Saturday, June 29, 2013

Google Reader Doomsday

If you follow Urban Demographcis via our Twitter or Facebook page, you don't need to bother with this post. However, if you read this blog using any RSS Feed Reader, this post may be useful*. 

[Image Credit: Feedly]

As you likely know by now, Google is shutting Google Reader down on July 1fst. Tyler Cowen has pointed out to a list of alternative options, showing that there's Life after Google Reader (no need to panic). By the way, I have tested myself a few of those alternatives (NewsBluer, Flipboard, FeddlerRSS, The Old Reader and Feedly). I'm sticking with Feedly, at least for a while.

Additionally, I'm not sure how Google Reader shutdown will affect the 'blogosphere' because some RSS readers are dependent upon Google Reader to work. Besides, it migh break a couple of links I have posted in the past. Anyway, here is our RSS feed, just in case you need to re-subscribe to this blog.

Based on previous experience though, things will sort themselves out.

* If you have the habit of reading blogs and websites AND you don't know what a RSS Feed Reader is....then you should consider taking 5 minutes of your time to learn how it works. It can give a big boost to your productivity  procrastination .

Thursday, June 27, 2013

A universal model for mobility patterns

This is one of the best papers I have read in the last few years. Neat stuff! 

Simini, F; Gonzalez. MC; Maritan; A; Barabasi, AL. (2012). A universal model for mobility and migration patterns. Nature 484, 96–100. (ungated link)

Introduced in its contemporary form in 1946, but with roots that go back to the eighteenth century, the gravity law is the prevailing framework with which to predict population movement, cargo shipping volume and inter-city phone calls, as well as bilateral trade flows between nations. Despite its widespread use, it relies on adjustable parameters that vary from region to region and suffers from known analytic inconsistencies. Here we introduce a stochastic process capturing local mobility decisions that helps us analytically derive commuting and mobility fluxes that require as input only information on the population distribution. The resulting radiation model predicts mobility patterns in good agreement with mobility and transport patterns observed in a wide range of phenomena, from long-term migration patterns to communication volume between different regions. Given its parameter-free nature, the model can be applied in areas where we lack previous mobility measurements, significantly improving the predictive accuracy of most of the phenomena affected by mobility and transport processes.

ps. I've postponed this post for far too long because I was planning to start a study with some testing on the radiation model using Brazilian data (commuting, migration, national flights). However, I might face some (good!) turbulence in my professional/academic life in the next few months and I don't know when I'll get time for that.

Commuting landscapes (Fig 4)
[Image Source: Simini et al, 2011]

Sunday, June 23, 2013

Urban Picture

What world cities would look like at night with no light pollution?
A project by Thierry Cohen.

Rio de Janeiro

San Francisco



São Paulo

Saturday, June 22, 2013

Fertility and Mortality estimates for small areas in Brazil

It is really nice to see an increasing number of good studies/publications written by/with Brazilian demographers. Here are two recent papers that might be of interest for some readers.

A few more papers:

International Migration Outlook 2013

Friday, June 21, 2013

City's skyline from memory

What if you could draw a city's skyline from memory? Amazing work by Stephen Wiltshire (via hypeness)

[Click on the images to enlarge them]





Thursday, June 20, 2013

Today Will Be Bigger

One more post about the recent events in Brazil. This is probably one of the most exciting/moving moments of the protests in front of Brazil's National Congress in Brasília (17/06/2013).

Zero-fare public transport is one of the major  infeasible  demands. Apart from the emotional turmoil, Leo Monasterio reminds us that congestion pricing and free parking are little spoken about by the protesters.

Wednesday, June 19, 2013

About the recent protests in Brazil

"As many as 200,000 people have marched through the streets of Brazil's biggest cities, as protests over rising public transport costs and the expense of staging the 2014 World Cup have spread. […] The protests are the largest seen in Brazil for more than 20 years." 
The recent protests in Brazil are receiving a wide and somewhat heterogeneous coverage from the international media. The best piece I have read is this one from The Economist. It gives a broad and sensible idea of what is in stake.

I’d also like to share two studies  self-promotion alert : the first study shows a marked rise in urban bus fares over the recent decades in Brazil (the Portuguse version has been published in a peer-reviewed journal - ungated link here); the second study shows a detailed analysis on household expenditures on public and private transport in Brazil (this one is written in Portuguese only but it has an Abstract in English).

[Sad but still funny... Image credit: Turkish grandma]

ps. I’m not going to write my opinion on the recent protests in Brazil for two reasons. First, I have mixed feelings about it. I’m proud and at the same time confused not knowing what to expect. Second, from the beginning I’ve decided this would not be an opinion blog because it would demand from me two things I don’t have: strong opinions and ability with words.

Related Links:

Friday, June 14, 2013

Latin American Cohabitation Boom 1970-2007

This week we had the visit from Prof. Toni Lopez here at Ipea, who gave us a very nice workshop on IPUMS (I'll write a post about IPUMS later). Toni also presented a paper he and colleagues published last year at PDR. Here is the paper :

ESTEVE, Albert; LESTHAEGHE, Ron; LOPEZ-GAY, Antonio (2012) The Latin American Cohabitation Boom, 1970-2007, Population and development review, 38- 1, pp. 55–81

The article describes the rise of unmarried cohabitation in Latin American countries during the last 30 years of the twentieth century, both at the national and regional levels. It documents that this major increase occurred in regions with and without traditional forms of cohabitation alike. In addition, the striking degree of catching up of cohabitation among the better-educated population segments is illustrated. The connections between these trends and economic (periods of high inflation) and cultural (reduction of stigmas in ethical domains) factors are discussed. The conclusion is that the periods of inflation and hyperinflation may have been general catalysts, but no clear indications of correlation were found between such economic factors and the rise in cohabitation. The shift toward more tolerance for hitherto stigmatized forms of conduct (e.g., homosexuality, euthanasia, abortion, singleparent household) is in line with the rise of cohabitation in regions of Argentina, Chile, and Brazil where cohabitation used to be uncommon. Further rises in cohabitation during the first decade of the twenty-first century are expected in a number of countries (e.g., Mexico) despite conditions of much lower inflation.

Figure 2 - Patterns in the rise of the share of cohabitation among all unions of women aged 25–29 in regions of Latin American countries, various censuses 1970–2000
[click on the image to enlarge it]

Assorted Links

  1. 1955 Map with No-Go Zones for Soviet Travelers in the U.S. (via The Map Room)

  2. Abandoned Star Wars Sets

  3. Travel in London Report 5 - 2012 (via David Metz)

  4. Guardian university league table 2014

  5. Braveness

  6. How Long Are Songs? 

  7. A Global City Mash-Up

  8. Puzzling Brazilian city names - one in every nine Brazilian municipalities is named after a Catholic saint (e.g. São Paulo). By the way, Brazil has over 5,565 municipalities.  (via @scharlab)

Tuesday, June 11, 2013

Map of the Day

Mapping all geotagged tweets since 2009 (Every dot is a Tweet, and the color is the Tweet count). More cities here (via WB Data Viz).



São Paulo

North America

Monday, June 10, 2013

The size of bike-sharing systems Worldwide

A couple of years ago we have posted a map comparing some subway systems at the same scale. Based on a similar idea, David Yanofsky has made a very nice map comparing the size of 29 bike-sharing systems around the world. He has used data from an excellent work by Oliver O’Brien with interactive maps including all those cities.


ps. I saw this at Dug's blog (Map of the Week), where he has gathered other interesting visualizations of bike sharing systems*.

[Image Credit: David Yanofsky]

* Related Links:

Sunday, June 9, 2013

Venn Diagrams and Regression Analysis

Prosa Econômica (a Brazilian econ blog) has written a nice post (Part 1 and 2) on how to use the Venn diagram to teach regression analysis. A walk in the park!

This idea is discussed in a 2002 paper by Peter E. Kennedy. You may read the paper here.

* I saw this at Bernardo L Queiro'z twitter!

Friday, June 7, 2013

"Thinking in terms of space rather than place"

A few comments by Chris Bertram (Crooked Timber) on Brasília (ht Pedro Souza)

"As a new city, built on the red highland earth in the 1950s, Brasilia incorporates all the best town-planning theory of that era. [...] Apparently, nobody had the idea that the people staying in hotels might want to see anything other than more hotels …"

ps. The title of this post is actually a quote by Robert Hughes.

Growth and change in metropolitan form

The City Form Lab (SUTD/MIT) has a research project on measuring urban expansion, particularly focused in East Asia. They have recently published the 'Progress report on urban form and land use measures'. After scanning the report, I'm definitely adding it to my reading list.

[Image Credit: SUTD City Form Lab]

Thursday, June 6, 2013

ALAP's new Blog - ICPD Beyond 2014

The Latin American Population Association (ALAP) has launched a new Blog [written in Spanish] where the'll be covering several demographic and development related issues. 

It's intened to be a preparation to the discussions that will follow during the 2014 ICPD (International Conference on Population and Development), aka Cairo+20. (via Demografia Unicamp)

Tuesday, June 4, 2013

Geographies of world university rankings

Jöns, H, Hoyler, M (2013) Global geographies of higher education: The perspective of world university rankings, Geoforum, 46, 45-59.

This paper contributes to emerging debates about uneven global geographies of higher education through a critical analysis of world university rankings. Drawing on recent work in geography, international higher education and bibliometrics, the paper examines two of the major international ranking schemes [...]. Our analysis illustrates how the substantial variation in ranking criteria produces not only necessarily partial but also very specific global geographies of higher education. In comparison, these reveal a wider tension in the knowledge-based economy between established knowledge centers in Europe and the United States and emerging knowledge hubs in Asia Pacific. An analysis of individual ranking criteria, however, suggests that other measures and subject-specific perspectives would produce very different landscapes of higher education.

[Image Credit: Jöns and Hoyler, 2013)]