Tuesday, May 22, 2018

Using deep learning and satellite imagery to improve land use classification in cities

Marta Gonzalez and colleagues have a recent paper using deep learning and satellite image data to improve land use classification. The authors have made documented code and Jupyter notebooks available hereI'm self recommitting the paper and code to my future self. HT Marco De Nadai.


Albert, A., Kaur, J., & Gonzalez, M. C. (2017, August). Using convolutional networks and satellite imagery to identify patterns in urban environments at a large scale. In Proceedings of the 23rd ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (pp. 1357-1366). ACM.


Abstact:
Urban planning applications (energy audits, investment, etc.) require an understanding of built infrastructure and its environment, i.e., both low-level, physical features (amount of vegetation, building area and geometry etc.), as well as higher-level concepts such as land use classes (which encode expert understanding of socio-economic end uses). This kind of data is expensive and labor-intensive to obtain, which limits its availability (particularly in developing countries). We analyze patterns in land use in urban neighborhoods using large-scale satellite imagery data (which is available worldwide from third-party providers) and state-of-the-art computer vision techniques based on deep convolutional neural networks. For supervision, given the limited availability of standard benchmarks for remote-sensing data, we obtain ground truth land use class labels carefully sampled from open-source surveys, in particular the Urban Atlas land classification dataset of $20$ land use classes across $~300$ European cities. We use this data to train and compare deep architectures which have recently shown good performance on standard computer vision tasks (image classification and segmentation), including on geospatial data. Furthermore, we show that the deep representations extracted from satellite imagery of urban environments can be used to compare neighborhoods across several cities. We make our dataset available for other machine learning researchers to use for remote-sensing applications.


Tuesday, May 15, 2018

Urban Picture

Nova Iguaçu (Brazil). Nova Iguaçu is a municipality in the Metropolitan Area of Rio de Janeiro. The ocean and some of Rio's mountains can be seen in the background of the picture.



source: vonsenke on reddit, HT Vitor Gabriel

Sunday, May 13, 2018

Against All Authority

Happy mothers day

credit: ?

Tuesday, May 8, 2018

Visualizing space-time networks

I've said this on Twitter before but I should say it here as well. Craig Taylor and the Ito World team have some of the best data visualizations of geospatial data related to cities and transport networks.

Just a few days ago, Craig tweeted some of his latest work with neat visualizations of drive-time network for catchment area analysis. Here is a video comparing different cities in the UK and a brief explanation on how to read the dataviz.
"30 minute drive time analysis from major UK cities visualised as 3d coral geometry. 
The thickness of artery is proportional to the number of networks connected to it indicating busier routes. The falloff in height is linked to the proximity to the centre. 
Corals aren’t normalised in scale as the purpose of this is visualising the form and pattern the networks create. Animation is a boomerang motion scaling from 0 to 30 min and back again. Congestion/traffic not accounted for."

click at the bottom of the video to watch it in full screen and high definition



Yep, there are some obvious parallels here with Time Geography and in particular with the representation of space-time prisms. The static version of the space-time trees gives a sharper visualization of the data.

The space-time tree, or 3d coral geometry as Craig said.

and the inverted original dataviz, "the drive time web"

Thursday, May 3, 2018

Cities in Brazil: A Law and Economics Research Agenda

Just a few days ago, Edward Glaeser presented at the Harvard Law School Brazilian Association Legal Symposium (video below). Glaeser talked about his recent research and some of the questions it raises towards a research agenda on various challenges faced by cities in Brazil but also in other countries from the developing world. This is a self-recommendation post, I haven't watched the full video yet. Hat tip Bruno Bodart.


ps. curious fact mentioned in the video. Glaeser's PhD thesis advisor at Chicago was the Brazilian economist José Scheinkman.


Wednesday, April 25, 2018

When the deadline is close and you need to finish that manuscript

This is how I feel my PhD thesis looks like right now.

image source: reddit

Tuesday, April 24, 2018

Map of the day: how many Switzerlands fit in Brazil


Quite a few, actually. You can  procrastinate  play around with your own map comparisons to  here.




Sunday, April 22, 2018

Mass housing aerial photography in Mexico

“High Density”, a photo essay by Jorge Taboada addressing the proliferation of large and segregated complexes of social housing in Mexico. Hat tip Yuri Gama






Thursday, April 19, 2018

Ex-ante evaluation of the accessibility impacts of transport policy scenarios: equity assessment of BRT expansion

About a month ago, I submitted the 4th paper of my PhD research for publication. The preprint of the paper is available at Open Science Framework (OSF), and you can download it here. Please feel free to read and cite share the manuscript. Suggestions and  criticisms  nice comments are always welcome.

Pereira, R. H. (2018). Ex-ante evaluation of the accessibility impacts of transport policy scenarios: equity and sensitivity to travel time thresholds for Bus Rapid Transit expansion in Rio de Janeiro. OSF Preprints http://doi.org/10.17605/OSF.IO/SUT7R

Abstract:
The accessibility impacts of transport projects ex-post implementation are generally evaluated using cumulative opportunity measures based on a single travel time threshold. Fewer studies have explored how ex-ante accessibility appraisal of transport plans can be used to evaluate policy scenarios and their impacts for different social groups or examined whether the results of project appraisals are sensitive to the time threshold of choice. This paper analyzes how different scenarios of full and partial implementation of the TransBrasil BRT project in Rio de Janeiro (Brazil) will likely impact the number of jobs accessible to the population of different income levels under various travel time thresholds of 30, 60, 90 and 120 minutes. Compared to a partial operation scenario, the full implementation of TransBrasil that extends this corridor into the city center would lead to higher accessibility gains due to network effects of connecting this BRT to other transport modes. Nonetheless, the size of the accessibility impacts of the proposed BRT as well as its distribution across income classes would significantly change depending on the time threshold chosen for the accessibility analysis. Considering cut-off times of 30 or 60 minutes, both scenarios of TransBrasil would lead to higher accessibility impacts in general and particularly for low-income groups, moving Rio towards a more equitable transportation system. However, under longer thresholds of 90 and 120 minutes, an evaluation of this project would find much smaller accessibility gains more evenly distributed by income levels. The paper highlights how time threshold choice in cumulative opportunity measures can have important but overlooked implications for policy evaluation.

Some of the core findings of the paper mentioned in the abstract are illustrated in the figure below. The figure brings box plots that show the distribution of gains in job accessibility via public transport by income groups under partial and full operation scenarios of the TransBrasil BRT project in Rio de Janeiro. The results are shown separately given different choices of travel time thresholds in the accessibility analysis.


Sunday, April 15, 2018

Wednesday, April 11, 2018

Assorted links

  1. Automation and AI will increase spatial/regional inequalities. Paper by Morgan Frank and colleagues

  2. Explore, select and download data of the global population projections by age, sex and education, a great collaborative work of researchers from the Wittgenstein Centre for Demography and Global Human Capital

  3. Greyhound: a powerful platform to interactively explore and analyze massive point clouds with Trillions of points in the browser, via Howard Butler



  4. The dynamical structure of political corruption networks. A paper by Haroldo RibeiroLuis Alves et al., analyzing 27 years of political corruption scandals in Brazil

  5. Citywide effects of high-occupancy vehicle restrictions: Evidence from “three-in-one” in Jakarta, by Rema Hanna et al.

  6. Want to find statistically significant hierarchical modules in weighted networks? paper here and code here, by Tiago Peixoto, who is the author of the graph-tool Python library



Saturday, April 7, 2018

Urban Picture

Petare, Venezuela

credit: via Ricardo Hurtubia‏. I couldn't find who is the author of the photo, though

Monday, March 26, 2018

Transport legacy of mega-events and the redistribution of accessibility to urban destinations

Good news! The 2nd paper of my thesis is coming out of the oven \o/ . The paper has not been assigned to a journal issue yet, but here you go (pdf).

The paper engages with the literature on mega-events and urban development to understand the particularities of transport planning in Rio de Janeiro, conducted for almost two decades under a context of mega-events planning. It is argued in the study that evaluations of the impacts of mega-events on urban infrastructure should take into account the distributional effects of the transport legacies created by those events, looking particularly at how such transport developments reshape social and spatial inequalities in access to opportunities.

This is the first empirical paper of my thesis. Two other empirical papers are currently under review, but you can read their preprints here and hereMy theoretical paper is available herein case you are interested  or have sleeping problems .


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

Abstract:
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.

Saturday, March 24, 2018

Urban Picture

Morro da Providência favela, the first favela in Brazil, reflected on a new corporate building in the old port area of Rio de Janeiro.


Soundtrack:

Thursday, March 22, 2018

8th International Congress Mobility and Transportation, Bogotá

I will be in Bogotá (Colombia) speaking at the 8th International Congress Mobility and Transportation on the first week of April (conference program here). I was kindly invited by TRANSMILENIO S.A, the company that runs the renowned Transmilenio BRT system. The event will gather policy makers, private operators, start ups and academics to discuss some of the main issues and challenges in urban transportation in Latin America.

 To my supervisors, if the ever read this  I know this will be a little distraction from writing by thesis, but it will be a unique opportunity to share my research with experts in the region and to meet some great people. Also, I'm excited that I'll share the floor with Robert Cervero on a panel about the impacts of public transport on cities.

I will be presenting part of my doctoral research, looking at how major transport policies implemented in Rio de Janeiro have impacted people's access to schools and jobs and increased social and spatial inequalities in access to opportunities (preprint of this paper). I will also talk a bit about a new paper where I analyze the TransBrasil BRT project in Rio and estimate its likely future impacts on accessibility inequalities in the city (preprint here). I'll post more info about this paper soon.


Monday, March 19, 2018

"Even wealthy families, good neighborhoods and two parents can’t protect black boys from racism"

The title is this blog post comes from Emily Badger (Twitter), who has written a great piece for the NYT, covering the latest study of Raj Chetty and colleagues. Using a unique dataset, the study shows that black men consistently earn less than white men, regardless of whether they're raised poor or rich. The full paper is here.

The study is part of The Equality of opportunity Project, an ambitious and groundbreaking project led by Chetty. I've posted about the project in this blog a few years ago.


Thursday, March 15, 2018

Using R to Predict Route Preferences in Bike Sharing

Daniel Patterson has written a really great post/tutorial on how to use R to identify what routes are most frequently used by cyclists in the bike sharing program of the Twin Cities area of Minnesota. It's a good and quick read, you should check it out.

Daniel's analysis was conducted using stplanr, an R package for sustainable transport planning. This package was developed by Robin Lovelace, who is a great enthusiast for active transport and one of the most important developers for spatial and transport analysis in R.

credit: Daniel Patterson

Friday, March 9, 2018

Quote of the Day


And damn, I'm good at this!   the making mistakes part, at least 

I saw this quote on via Programming Wisdom, great account to follow on Twitter.

Wednesday, March 7, 2018

Political populism and the revenge of the places that don’t matter

Earlier this year, Andrés Rodríguez-Pose (Twitter) published an interesting article where he points out to a pattern in the relationship between the outcomes of some national elections/referendums and the regional development inequalities in some countries. This is the core of Andrés' argument:
Persistent poverty, economic decay and lack of opportunities cause discontent in declining regions, while policymakers reason that successful agglomeration economies drive economic dynamism, and that regeneration has failed. This column argues that this disconnect has led many of these ‘places that don’t matter’ to revolt in a wave of political populism with strong territorial, rather than social, foundations.

According to Andrés Rodríguez-Pose, this help us understand the rise of populism we have recently witnessed in the national elections/referendums in Thailand, Germany, UK, France, USA and now in Italy. The strength of this apparently simple idea becomes evident when one looks at the spatial distribution of electoral outcomes vis-a-vis the social and economic disparities within those countries.

We have elections in Brazil this year. I’m looking forward to seeing whether the results are going to follow the pattern noted by Andrés. I’m afraid yes, but in a slightly different way. Like in many other countries, Brazil is also seeing the rise of a right-wing conservative populist wave. I believe this wave will be strong in the poorest regions and economically declining cities of the country, following the pattern of the "revenge of the places that don’t matter". However, my hunch is that this wave is going to be particularly strong in the rural areas that are thriving economically, not because of economic reasons but because these areas are traditionally conservative Moreover, I think it is really hard to say what is going to happen in the poor rural areas of the poorest stagnant regions of the country (North and Northeast). In the recent past, these regions have leaned towards the often populist center-left Labor Party, but the political importance of this party has been tremendously shaken in recent years due to corruption scandals and a a contentious impeachment process. If these regions keep their historical support to the Labor Party, this would contradict Andrés' conjecture.

These are only two small particularities that I think will make the Brazilian case diverge a bit from the pattern noted in the conjecture of the "revenge of the places that don’t matter". I might be wrong and I hope I am. In any case, the Brazilian election will be a good opportunity to put this conjecture to test.

image credit: Andrés Rodríguez-Pose

Tuesday, March 6, 2018

Scientific Communication

Quick note to say I've been a bit absent from blogging while I'm writing up  stressing out about  my PhD thesis.  I keep tweeting a bit more often though.


Cartoon by Tom Gauld, HT Arthur Charpentier

Sunday, February 18, 2018

Saturday, February 17, 2018

Urban Picture

Hisashimichi interchange in the city of Hachioji, in Tokyo Metropolitan Area.  You can see this interchange on OpenStreetMap, here. Thanks Pedro Geaquinto for sharing the OSM link!


photo credit: ?

Friday, February 9, 2018

A survey of the literature on mobile phone datasets analysis

A good paper giving a nice overview of the research using mobile phone datasets (mostly CDR data). A lot of interesting research looking at human mobility patterns, spatial and temporal networks, urban and regional development. This paper is already 3 years old, though, and things move fairly quickly in this type of research.

Some of the authors covered in this review are on Twitter. I've tagged them here and here in case you'd like to follow them.

Blondel, V. D., Decuyper, A., & Krings, G. (2015). A survey of results on mobile phone datasets analysis. EPJ Data Science, 4(1), 10.

Abstract:
In this paper, we review some advances made recently in the study of mobile phone datasets. This area of research has emerged a decade ago, with the increasing availability of large-scale anonymized datasets, and has grown into a stand-alone topic. We survey the contributions made so far on the social networks that can be constructed with such data, the study of personal mobility, geographical partitioning, urban planning, and help towards development as well as security and privacy issues.

image credit: Wang et al. 2009

Thursday, February 8, 2018

Waiting for my supervisors' feedback

#truestory



UPDATE: 

More work needs to be done ... of course


Carnival is taken very seriously in Brazil

And now, back to writing.


Wednesday, February 7, 2018

Thoughtful thread on the future of shared, autonomous and electric mobility

For those not familiar with Twitter, click on this link to read the full thread.

On a related note, Tim Schwanen pointed out to this interesting piece about the State led emerging role of China in electric mobility industry.


Wednesday, January 31, 2018

How much residential space could you rent with $1,500 in 30 global cities?

I saw this chart on Twitter via Simon Kuestenmacher.

Infographic: Where Renters Get the Most and Least Space | Statista You will find more statistics at Statista

Related posts:
  1. Comparing house price trends worldwide
  2. The effects of rent control on tenants, landlords, and inequality
  3. Aggregate homeownership rates for different countries
  4. Map of real estate prices in Sao Paulo
  5. Empty spaces in the crowd: Residential vacancy in São Paulo


UPDATE [6 Feb 2018] Apparently, the data is for 2016. The source of the date is a real state intelligence company called Yardi Matrix. They have another version of the chart that includes the 100 most populous cities in the US.

How much residential space could you rent with $1,500 in the 100 most populous US cities?


Tuesday, January 30, 2018

Oxford from above

A beautiful panoramic view of Oxford from above (via BBC Oxford). Apparently you need to go on Facebook to get the interactive version of the picture below.

In case you would like to see how Oxford looks like on the ground, there is actually a camera that streams in real time the day-to-day of Broad Street, one of the main roads in the city. Or, you can explore Oxford on Google Street View and go inside some colleges and libraries

ps warning: Oxford is always NOT always sunny as you see on Google Street View. It rarely is, really.



Sunday, January 28, 2018

The health and economic benefits of cycling network expansion in 167 European cities

A recent study has analyzed the associations between cycling network length and mode share, and estimated the health impacts of the expansion of cycling networks across 167 cities in 11 European countries. According to the study, if all 167 cities assessed achieved a 24.7% bicycle mode share, over 10,000 premature deaths could be avoided annually. The study was led by Natalie Mueller and conducted by a network of European researchers. Thanks Christian Brand for the pointer.

Mueller, N., et al. (2018). Health impact assessment of cycling network expansions in European cities. Preventive medicine. (in press).

Abstract:
We conducted a health impact assessment (HIA) of cycling network expansions in seven European cities. We modeled the association between cycling network length and cycling mode share and estimated health impacts of the expansion of cycling networks. First, we performed a non-linear least square regression to assess the relationship between cycling network length and cycling mode share for 167 European cities. Second, we conducted a quantitative HIA for the seven cities of different scenarios (S) assessing how an expansion of the cycling network [i.e. 10% (S1); 50% (S2); 100% (S3), and all-streets (S4)] would lead to an increase in cycling mode share and estimated mortality impacts thereof. We quantified mortality impacts for changes in physical activity, air pollution and traffic incidents. Third, we conducted a cost–benefit analysis. The cycling network length was associated with a cycling mode share of up to 24.7% in European cities. The all-streets scenario (S4) produced greatest benefits through increases in cycling for London with 1210 premature deaths (95% CI: 447–1972) avoidable annually, followed by Rome (433; 95% CI: 170–695), Barcelona (248; 95% CI: 86–410), Vienna (146; 95% CI: 40–252), Zurich (58; 95% CI: 16–100) and Antwerp (7; 95% CI: 3–11). The largest cost–benefit ratios were found for the 10% increase in cycling networks (S1). If all 167 European cities achieved a cycling mode share of 24.7% over 10,000 premature deaths could be avoided annually. In European cities, expansions of cycling networks were associated with increases in cycling and estimated to provide health and economic benefits.

credit: Mueller et al. (2018)

Friday, January 26, 2018

Amserdam in the 70s

A nice photograph that makes us think how of many cities and their transport systems in the world today look very much similar to how Amsterdam used to be in the 1970s. A bit more on this topic on this previous post:  "We are not Amsterdam".



picture via Old Pics Archive

Thursday, January 25, 2018

A review of 85 Agent-Based Modelling platforms and tools

A recent paper has conducted a comprehensive literature survey comparing 85 Agent-Based Modelling platforms and tools according to the easy of development (simple-moderate-hard) as well as their capabilities (light-weight to extreme-scale). Via Danilo Freire (Twitter)

Abar, S. et al (2017). Agent Based Modelling and Simulation tools: A review of the state-of-art software. Computer Science Review. Volume 24, May 2017, Pages 13-33

Abstract:
The key intent of this work is to present a comprehensive comparative literature survey of the state-of-art in software agent-based computing technology and its incorporation within the modelling and simulation domain. The original contribution of this survey is two-fold: (1) Present a concise characterization of almost the entire spectrum of agent-based modelling and simulation tools, thereby highlighting the salient features, merits, and shortcomings of such multi-faceted application software; this article covers eighty five agent-based toolkits that may assist the system designers and developers with common tasks, such as constructing agent-based models and portraying the real-time simulation outputs in tabular/graphical formats and visual recordings. (2) Provide a usable reference that aids engineers, researchers, learners and academicians in readily selecting an appropriate agent-based modelling and simulation toolkit for designing and developing their system models and prototypes, cognizant of both their expertise and those requirements of their application domain. In a nutshell, a significant synthesis of Agent Based Modelling and Simulation (ABMS) resources has been performed in this review that stimulates further investigation into this topic.

By the way, one of the large-scale models that is relatively easy to use is the UrbanSim model, developed by Paul Waddell's team at Berkeley and which is freely available on GitHub. MATSim scales well with really large simulations and it's also open-source available on GitHub.

click on the image to enlarge it or go read the paper :) 


Tuesday, January 23, 2018

My talk at Transforming Transportation 2018 and personal impressions on TRB


The two conferences have quite different audiences, though, and I had to adapt my presentation accordingly. While TRB is a typical academic conference, TT is more policy oriented and mostly attended by high-level practitioners. So it was a bit of a challenge to tailor the presentation for TT, particularly because I was only given about 8 minutes  and I was super nervous . I had to cut most of the important 'details' of the research methods and findings which I think make the original contribution of the paper.

Here is the result. My talk at Transforming Transportation 2018 was recorded and you can watch it below.



If you have time, I would recommend watching the whole video and check the talk by Joanna Moody (MIT), who is the other Lee Schipper awardee of 2017 and who is conducting a very interesting research on 'car pride' in different countries. The video also brings a bit more context about the Lee Schipper Memorial Scholarship. Applications to the 2018 Lee Schipper award are open, by the way.


Here are a few personal impressions on the TRB conference:
  • The TRB annual meeting is perhaps the largest academic conference on transportation, with approx 15 thousand people. And I thought the annual conference of the American Association of Geographers (AAG) was big with 9k
  • As you can imagine, the most demanded sessions at TRB were on big data, sharing economy and smart cities and all possible combinations of these topics. I am sure there must have been a session on the potentials of big data to inform the mobility sharing economy and create smarter cities
  • There were a few dozens of studies on transportation equity, multimodal accessibility analysis, socio-spatial inequalities and segregation using all sorts of data sources such as GTFS, GPS, mobile phones, social media etc. A lot of work is now being conducted in R as well. Only few studies, though, would do a good job at combing robust methods/data to a more theoretically grounded view of accessibility measures and transportation equity, including a more critical understanding of these issues.

It was a humbling experience to attend TRB and one of the takeaway lessons I took with me is this. 
  1. The academic environment is getting more competitive, with many more good scholars taking advantage of the richer data sources available out there and conducting super interesting research using cutting edge methods and open source software. The frontier is moving quickly.
  2.  Beyond the increasing challenge of getting published, it is getting harder to stand out from the crowd and write studies that will be read/cited for having a real impact within the academic community. It is easier nowadays to write good papers. It is becoming harder, however, to give an original contribution.
  3. The bright side of this story, though, it that on the technical side it is getting relatively easier to use the state of art methods/data from academic research to tackle 'real' problems, improve public policies etc  on the political and governance side things are crazier than ever, though 

Thursday, January 18, 2018

A challenge for your mental model of the world map

Here is a great exercise to test how accurate is your perception of the relative sizes of countries and continents. My score was 67% in my 1st try and 74% in my second try. Not good considering I'm doing a PhD in geography. sssh don't tell my university otherwise they might not give me my degree

This is part of a PhD research at Ghent University. ht Sebastian Meier‏


Wednesday, January 17, 2018

Following the advice of my supervisors

"Sure, it is totally doable", I said...  #truestory


many times #truestory

Friday, January 12, 2018

Data visualization of the day

Scott Kerr‏ on Twitter: "Data visualization of where I cut stuff"

image credit: Scott Kerr‏

Thanks Chico Camargo for the pointer!

Tuesday, January 9, 2018

The effects of rent control on tenants, landlords, and inequality

Good read on the effects of rent control. There are many interesting results and Damon Jones presents a very good summary and discussion in this thread.

Diamond, R., McQuade, T., & Qian, F. (2018). The Effects of Rent Control Expansion on Tenants, Landlords, and Inequality: Evidence from San Francisco. NBER Working Paper No. 24181

Abstract:
We exploit quasi-experimental variation in assignment of rent control to study its impacts on tenants, landlords, and the overall rental market. Leveraging new data tracking individuals’ migration, we find rent control increased renters’ probabilities of staying at their addresses by nearly 20%. Landlords treated by rent control reduced rental housing supply by 15%, causing a 5.1% city-wide rent increase. Using a dynamic, neighborhood choice model, we find rent control offered large benefits to covered tenants. Welfare losses from decreased housing supply could be mitigated if insurance against rent increases were provided as government social insurance, instead of a regulated landlord mandate.

Thursday, January 4, 2018

Sao Paulo from above in new year's eve

This video is from 2016/2017 but there are shorter ones from this year and from 2014 which also give a good idea of how Brazilians take year's eve quite seriously.



Wednesday, January 3, 2018

On my way to Washington DC

I'm flying to DC in the next few days. Thanks to the Lee Schipper Memorial Scholarship I was awarded in 2017, I am going to present part of my doctoral research at both the TRB annual meeting and Transforming Transportation. In both occasions, I will be presenting an in-progress version of the 3rd paper of my thesis, which you can read below. In case you're in DC next week and would like to grab a  coffee or beer, drop me line or a tweet.

Pereira, R. H. M., Banister, D., Schwanen, T., & Wessel, N. (2017). Distributional effects of transport policies on inequalities in access to opportunities in Rio de Janeiro. SocArXiv. doi:10.17605/OSF.IO/CGHX2. Available at https://osf.io/cghx2

Abstract:
The evaluation of the social impacts of transport policies is attracting growing attention in recent years. Yet, this literature is still predominately focused on developed countries. The goal of this research is to investigate how investments in public transport networks can reshape social and geographical inequalities in access to opportunities in a developing country, using the city of Rio de Janeiro (Brazil) as a case study. Recent mega-events, including the 2014 Football World Cup and the 2016 Olympic Games, have triggered substantial investment in the city’s transport system. More recently, though, bus services in Rio have been rationalized and reduced as a response to a fiscal crisis and a drop in passenger demand, giving a unique opportunity to look at the distributional effects this cycle of investment and disinvestment have had on peoples’ access to educational and employment opportunities. Based on a before-and-after comparison of Rio’s public transport network, this study uses a spatial regression model and cluster analysis to estimate how accessibility gains vary across different income groups and areas of the city between April 2014 and March 2017. The results show that recent cuts in service levels have offset the potential benefits of newly added public transport infrastructure in Rio. Average access by public transport to jobs and public high-schools decreased approximately 4% and 6% in the period, respectively. Nonetheless, wealthier areas had on average small but statistically significant higher gains in access to schools and job opportunities than poorer areas. These findings suggest that, contrary to the official discourses of transport legacy, recent transport policies in Rio have exacerbated rather than reduced socio-spatial inequalities in access to opportunities.