Monday, August 22, 2016

Monocentric and Polycentric cities as a continuum scale

In 2013, some colleagues and I published a paper in which we proposed the Urban Centrality Index (UCI). This index measures the centrality of a defined area (city, metropolitan area, region, country etc) considering a continuum scale that varies from extreme monocentric to extreme polycentric, and it can be applied to the spatial distribution of population, jobs, hospitals, economic activities in general etc.

I have recently shared on Github the script in R we have used to calculate UCI in our paper as well as the published study and working-paper versions. In case you're interested, here is the paper.

Pereira, R. H. M., Nadalin, V., Monasterio, L., & Albuquerque, P. H. M. (2013). Urban Centrality: A Simple Index. Geographical Analysis, 45(1), 77–89. doi:10.1111/gean.12002

This study introduces a new measure of urban centrality. The proposed urban centrality index (UCI) constitutes an extension to the spatial separation index. Urban structure should be more accurately analyzed when considering a centrality scale (varying from extreme monocentricity to extreme polycentricity) than when considering a binary variable (monocentric or polycentric). The proposed index controls for differences in size and shape of the geographic areas for which data are available, and can be calculated using different variables such as employment and population densities, or trip generation rates. The properties of the index are illustrated with simulated artificial data sets and are compared with other similar measures proposed in the existing literature. The index is then applied to the urban structure of four metropolitan areas: Pittsburgh and Los Angeles in the United States; São Paulo, Brazil; and Paris, France. The index is compared with other traditional spatial agglomeration measures, such as global and local Moran's I, and density gradient estimations.

Thursday, August 18, 2016

Rio in time-lapse 8K

Joe Capra (aka SCIENTIFANTASTIC) has one of the most seriously awesome time-lapse videos in high definition. Since were in Olympics season, here are two of his videos of Rio.

Best viewed in HD, fullscreen



ps. Here are some other great time-lapse videos we've posted before

Monday, August 15, 2016

Don't trust summary statistics

Always visualize your data! Wise words, by Alberto Cairo

Sunday, August 14, 2016

Playing around with (messy) GPS data of the bus routes in Rio using R

click on the image to enlarge it

Here is a snippet of the code I've used to create this plot in R using ggmap. I've also created a gist with a fully reproducible example of how to make flow maps in R using another dataset, in case you're interested.

Tuesday, August 9, 2016

Air quality in world cities by hour of the day

This comes from The Economist's Daily chart, where you can find other indicators and more information on the methodology (more here).

click on the image to enlarge it

Sunday, August 7, 2016

Urban transformations in the run-up to the Rio Olympics

The eviction of 77,000 favela residents to open space for the infrastructure investments in Rio, however, is also an important but less visible part of the city transformations. The guys at Rio on Watch (twitter) have been doing a good work in covering the negative impacts of the Olympics.

Apart from that, there has been an overload of interesting articles to read about the Olympics in Rio. For articles in English, I've been enjoying following Alex Cuadros, Brasil Wire, Juliana BarbassaSimon Romero and Jonathan Watts.

UPDATE: Vila Autodromo is one of the most affected Favelas by the Olympics as it sits literally next to the Olympic Park. The LA Times have just published a before-after photo of Vila Autodromo, showing how a big part of the favela has been transformed into a parking lot.

credit: Washing Post

Thursday, August 4, 2016

Next time you find yourself "too busy" to write ....

... remember that Barack Obama published a paper... in a high impact journal! (ht to my friend Nicolas Raab)

Obama, B*. (2016). United States health care reform: progress to date and next steps. JAMA. 316(5):525-532. doi:10.1001/jama.2016.9797.

* Author Affiliations: President of the United States, Washington, DC.

ps. I must confess I'm not the greatest example when it comes to abiding to deadlines though . Sorry supervisors !

Tuesday, July 26, 2016

The cost of every Olympics Games since 1960

Paul Kirby points out to a new working paper by Bent Flyvbjerg and colleagues where they make a systematic analyses of the costs and cost overruns for every Olympic Games between 1960 and 2016.

Flyvbjerg, B., Budzier, A., & Stewart, A. (2016). The Oxford Olympics Study 2016: Cost and Cost Overrun at the Games. Available at SSRN 2804554.

Some of the main findings highlighted by the authors:
  1. Average actual outturn cost for Summer Games is USD 5.2 billion (2015 level), and USD 3.1 billion for Winter Games
  2. The most expensive Summer Olympic games in history was London 2012, which cost $15 billion. The cheapest one was in Tokyo in 1964, for a grand total of only $280 million.
  3. Olympics have the highest average cost overrun of any type of megaproject, at 156 percent in real terms.
  4. Fourth, and finally, the Rio 2016 Games, at a cost of USD 4.6 billion, appear to be on track to reverse the high expenditures of London 2012 and Sochi 2014 and deliver a Summer Games at the median cost for such Games. The cost overrun for Rio – at 51 percent in real terms, or USD 1.6 billion – is the same as the median cost overrun for other Games since 1999.

By the way, Flyvbjerg has given a interesting interview at EconTalk. Highly recommended.

click on the image to enlarge it