Doodle

Today I got my first Personalized Doodle!

It took me a few minutes to understand that my Google frontpage was actually celebrating my birthday and not someone else's. Those guys at NSA Google are doing a great job!

[Thanks NSA Google]


Wednesday, December 4, 2013

Sunday, December 1, 2013

Biographical note: a visit to Leviathan

Quite often, I'm amazed at how old Oxford University is. My College (St Edmund Hall, aka Teddy Hall) dates back to the 13th Century and some of its oldest buildings date from the 12th and 17th centuries.

Last week, I took a short tour visit to the Old Library of my College to see the 1st edition of Leviathan, pubished in 1651 by Thomas Hobbes. My Social Scientists readers know how special this book is and you can probably imagine how I felt like a kid in a candy store!

ps. I thank the dedicated librarians at Teddy Hall who were very kind to receive me in their 'office' to talk about their work.

Assorted Links