Wednesday, December 19, 2018

The transport legacy of Mega-Events in Rio favored the richest and was offset by an economic crisis

self-promotion alert 

My PhD research was covered on BBC Brazil today. They present a very good summary (in Portuguese) of some of the main results. If you have insomnia problems  are interested in reading the full thesis, it is available for download here.

image credit: Fernando Frazão/Agência Brasil

Sunday, December 16, 2018

3D interactive map of population densities across the globe

A couple of years ago, I wrote a blog post showing where to find data on population estimates at high spatial resolution for the world. These are great sources of data if one wants to explore and visualize how population density varies across the globe, like in this neat interactive map created by Duncan Smith (CASA UCL).

I'm a big enthusiast of 3D density maps, as you might have noticed by so many of these posted on the blog before (such as this 1, this 2, this 3, this 4, this 5, ....). And apparently I'm not alone. A few days ago, Matt Daniels created a beautiful 3D interactive map of population densities and it went viral on the internet. You can procrastinate browse around the map and check your own region, but don't miss the story Matt published at The Pudding.

image credit: Matt Daniels (The Pudding)

Monday, December 10, 2018

Open position for a research assistant in the Access to Opportunities Project at Ipea, Brazil

This post will probably be of interest to only a small share of readers living in Brazil.

We have an open position for a research assistant to work with me in the Access to Opportunities Project at the Institute for Applied Economic Research (Ipea). The aim of the project is to estimate accessibility to employment opportunities as well as education and health services in the largest urban areas in Brazil. The project focuses on how social and spatial inequalities in access to opportunities relate to urban transportation, housing and land use policies. We are estimating accessibility by public transport, walking and cycling at a high spatial resolution for all of the Brazilian major cities, what will generate a massive amount of data each year. My plan is to make the data outputs and results publicly available to policy makers and researchers, with whom we will be able to collaborate in the future to analzye particular case studies in Brazil but also to conduct comparative studies involving cities in Brazil and other countries.

The research assistant will be based in Brasilia (Brazil) and we are looking for someone with advanced skills in R. Applications will be open until the 20th of January 2019. More details can be found here (info in Portuguese only). Please, help spread us the word.

Thursday, December 6, 2018

Chart of the Day and a Biographical note

I was given this birthday card by my partner yesterday. Isn't she lovely?! This is a great chart  and bit too honest .

I also received yesterday an email I wrote myself five years ago. There is this website FutureMe, which allows you to send an email to your future self. You just have to write a message, point to a destination email address and the date when the email will be received. The email I received yesterday was written right after I had moved to Oxford. It was written by a younger Rafa who was thrilled to start a PhD but also insecure if he belonged to that place, and someone who had lots of questions about how my life would unfold in the following years. I'm glad about the answers I have today for the questions I had back then.

I write these emails to my future self once every two or three years. I find it a great exercise to reflect about life and to keep track of how my thoughts, ideas, fears, plans etc change over time. You should give it a try,

ps. FutureMe is a free website and they didn't pay me to write this post.

Tuesday, December 4, 2018

Apply for the 2019 Lee Schipper Memorial Scholarship for Sustainable Transport and Energy Efficiency

Since 2012, WRI Ross Center for Sustainable Cities awards a young researcher every year with the 
Lee Schipper Memorial Scholarship for Sustainable Transport and Energy Efficiency. This award was created to celebrate Lee Schipper, one of the founders of EMBARQ and an enthusiastic supporter of building closer links between rigorous research and policy-making. The Scholarship awards up to two candidates a maximum of $10,000 each to advance transformative research in efficient and sustainable transport. Applications are due by January 25, 2019.

I was honored along with Joanna Moody to receive this award in 2017, what allowed me to organize a seminar to discuss my research with policy makers, practitioners, civil society and academics and to write a much stronger piece of research during my PhD and present it at two major conferences. It was a great and enriching experience and I would strongly encourage other researchers to apply for the Lee Schipper Award.

Monday, December 3, 2018

Assorted Links on mortality

  1. The case for monitoring life-span inequality, via José Manuel Aburto

  2. Mortality from road crashes in 193 countries: a comparison with other leading causes of death, ht Romulo Krafta

  3. The slowing pace of life expectancy gains since 1950

  4. How life expectancy in U.S. counties compares to other countries via Simon Kuestenmacher

  5. R package: mortAAR, for archeological demography. It provides functions for the analysis of archaeological mortality data See Chamberlain (2006). There is a vignette on Lifetables and an Extended Discussion

  6. R package: MortalityLaws, for downloading data from the Human Mortality Database and building parametric mortality models and life tables, by Marius Pascariu

  7. R package: MortCast, for estimating and Projecting of age-specific mortality rates, by Hana Sevcikova, Nan Li and Patrick Gerland (paper here) - via Adrian Raftery‏

  8. Beautiful Lexis-surface plot showing age and period specific mortality ratios of females and males, by Jonas Schöley (interactive version at the Human Mortality Explorer)

image credit: Jonas Schöley

Saturday, December 1, 2018

Thursday, November 29, 2018

Visualizing transport mode share using a ternary colour scheme

This is also a great technique to visualize how transport mode share varies across different neighborhoods of a city. This chart below was created by Ignacio Pérez and it shows the mode split of different communes in Santiago (Chile).

image credit: Ignacio Pérez

Wednesday, November 28, 2018

Academic Outreach

While many academics would like to (or are expected to) develop research with impact on the real world outside the ivory tower, this is how the academic publication process often look like. Via SAS.

Tuesday, November 27, 2018

Using GIFs to explain what various causal inference methods

Nick Huntington-Klein (CSU Fullerton) has created a series of excellent gifs to illustrate what various causal inference methods do to data and how they work. The whole thread on Twitter is worthwhile, specially because learning these econometric methods becomes much easier once we have a solid understanding of the concepts and intuitions behind them. (Thanks Bernardo Furtado for the tip).

obs. Nick created these gifs in R using the gganimate package and the code is available here.

Here's the gif that shows the intuition behind difference-in-differences

Wednesday, November 21, 2018

Widening roads to reduce congestion is like loosening the belt to tackle obesity

A gentle reminder that widening roads to reduce congestion is like loosening the belt to tackle obesity *

Related links:

* UPDATE: Apparently, this metaphor was originally used by the urban planner Lewis Mumford in 1955. “Building more roads to prevent congestion is like a fat man loosening his belt to prevent obesity”.

Thursday, November 15, 2018

The landscape and pulses of dockless bikes in Singapore

Yang Xu ‏(Twitter) and his team at the Hong Kong Polytechnic University have a new research project to understand the usage of dockless bike-sharing system and its relationship with built environment in Singapore. More info about the project in Yang's website.

Nice kickoff video created using

Wednesday, November 14, 2018

PhD thesis officially deposited and available for download

PhD thesis officially deposited! You can download the thesis here and check the R code I used in the data wrangling, mapping and analysis in this GitHub repo.*

ps. Special thanks to my friend Christine Moore for making the deposit.

* If you find any mistakes, let me know and I'll try to find someone to blame for.

Tuesday, November 6, 2018

The top cities by scientific output in 2018

The group Nature has updated the Nature Index and published a special issue raking cities and metro areas by their scientific output. There is a vast literature on cities as engines of growth and creativity because of economies of agglomeration, proximity and face-to-face contacts, social and cultural diversity etc. It's interesting to see how scientific outputs are clustered around major urban areas in the world.

The method they used to define urban clusters, however, is not entirely clear.  It seems a bit odd to me that they put Columbia, Princeton and Yale Universities in the same 'New York' cluster given the distance and commuting ties between these urban areas. My guess is that based on the same criteria, London-Oxford-Cambride (UK) should also be considered as a single cluster but they are treated separately. The same would happen with Sao Paulo-Campinas-Sao Jose dos Campos (Brazil).

In any case, the report brings plenty food for thought, including this brief analysis showing that the top collaborating cities are located in the same country.

Sunday, November 4, 2018

Future access to essential services in a growing smart city

Warning of  shameless  self-promotion:

I'm glad to share that some colleagues at UBC (JeromeMartino and Nuttall) and I have a new paper published. In this paper we analyze how projected population change could affect future accessibility demand to education and healthcare services and transportation equity, looking at the case of Surrey in Canada. One thing in particular I like about this paper is that it looks at how transport accessibility is affected by changes in population growth and spatial distribution while most studies in the literature have traditionally looked at how accessibility levels change due to modifications in the transport network or in the spatial allocation of schools, healthcare facilities etc. The paper will remain open access for the next 50 days. Download it here or send me an email and I'll be glad to share it to you. 

Mayaud, J. R., Tran, M., Pereira, R. H. M., & Nuttall, R. (2018). Future access to essential services in a growing smart city: The case of Surrey, British Columbia. Computers, Environment and Urban Systems. doi:10.1016/j.compenvurbsys.2018.07.005

The concept of accessibility – the ease with which people can reach places or opportunities –lies at the heart of what makes cities livable, workable and sustainable. As urban populations shift over time, predicting the changes to accessibility demand for certain services becomes crucial for responsible and ‘smart’ urban planning and infrastructure investment. In this study, we investigate how projected population change could affect accessibility to essential services in the City of Surrey, one of the fastest growing cities in Canada. Our objectives are two-fold: first, to quantify the additional pressure that Surrey's growing population will have on existing facilities; second, to investigate how changes in the spatial distribution of different age and income groups will impact accessibility equity across the city. We evaluated accessibility levels to healthcare facilities and schools across Surrey's multimodal transport network using origin-destination matrices, and combined this information with high-resolution longitudinal census data. Paying close attention to two vulnerable population groups – children and youth (0–19 years of age) and seniors (65+ years of age) – we analyzed shifts in accessibility demand from 2016 to 2022. The results show that population growth both within and outside the catchments of existing facilities will have varying implications for future accessibility demand in different areas of the city. By 2022, the city's hospitals and walk-in clinics will be accessible to ~9000 and ~124,000 more people (respectively) within a predefined threshold of 30 min by public transport. Schools will also face increased demand, as ~8000 additional children/youth in 2022 will move to areas with access to at least half of the city's schools. Conversely, over 27,000 more people – almost half of them seniors – will not be able to access a hospital in under 30 min by 2022. Since low-income and senior residents moving into poorly connected areas tend to be more reliant on public transport, accessibility equity may decline in some rural communities. Our study highlights how open-source data and code can be leveraged to conduct in-depth analysis of accessibility demand across a city, which is key for ensuring inclusive and ‘smart’ urban investment strategies.

Monday, October 15, 2018

On the road

This blog and my Twitter will be less active in the next few days.

I'm on my way to California to have a few weeks off from work and celebrate. My partner completed her masters degree and I finished my PhD, so that's a good enough reason for us to celebrate. See you next month. 

ps. If you really have nothing else better to read in the meantime, have a look at this wonderful  PhD thesis.

image credit: ?, via @CityDescriber (funny bot by Geoff Boing)

Tuesday, October 9, 2018

Chart of the Day

A 'very good' (exclamation mark) chart that "reveals exactly how positively and negatively the population perceives various descriptions to be." (ht Simon Kuestenmacher). This chart was created by Matthew Smith, and it was inspired in this older chart below on Perceptions of Probability and Numbers, by Zoni Nation.

Friday, October 5, 2018

How Democracies Die

Here is a great seminar by Steven Levitsky talking about his recent book on how democracies die. I cannot emphasize enough the importance of his message in times of strong political polarization like these.

ps. I know. Politics is not really the focus of this blog. However, the coming Brazilian elections (this weekend) are quite depressing and I've found this video very helpful to make sense of the mess we're in. Spoiler alert: the video will not cheer you up.

Thanks Daniel Cardinali for recommending me the video.

Thursday, October 4, 2018

Urban Picture

Organic Kampala, via BlackZinjah

Monday, October 1, 2018

How complete is OpenStreetMap data coverage?

Mikel Maron (MapBox) has addressed this question in 2015 using the CIA World Factbook as a reference. The coverage varies from country to country, as expected, but it's pretty good overall and it only gets better with time. You can check the results for your country here.

More recently, Barrington-Leigh and Millard-Ball addressed the same questions with different methods (ht Ralph Straumann). The authors arrived at a similar conclusion but they also draw some other interesting findings (see the abstract below).  Obs. I'm curious to know why Bolivia stands out from Latin America.

Barrington-Leigh, C., & Millard-Ball, A. (2017). The world’s user-generated road map is more than 80% complete. PloS one, 12(8), e0180698.
OpenStreetMap, a crowdsourced geographic database, provides the only global-level, openly licensed source of geospatial road data, and the only national-level source in many countries. However, researchers, policy makers, and citizens who want to make use of OpenStreetMap (OSM) have little information about whether it can be relied upon in a particular geographic setting. In this paper, we use two complementary, independent methods to assess the completeness of OSM road data in each country in the world. First, we undertake a visual assessment of OSM data against satellite imagery, which provides the input for estimates based on a multilevel regression and poststratification model. Second, we fit sigmoid curves to the cumulative length of contributions, and use them to estimate the saturation level for each country. Both techniques may have more general use for assessing the development and saturation of crowd-sourced data. Our results show that in many places, researchers and policymakers can rely on the completeness of OSM, or will soon be able to do so. We find (i) that globally, OSM is ∼83% complete, and more than 40% of countries—including several in the developing world—have a fully mapped street network; (ii) that well-governed countries with good Internet access tend to be more complete, and that completeness has a U-shaped relationship with population density—both sparsely populated areas and dense cities are the best mapped; and (iii) that existing global datasets used by the World Bank undercount roads by more than 30%.

Completeness of the OSM dataset, by grid cell, January 2016.

credit: Barrington-Leigh & Millard-Ball (2017)

Sunday, September 30, 2018

Quote of the Day - social science

“We live in an era of social science, and have become accustomed to understanding the social world in terms of 'forces,' 'pressures', 'processes', and 'developments'. It is easy to forget that those 'forces' are statistical summaries of the deeds of millions of men and women who act on their beliefs in pursuit of their desires. The habit of submerging the individual into abstractions can lead not only to bad science (it’s not as if the 'social forces' obeyed Newton’s laws) but to dehumanization" (Steven Pinker)

Sunday, September 23, 2018

The day I became a Doctor

I'm very glad  and relieved  to share the news that I became a doctor last week! It might take some time for the university to publish my PhD thesis, so I've decided to make the preprint of the thesis available for download here. I've also created a GitHub repository to share the R code used in the data wrangling, mapping and analysis in the thesis.

My examiners were Nihan Akyelken and Bert van Wee. They were super kind but very challenging, nonetheless. In the end, the PhD viva lasted for 2.5 hours and I was super nervous the whole time. I really enjoyed the viva, though, and I was so surprised when they said I had passed with no corrections that I almost jumped out of my chair. I got this result largely because of my incredibly  demanding  tireless supervisors Tim Schwanen and David Banister, to whom I'm extremely grateful.  All in all, I'm feeling incredibly happy and thankful for the whole journey and the support I received along the away from my family, friends and supervisors. It’s been a truly wonderful and humbling experience.

ps. I still have two papers of the thesis currently under review, but finishing the PhD means that now I'll have much more time to  procrastinate  work on new projects and some others that were put on hold.

photos by my lovely wife, Fabiana - also known as my third supervisor :)

Friday, September 14, 2018

Biographical note: back to the library

Working from the Oxford Bodleian Library and the Radcliffe Camera these days. Getting ready to my PhD defence and the seminar at UCL next week. The blog has been less active these days but I hope to post some good news in the coming days.

Home again

Monday, September 10, 2018

Saturday, September 8, 2018

Presenting a seminar at UCL on Sept 17th: Distributive Justice and Transportation Equity: Inequality in accessibility in Rio

Hi all. I will be in the UK over the next couple of weeks. My PhD defence is on Sept 18th  but I'm too nervous to talk about it these days . Wish me luck !

For those around London, I'll be presenting part of my doctoral research at UCL on Sept 17th (details below). This is part of a new seminar series on Transport and Social Equity jointly organized by the UCL research networks on socially just transport and planning. Thanks Beatriz Mella and Robin Hickman for the kind invitation.

[click on the image to enlarge it]

Thursday, September 6, 2018

Assorted Links

  1. Tokyo has a great public transport system....all things considered

  2. report: Migration Data using Social Media: a European Perspective by Zagheni et al

  3. imagineRio, a searchable atlas that illustrates the social and urban evolution of Rio de Janeiro over the entire history of the city

  4. self recommending: Machine Learning beyond Curve Fitting: An Intro to Causal Inference and do-Calculus, by Ferenc Huszár

  5. Brazil’s National Museum have been lost to fire

  6. The late Waldo Tobler's legendary, seminal, (but unpublished) PhD thesis from 1961 is actually downloadable online. HT Michiel  Meeteren

  7. When should you show percentage changes on a log or linear scale? Great post by Lisa Rost. I should re-read this post every now and then.

  8. Google has launched a search tool for datasets. This is only a beta version but the idea could be really useful in the next years

  9. Calculating driving isochrones considering traffic levels in QGIS (Python script here), by David. If you are more like an ArcGIS person, Riccardo has you covered. BTW, David and Ricardo run the great blog Digital Geography which is also on Twitter.

traffic enhanced isochrones during a in Birmingham
credit: davidribbon

and some isochrones of Chicago

credit: Riccardo

Tuesday, September 4, 2018

Open position at TSU/Oxford for Research Associate in Urban Mobility

This post is just a quick reminder that the Transport Studies Unit (TSU) at Oxford University is recruiting a senior researcher to work on the PEAK Urban project. Ten days left to apply. Job Details here.

This is a really exciting project working with Tim Schwanen (Twitter) in an extremely supportive environment with great colleagues in an excellent research center. I would jump at this opportunity if I could.

Friday, August 31, 2018

New paper out: Transport legacy of mega-events and the redistribution of accessibility to urban destinations

I'm glad to share that the 2nd paper of my thesis is now published. It will remain open access for the next 50 days. Downloaded it here.

This is the 1st empirical paper of my doctoral research. Two other empirical papers are currently under review, but you can read their preprints here and here. My theoretical paper is available here, in case you are looking to have some fun over the weekend.

Pereira, R. H. M. (2018). Transport legacy of mega-events and the redistribution of accessibility to urban destinations. Cities, 81, 45–60. doi:10.1016/j.cities.2018.03.013

Local governments increasingly justify the hosting of mega-events because of their legacy value, assuming that all local residents benefit from those events. Yet, little attention has been paid to the distributive question of who benefits from the transport legacy left by those events. This paper reflects on the delimitation of transport legacies and its social impacts in terms of how such developments can reshape urban accessibility to opportunities. It analyses the transformation in the transport system of Rio de Janeiro (Brazil) in preparation for the 2014 World Cup and the 2016 Olympic Games. That transformation involved substantial expansion in public transport infrastructure, followed by cuts in service levels and a reorganization of many bus lines to streamline the transport system. The paper examines whether those recent changes have increased the number of people from different income levels who could access Olympic sports venues and healthcare facilities by public transport within 15, 30, 60 and 90 min. The analysis uses a before-and-after comparison of Rio's transport network (2014–2017) and a quasi-counterfactual scenario to separate the effects of newly added infrastructure from the reorganization and cuts of transport services. The results show that the infrastructure expansion alone would have increased the number of people who could access the Olympic sports venues, but it would have only marginally improved people's access to healthcare facilities. Nonetheless, the findings indicate that the streamlined bus system have offset the benefits of infrastructure investments in a way that particularly penalizes the poor. The analysis of both the implemented changes to the public transport network and the counterfactual scenario show that the accessibility benefits from the recent cycle of investments and disinvestments in Rio generally accrued to middle- and higher-income groups, reinforcing existing patterns of urban inequality.

Thursday, August 30, 2018

This is how the future of urban transportation will look like

This is true. If this prediction turns out to be wrong in 200 years, I will personally stop writing/editing this blog.

cartoon by André Dahmer

ps. As Ian Philips ‏said: "Excellent to see that in the future there's no compulsory helmet rule for cyclists."

Thursday, August 23, 2018

The geography of Manhattan distorted by travel-times

The figure below was created by Stefan Musch from Gradient Metrics (hat tip Jean Legrand). The figure was created using R and ggplot2 based on travel-time estimates from Google Maps API. There is a bit more info about the creation process in this post and perhaps Stefan will share his code at some point.... please? :)

Echoing the comments of others on Twitter.  The figure does a great job illustrating how it is much harder to cross Manhattan from east to west than from north to south. Finally,  it would be great to see how this shape has changed over the last decades using historical travel time estimates.

credit: Stefan Musch (Gradient Metrics)

Sunday, August 19, 2018

The urban landscape of Hong Kong

Johnny Harris (Vox) has filmed a great series of short-videos that helps us understand the urban landscape of Hong Kong. In one of these videos, Johnny talks about how one of the most unaffordable housing markets in the world is driven by government's land-use regulations. The videos also cover the decline of Hong Kong's neon nightscape and even how feng shui shapes the city skyline. There is also a very informative one about the changing relationship between Hong Kong and China. You can check the list of videos below.

Monday, August 13, 2018

Urban Picture

Barcelona at day and night, by the talented Henry Do (ht Architecture)

Saturday, August 11, 2018

Assorted R Packages for Spatial Analysis

  1. RgeoProfile is an R package for carrying out geographic profiling - a technique derived from criminology that uses the spatial locations of linked crimes to infer the home location (or locations) from which the criminal is operating, by Steve LeComber

  2. rayshader is a package for producing hillshaded maps of elevation matrices with raytracing and spherical texture mapping, by Tyler Mogan.

  3. dodgr: fast calculations of pairwise distances on directed graphs in R, by Mark Padgham

  4. rmapshaper: a simple way to simplify shape files, by Andy Teucher

  5. rpostgis: Linking R with a PostGIS Spatial Database, by David Bucklin and Mathieu Basille

  6. osrmr: a wrapper around the OSRM API, a super fast routing engine for OpenStreetMaps, by Adrian Stämpfli-Schmid

  7. stplanr is a package providing various functions and data access for transport research, by Robin Lovelace. This is the core package underneath The Propensity to Cycle Tool

Monday, August 6, 2018

When you lie in your CV but still get the job

HT Daniel P. Sobreira. Image credit: ?

Tuesday, July 31, 2018

PhD Thesis submitted !

After  4 years, 9 months and 18 days  quite some time, I have finally submitted my thesis to the Examination School of Oxford University. The thesis is entitled “Distributive Justice and Transportation Equity: Inequality in accessibility in Rio de Janeiro”. You can read the abstract below.

Thank you Christine Moore , Homero Paltán and Kevin Wheeler for being there for me, literally !

I will soon share the thesis manuscript. For now, here is the abstract:

   Public transport policies play a key role in shaping the social and spatial structure of cities. These policies influence how easily people can access opportunities, including health and educational services and job positions. The accessibility impacts of transport policies thus have important implications for social inequalities and for the promotion of just and inclusive cities. However, in the transportation literature, there is still little theoretically informed understanding of justice and what it means in the context of transport policies. Moreover, few studies have moved beyond descriptive analyses of accessibility inequalities to evaluate how much those inequalities result from transport policies themselves. This is particularly true in cities from the global South, where accessibility and equity have so far remained marginal concerns in the policy realm. 
   This thesis builds on theories of distributive justice and examines how they can guide the evaluation of transport policies and plans. It points to pathways for rigorous assessment of the accessibility impacts of transport policies and it contributes to current discussions on transportation equity. A justice framework is developed to assess the distributional effects of transport policies. This framework is then applied to evaluate recent transport policies developed in Rio de Janeiro (Brazil) in preparation to host sports mega-events, such as the 2014 FIFA World Cup and the 2016 Olympic Games, which included substantial expansion of the rail and Bus Rapid Transit (BRT) infrastructure. This research presents ex-post analyses of the policies implemented between 2014 and 2017 and ex-ante analysis of an as yet unfinished BRT project. It evaluates how the planned transport legacy of those mega-events impacted accessibility to sports venues, healthcare facilities, public schools and job opportunities for different income groups. 
   The results show that there were overall accessibility benefits from the expansion in transport infrastructure between 2014 and 2017, but these were generally offset by the reduction in bus service levels that followed an economic crisis that hit the city after the Olympics. Quasi-counterfactual analysis suggests that, even if the city had not been hit by the economic crisis, recent transport investments related to mega-events would have led to higher accessibility gains for wealthier groups and increased inequalities in access to opportunities. Results suggest that those investments had, or would have had, greater impact on inequalities of access to jobs than in access to schools and healthcare facilities. The evaluation of the future accessibility impacts of the unfinished BRT corridor, nonetheless, indicates that such project could significantly improve access to job opportunities for a large share of Rio’s population, particularly lower-income groups. Spatial analysis techniques show that the magnitude and statistical significance of these results depend on the spatial scale and travel time threshold selected for cumulative opportunity accessibility analysis. These results demonstrate that the ad-hoc methodological choices of accessibility analysis commonly used in the academic and policy literature can change the conclusions of equity assessments of transportation projects.

Monday, July 23, 2018

Mapping the diversity of population ageing across Europe with a ternary colour scheme

Ilya Kashnitsky and Jonas Schöley have recently published this correspondence in The Lancet where they show a very clever way to visualize the spatial heterogeneity of population age structures using choropleth map with ternary colour scheme. The data wrangling was done in R, and the code to replicate get the data and replicate the figure is available on Github.

Needless to say that, if you're interested in demography, R and data, you should be following the work and twitter accounts of Ilya and Jonas.

click on to image to enlarge it

image credit: Ilya Kashnitsky and Jonas Schöley.

Monday, July 16, 2018

Tuk Tuk Uber

While I was in Dar es Salaam a few weeks ago, Manuel Santana drew my attention to these three-wheeler tuk tuks with "Uber" written at the back (photo below). At first, I thought that was just a marketing strategy or perhaps a funny joke. Little did I knew that those tuk tuks are regular service providers registered with Uber. This is quite telling of Uber's flexibility to adapt to the particularities of each local context (for better or worse).

ps. In case you're wondering, we didn't take Tuk Tuk Uber... We wouldn't be able to squeeze four people in a Tuk Tuk after dinner.

photo credit: Manuel Santana