What to read on inequality?

A friend asked me: “Which book on inequality should I read? – And I won’t read more than one”. I try to answer:


If you don’t want to read much – he said one book – I think it is even easier than reading an entire big book on inequality. Read a couple of good, concise articles and look at the empirical evidence yourself.

There are 2 big books that currently dominate the discussion on inequality – here is what they are about and what to read instead:


Thomas Piketty’s – Capital in the 21 Century

  • Piketty did a great job of improving our understanding of the long-term trends of inequality – by having the simple but very fruitful idea to rely on tax records to reconstruct inequality data for the time that governments make their citizens pay income taxes. The book also discusses the growth of incomes and crucially the distribution of wealth.
  • What to read instead: Read a good review and look at the data yourself.
    • Branko Milanovic – himself an expert on economic inequality – wrote a early review of Piketty’s book which is also a great summary of the big book: Here it is.
    • The data on top incomes is easily accessible at the World Top Incomes Database – you can also visualize it there! The other data presented by Piketty is available at Quandl here.


Tony Atkinson’s – Inequality – What can be done?

    • Tony Atkinson’s is currently dominating the discussion. He is the world’s foremost scholar of inequality and published on the topic for decades. His latest book has a detailed discussion of how inequality has evolved, but is focusing on what we should do about the high levels of inequality in case we would actually decide to do something.
    • What to read instead:


Personally I think there is too much focus on what has happened at the top of the income distribution. My colleagues at EEG and I are trying to understand what is happening across the entire distribution – and crucially what is happening at the bottom. Similar research is done at the OECD and they just published their third big report on inequality. To go through their work (latest report here) is my final addition to this inequality reading list.

On OurWorldInData you find a series of data visualizations and a list of data sources so that everyone can study what is going.

Debate: Has the world improved in the last 60 years?

At the Oxford Martin School I debated with Anders Sandberg from Oxford’s Future of Humanity Institute and Robert Walker from the University’s Social Policy department whether we achieved to build a better world.

Unfortunately it happens too often that panel discussions don’t lead to much discussion at all because the speakers don’t have much that they disagree on. This discussion was different. We had a long and controversial debate! No shouting and not too much politics, but very different angles from which we tried to answer the question.

Robert focused on poverty and social policy and Anders went back to 1957 and looked at how far we came with computing, genetics, nuclear power, and space travel. And while the topics were quite far from each other they all tied in with the main question: Do we live in a better world?

And if you are interested: Here are all the slides that I used in this presentation for download.

Thanks again to the Martin School, Robert, Anders, and all those who came – especially those that asked many interesting questions – for this event! Hope you enjoy the debate on Youtube!


Presenting at Medicine Conference – Health, Prosperity, and Peace

OurWorldInData.org is an interdisciplinary project and so I was delighted to have the chance to present at a conference for doctors in Austria last weekend. Great to talk to an audience with a different perspective and to learn from them!

At the annual OEADF conference in Salzburg, Austria I was asked to take a long-term perspective on global health, global prosperity, and peace. Here are the slides that I prepared for the 45-min talk:


Download all slides: Global Health, Prosperity, & Peace – OEADF 2015


I tried to find a balance between a global perspective and to focus on some aspects of Austria’s history. It is worth remembering how recently Austria grew out of absolute poverty. This chart is based on Martin Ravallion’s data (published in this World Bank report) and shows how recent the history of poverty in Austria really is.Poverty AustriaIn my talk on Saturday I talked about the history of the so called ‘Swabian children’ (Schwabenkinder): Poor peasant families from the Alps (today’s Austria, Switzerland, and Italy) sent their children to ‘child markets’ in Swabia (Germany). At the markets they were bought or rented for the season to work on the fields. Around 5,000 to 6,000 children crossed the mountain passes to get to Germany – the main pass being at the today glamorous ski resort of St. Anton. Here is the picture (source) of Swabian Children that I showed in my talk. A picture from the Alps – today one of the richest regions in the world – not even hundred years ago.


Have a look at the slides to see it in the context of the presentation!

Combining visualisations and text – What is possible?

As I mentioned yesterday I created OurWorldInData somewhat accidentally when I was doing research for a book on global development that I planned to write. I will still want to write this book. It will visually present the empirical evidence that I am showing on OurWorldInData but I want to add my narrative to this. The website is presenting the facts about the world the book is showing how I put these views together and what we can learn from this.
To achieve this I have to find a way of combing data visualisations with text. I have collected some example to learn from how others have done this. I came across some great work and I hope it can be an inspiration for others to create their own work. Also, I feel that there must be more out there. What am I missing?

Academic Journals – Columns to combine large and small visualizations

Journals often put a huge emphasis on visualizations. In fact publications in Science or Nature are often completely structured around a couple of very good visualizations that present the main finding.

The layout of these journals is mostly structured by 2 or even 3 columns. One advantage of this is that wide visualizations can be combined with smaller visualizations. The screenshot from a recent paper that shows that the global forest area is now increasing shows an example.

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A screenshot of a paper in Nature Climate Change.

This is also this LaTeX template that creates this layout for you.

Tufte Style

Edward Tufte – widely respected as an authority in data visualisations – uses a similar layout in his books. He combines one wide main text column with visualizations that are either as wide as the entire page, or wide as the text column, or are small and fit next to the text. This also allows a combination of different sizes but I’m not convinced there is an advantage over the layout in academic journals.

Tufte photo0
An example of the layout used by Tufte. From: Edward R. Tufte – The Visual Display of Quantitative Information (2001)

There is also a LaTeX template for this and the physicist David McKay uses it for his absolutely fantastic (and free!) book on sustainable energy. So you can see for yourself if this layout convinces you.

Merging text and visuals

Some authors take visuals and make them part of the text flow.

A first example is Oliver Byrne’s classic edition of Euclid (freely available here).

euc-I-5A modern example are Randall Munroe’s cartoons.

Screen Shot 2015-06-01 at 22.47.02

Overlaying visuals with text

This style that is often used in infographics merges text and visuals by using the visual as a canvas on which text is highlighting and explaining some aspects.

thumb_IMG_3931_1024This example is from Sandra Rendgen’s very inspiring Understanding the World: The Atlas of Infographics.

Mixing text with interactivity

I’m pretty tired today because I spent way too much time with “Explorable Explanations” yesterday night..
These online documents allow you to manipulate visualisations which in turn manipulate the text. You have to go and see these if you haven’t. A great example is Brent Victor’s Ten Brighter Ideas, a text where every claim expressed in words is backed up by data that becomes visible on mouseover. He writes: “Digital documents aren’t subject to the constraints of paper. We should hold modern propaganda to a higher standard. By all means, be catchy, eloquent, passionate, and inspiring. But we must be able to dive through the pretty words to see the data and sources beneath.”

He also wrote “Explorable Explanations” with which he coined the term for this genre.

And one more by him: Scientific Communication As Sequential Art where he rewrote a paper on network theory published in Nature made it into an explorable explanation.
A list of many explorable explanations can be found at ExplorableExplanations.com.
Here is an explanation of OLS regression and here is an explorable explanation of how small differences in preferences lead to segregation.


Which beautiful and useful ways of combining text and visuals did you come across? Share it with a comment here.

Short history of OurWorldInData – and where to go from now

Short history: Why I built OurWorldInData.org

About 4 years ago I started working on a book in which I wanted to take a long run perspective and show how the world is changing. There is a need for this since the journalism that informs most of us about how the world is changing is way too focused on current events. Journalists are reporting news – events that happen now – and the long trends that slowly but steadily shape our world are left out of the picture. ‘Industrial revolution happening right now‘ never was a headline.

A consequence of the focus on current events is that many have a very negative picture of how the world is changing – a negative event often happen in an instant (terrorist attack, industrial accident, or natural catastrophe) while most of the very positive events only move very slowly (child mortality or violence are declining over decades or centuries). The idea for the book was to show these long-term trends. I believe we should know these trends and understand what drives them so that we can learn from them and continue to build a better world.

To prepare the book project I started collecting empirical data and visualizations of data on everything that matters for our living conditions. I ended up with a lot of data: Now, after 4 years of data collection this is a database on more than 600 topics (air pollution, terrorism, dental health) and it includes probably around 10,000 visualizations on these topics.

Initially this data collection was just my preparation to write a good book. But when I started working in Oxford it was Tony Atkinson‘s idea that it would be useful to present the empirical evidence I collected freely available for everyone on the web. We came up with the plan to visualize the data and put these visualizations in context – why do these changes matter for us?, what are the limitations of the data?, what is driving these long-term changes? how are the trends interlinked? This is how I ended up building OurWorldInData.org.

For a long time it was my side project that I did in addition to my research on economic inequality. This changed when I told David Hendry about this. He was enthusiastic about it from the start and supported my work on this website. At his research program (EMoD) he gave me the freedom to split my time between research on inequality and the construction of the website. David was immensely helpful: He is one of the world’s top experts on time series econometrics and therefore the very best expert to have on a project that is all about a long run perspective on how things are changing. And he is doing empirical research on a huge range of topics (from the link between productivity and wages (VoxEU here) to research on climate change (together with Felix Pretis) so that he is informed about the many different topics that are covered at OurWorldInData.

It was also together with David that I applied for external funding for OurWorldInData. We applied at the Nuffield Foundation – an institution that is very successfully funding empirical research that is focusing on well-being. The Nuffield Foundation has a great track record of supporting research that matters for the public by getting the work done in research institutions out to a larger public.

Where are we now

The London based Nuffield Foundation gave us a grant to expand OurWorldInData over the course of this year and I’m very thankful for this opportunity. It allows me to devote more time on this project and crucially it means that I’m not doing the work alone anymore: OurWorldInData.org now has a team.

The new team

A month ago I started working with two very talented new colleagues. Lindsay Lee, who is helping to expand the content of the website and Zdenek Hynek, who is building a new framework for storing and presenting the data.

Lindsay is currently doing a MSc in Applied Statistics at Oxford and from September onwards she will continue to do a Master of Public Policy here. She just started working for OurWorldInData – in addition to the preparation for her statistics exams (!) – and she is already doing fantastically useful work for the project. I think she is such great help because she combines very strong quantitative skills  (she is a statistician) with a very good understanding of what the data tell us and why the data matter (she is also a public policy student). Lindsay will continue to work on the project and I’m very much looking forward to continue to work with her. We are planning to add a lot more content together – particular on the empirical evidence of how health is changing around the world.

And did you see the great example of how to combine visuals and text that she chose for the background of her website? She really is a great fit for the project.


Zdenek is a London based developer with very strong skills in the technologies that are used for visualizing data on the web. He knows his JavaScript, d3.js, php, SQL, – but don’t take my word for it, have a look yourself: Here are two past projects of Zdenek that I like a lot:

CzechCrime.org visualizes the data on crime in the Czech Republic. It is a great example for the kind of job where visualization is useful: yes, the data has been available for some time, but it is only now after you build a useful tool that this data can actually tell you something.

ecotrust Canada is an example for Zdenek’s skills to design clean, useful websites. I also like the way that maps are used in this site to highlight the work that the ecotrust is doing.

One of biggest problems of the current technical framework of OurWorldInData is that each visualization has to be done individually: A spreadsheet with the data has to be prepared and then you have to write a page of html and javascript to visualize the data stored in this file. This means a lot of manual work to add one visualization and it is also very cumbersome to update figures with new data.

Zdenek is building a system that will eliminate this tedious, not-scalable process. He is essentially creating two tools: A first tool that allows us to upload data into one central SQL database (as opposed to the current system of individual unconnected csv files). And a second tool with which we can then pull any of the data from this database and visualize it in an interactive chart.

Next week we are planning to use this new system for the first time! Zdenek’s job is absolutely fundamental for the future of this web publication and it has been fantastic to work with him.


This is what is happening here in our office in Oxford – do you have additional ideas for our work? Are you missing anything on OurWorldInData? Do you have ideas or requests for our work? – Please tell us via the commentary section below!