Uncommon chart types: Waffle charts
Uncommon chart types: Waffle charts
If you thought a pie chart was the only food-related chart type out there, think again! There is the donut chart – basically just a pie chart with a hole in the middle – but as a Belgian, I am particularly fond of what’s called a waffle chart. It’s a great alternative to a pie chart, and very easy to make. Oh dear, my stomach’s growling already!
What is a waffle chart?
A waffle chart is basically a square display, usually consisting of 100 smaller squares arranged in a 10-by-10 layout. The squares are colored according to the proportions you are aiming to visualize, similarly to how you would color different slices of a pie chart. As this square layout somewhat resembles a delicious waffle, this immediately explains the name of the chart:
![waffle chart about waffles](https://baryon.be/wp-content/uploads/2020/04/waffle-chart-01-uai-258x215.jpg)
However, compared to a pie chart, a waffle chart is much easier to read – our brain is not well suited to compare different angles and slices, but we can quite easily compare different areas.
Alternative waffle charts
You will notice that many waffle charts are not made up of squares, but of alternative shapes, usually circles. Other shapes, such as small icons, are also possible – in this case we are approaching the realm of pictogram charts.
![economist waffle chart](https://baryon.be/wp-content/uploads/2020/04/economist1-uai-258x161.jpg)
Another alternative are waffle charts consisting of more (or less) than 100 units, where the items represent actual numbers rather than fractions or percentages:
![5g waffle chart](https://baryon.be/wp-content/uploads/2020/04/5g-uai-258x335.jpg)
Here, each square represents $10 million, rather than 1%.
In the latter case, there are some similarities with charts we typically see after elections, showing the distribution of the different seats. One could argue that these kind of charts (‘Parliament charts’) are just a form of ‘warped’ waffle charts:
![parliament chart](https://baryon.be/wp-content/uploads/2020/04/parliament-uai-258x238.jpg)
A Parliament Chart created using Flourish.
Some people prefer to turn their waffle charts by 45°, simply for design purposes, but well, some people are just weird:
![diamond charts](https://baryon.be/wp-content/uploads/2020/04/diamond-uai-258x92.jpg)
Creating waffle charts
Making waffle charts is maybe a little bit tedious, but very simple! For example, you could create square cells in Excel, and color them using intelligent cell formatting to recreate the effect. If you google ‘waffle chart Excel‘ you will immediately get hundreds of blog posts and video tutorials describing the necessary steps.
Or you could take your favourite graphics software (such as Paint.NET, GIMP, or Inkscape), draw 100 identical shapes and color them according to your data.
And some people have managed to do it in Infogram, apparently.
More waffles than you'll ever need
To conclude, some wonderful things people have done with waffle charts, including this tile grid map of waffle charts about internet use in Africa:
![waffle chart on internet usage in Africa](https://baryon.be/wp-content/uploads/2020/04/africa1-uai-258x190.jpg)
Apparently created by one.org, but I can’t find the exact source!
Oh, and a circular waffle chart is sometimes called a plum pudding chart, after J.J. Thomson’s plum pudding model for the atom, which is in turn named after a Christmas cake. The more you know!
![plum pudding chart](https://baryon.be/wp-content/uploads/2020/04/plum-uai-258x158.jpg)
Finally, if you would ever think about creating a 3D waffle chart… it’s not impossible, but let’s say it’s frowned upon. Maybe we should keep that 3rd dimension for real waffles only?
![3d waffle chart](https://baryon.be/wp-content/uploads/2020/04/3d-uai-258x487.jpg)
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This chart is trying to trick you
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We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
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Data visualization in a time of pandemic - #5: On top of the outbreak with daunting dashboards
Data visualization in a time of pandemic - #5: On top of the outbreak with daunting dashboards
This is a multi-chapter post!
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
![Title: data visualization in a time of pandemic](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-02-uai-258x81.jpg)
Chapter 5: On top of the outbreak with daunting dashboards
There’s so much coronavirus data out there – and more is being generated every second. In order to keep the overview, or at least keep some of our sanity, many organizations and individuals have created dashboards. Rather than being a lengthy, descriptive overview, this chapter will point you to some of the best dashboards out there. For those who want to stay on top of things, even during these crazy times.
Dashboards by official organizations
The WHO maintains a Situation Dashboard. This one was recently updated to a much brighter and cleaner design. Make sure to scroll down to see more than just the map! Especially the breakdowns by country are a great addition:
![Country breakdowns for the number of cases on the WHO Situation Dashboard](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-01-uai-258x136.jpg)
Country breakdowns for the number of cases on the WHO Situation Dashboard.
The WHO Regional Office for Europe also maintains a dashboard, albeit of somewhat dubious design quality. Nevertheless, it contains some interesting gauge graphs (created with Infogram) to illustrate how much the most affected countries contribute to the total number of cases in Europe:
![Gauge graphs indicating the contribution of the most affected countries to the total number of cases and deaths (Source: WHO Regional Office for Europe)](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-02-uai-258x85.jpg)
Gauge graphs indicating the contribution of the most affected countries to the total number of cases and deaths (Source: WHO Regional Office for Europe).
The European CDC (Centre for Disease Prevention and Control) has its own dashboard, although in my experience, it is rather difficult to navigate, with a complex layout, a few visual bugs and some counterintuitive (sideways) scrolling which makes it difficult to quickly find the numbers you are looking for.
![These are not the numbers you're looking for](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-03.jpg)
Dashboards by experts
No, we are not talking about the many armchair virologists or epidemiologists popping up on social media or Medium. This is the real stuff: dashboards created by universities, groups of universities, or teams of experts.
Johns Hopkins University – of course, who else – has probably the most well-known dashboard on COVID-19, built in Ember.js. The focal point of this rather gloomy-colored dashboard is a bubble world map with different viewing options including confirmed cases, active cases, incidence rate and case-fatality ratio. The map is somewhat difficult to read for certain heavily affected regions, but can easily be zoomed in on:
![Cumulative confirmed cases in Europe as visualized on the JHU dashboard](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-04-uai-258x161.jpg)
Cumulative confirmed cases in Europe as visualized on the JHU dashboard.
![General overview of the JHU dashboard](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-05-uai-258x109.jpg)
General overview of the JHU dashboard.
The Johns Hopkins dashboard also has a mobile-friendly version.
Other noteworthy expert dashboards include:
- University of Virginia COVID-19 Surveillance Dashboard
- The dashboard by Edward Parker and Quentin Leclerc at the London School of Hygiene & Tropical Medicine which, as a nice bonus, also allows you to visualize past outbreaks of SARS (2003), swine flu (2009) or Ebola (2014).
- The Novel Coronavirus HealthMap by the Open COVID-19 Data Curation Group, an initiative including many famous universities such as the University of Oxford and Harvard Medical School. With even a publication in The Lancet, this will be as expert-y as it gets! Basically a (somewhat difficult to read) bubble map, but with some weird navigation tools for you to play around with:
![Novel Coronavirus Healthmap](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-06-uai-258x178.jpg)
Article-like dashboards
As you probably know by now I’m a sucker for beautiful examples of data journalism. An overview of dashboards would not be complete without mentioning some excellent articles summarizing our information about the outbreak:
- Coronavirus Map: Tracking the Global Outbreak in the New York Times
- Mapping the worldwide spread of the coronavirus in the Washington Post
- Sorry for the patriotism, but I should mention the excellent visuals by the dataviz team at Belgian newspaper De Tijd.
- Coronavirus tracked: the latest figures as the pandemic spreads in the Financial Times. Here, I especially like the bold choice to visualize the spread using small multiples – I don’t usually like this approach, but here I must admit it works really well:
![Financial Times small multiples](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-07-uai-258x221.jpg)
More small multiples! MOAR! (Source: Financial Times)
Other initiatives
And finally, some other noteworthy initiatives:
- The Coronavirus Dashboard by Avi Schiffmann and Jensen. Currently at the top of the Google results if you’re looking for coronavirus dashboards, well done!
- Vinícius Henrique Neves created a dashboard in Microsoft Power BI.
- Bing created their own dashboard, which adds some relevant news items and videos to the mix, as well as some interesting treemaps and strip charts:
![Treemap and strip chart on the Bing COVID-19 dashboard](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch5-08-uai-258x81.jpg)
Treemap and strip chart on the Bing COVID-19 dashboard.
This is a multi-chapter blog post!
Continue reading:
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
For all your comments, suggestions, errors, links and additional information, you can contact me at koen@baryon.be or via Twitter at @koen_vde.
Disclaimer: I am not a medical doctor or a virologist. I am a physicist running my own business (Baryon) focused on information design.
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Not all birthdays are created equal... in fact, for most countries in the north temperate zone, more people are born in summer (May - August) than in winter (October - January). This heatmap allows you to check how popular your birth date is. It shows the number of people in Belgium for each specific birthday.
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This chart is trying to trick you
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We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
![](https://baryon.be/wp-content/uploads/2019/09/email-uai-258x194.png)
Data visualization in a time of pandemic - #4: We need to talk about flattening the curve
Data visualization in a time of pandemic - #4: We need to talk about flattening the curve
This is a multi-chapter post!
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
![Title: data visualization in a time of pandemic](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-02-uai-258x81.jpg)
Chapter 4: We need to talk about flattening the curve
Data visualizations rarely become hugely popular among the general public. But recently, a visual appeared which quickly spread on social media, in newspapers and magazines, and even in press conferences and on television. Hundreds of millions have probably seen it by now. Yes, the Flattening the Curve visual is truly a remarkable success story in the dataviz world. So let’s dive into it!
What curve are we flattening?
Let’s start by looking at a prime example of a ‘flatten the curve’ visual, the one in the COVID-19 #Coronavirus Data Pack at Information is Beautiful, as it combines a simple and clean curve design with a lot of additional information:
![Flattening the curve visual from the Information is Beautiful COVID-19 #Coronavirus Data Pack](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-01-uai-258x258.jpg)
Flattening the curve visual from the Information is Beautiful COVID-19 #Coronavirus Data Pack.
We are looking at how the expected number of daily infections will evolve over time since the date of the first case. As described in chapter 2, the shape of these curves is expected to be more or less Gaussian in nature, with an exponential growth phase at the start of the outbreak and reaching a peak at a certain point in time, typically several weeks since the date of the first case. The crux of the graph is the dotted line – the capacity of our healthcare system. There is only a certain number of patients we can treat simultaneously in an effective way, be it due to a lack of equipment (intensive care beds, ventilators,…) or a lack of personnel.
The color choice is very smart here. Orange is related to the curve we want to avoid: an outbreak without protective measures being taken. In this case the number of daily infections will quickly outpace the capacity of our healthcare system, leading to a high fatality rate because patients cannot all be treated effectively.
Blue indicates the scenario we aim for when protective measures are taken (the protective measures are also listed in the figure above). In this case, the spread of the disease will be slowed down. This implies that the outbreak might take longer to die down, but more importantly, the peak in the number of daily infections will not (or not by much) exceed the capacity of our healthcare system. This enables us to treat all patients as effectively as possible and lower the fatality rate.
In one sentence: we need to take protective measures to flatten the curve.
Many visualizers have come up with their own version of the ‘flatten the curve’ graphic. One of the more popular examples was the following animation by illustrator Toby Morris and microbiologist Siouxsie Wiles for The Spinoff, an online magazine from New Zealand:
![Flattening the curve visual by illustrator Toby Morris and microbiologist Siouxsie Wiles for The SpinoffFlattening the curve visual by illustrator Toby Morris and microbiologist Siouxsie Wiles for The Spinoff](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-02.gif)
Flattening the curve visual by illustrator Toby Morris and microbiologist Siouxsie Wiles for The Spinoff.
Before we dive into the many different variations of this curve, we need to briefly discuss a more technical point: should both graphs have the same area, or not?
When looking at both visuals above, this is not very clear. In the Information is Beautiful version, it might seem that the blue, flat curve has a somewhat smaller surface area compared to the orange version, but it is not very extreme. In the animated version, both appear to have a similar area. In some visuals, the difference is much more extreme, such as in this one by Vox:
![Flattening the curve visual by Vox on March 10, 2020](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-03-uai-258x166.jpg)
Flattening the curve visual by Vox on March 10, 2020.
!['Curve 0': the original Flattening the Curve visual as it appeared in the CDC report 'Community Mitigation Guidelines to Prevent Pandemic Influenza' in 2017](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-04bis-uai-258x171.jpg)
‘Curve 0’: the original Flattening the Curve visual as it appeared in the CDC report ‘Community Mitigation Guidelines to Prevent Pandemic Influenza‘ in 2017.
And what happens after the curve? When strict protective measures, such as a lockdown, are released, will we not simply see a ‘restart’ of the outbreak as people start having more social contacts again? In that case, we will have only delayed the outbreak (at a very high economic – and possibliy psychological – cost) and still end up with millions of deaths. Not really, as we will have gained one unbelievably major advantage: time. Time to do more research, bring us closer to effective drugs or even a vaccine, time to build up capacity, time to educate the public.
Tomas Pueyo describes this very convincingly in his article ‘The Hammer and the Dance‘, so I will not go into further detail here. Just one word of advice: proceed with caution. Tomas Pueyo is a great and convincing writer, but he is not a doctor or microbiologist. He is an engineer, ex-consultant and entrepreneur (hmm, that sounds familiar to my own story). He is also the guy who wrote an entire book about the amazing Star Wars Ring Theory without even crediting Mike Klimo, the person who originally came up with it. That’s a pretty douche move, Tomas. But hey, let’s get back to visualizing data, shall we?
![Key visual from Tomas Pueyo's article 'The Hammer and the Dance' on how to use protective measures to fight the epidemic](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-04-uai-258x138.jpg)
Key visual from Tomas Pueyo’s article ‘The Hammer and the Dance‘ on how to use protective measures to fight the epidemic.
When flattening the curve got out of hand
This is one of those rare times in history when a data visualization goes, well, viral (ugh!). I can hardly come up with data visuals which have reached the same level of fame as Flattening the Curve. It has popped up in press conferences, in newspapers and on television in nearly every country on earth. Millions of people have seen it. That’s quite an achievement!
If we try to trace this visual back to its origins, probably the first time it appeared in the media was in The Economist at the end of February, recreated from the CDC original by visual-data journalist Rosamund Pearce:
![Probably the first appearance of the Flattening the Curve visual in the media. (The Economist)](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-05-uai-258x197.jpg)
Probably the first appearance of the Flattening the Curve visual in the media. (The Economist)
![Drew Harris tweet](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-06-uai-258x272.jpg)
Thanks for sharing your wisdom, Drew. (Source)
The New York Times explains it very well in this article.
By now, Flattening the Curve adaptations have exploded. Maybe we should start talking about flattening the curve of Flattening the Curve visuals? (Not my joke, sorry, credits go to Andy Kirk.)
![Flatten the curve Google Image Search](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-07-uai-258x99.jpg)
Ok, maybe this is getting just a tiny bit out of hand. (Source: Google Image Search)
![Rob Dubbin curve meme](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-08-uai-258x193.jpg)
Source: Rob Dubbin
Curve alternatives
Ah, the curve. It just works so well in educating the people! It convinces us in a single glance why staying at home serves the greater good. Never before was chilling in my couch such a great way to save millions of lives, right?
Nevertheless, there are some great curve alternatives (alcurvatives?) to the by now overused visual. The one I must highlight comes from (again, these guys are simply great visualizers) the Washington Post. I like it so much that maybe ‘One Visuals to Rule Them All’ is a more appropriate way to describe it. Rather than showing the same old curves, Harry Stevens decided to simulate the effects of protective measures and social distancing, and show the impact through a series of animations. This is the pandemic spreading with an enforced quarantine, which is starting to ‘leak’:
![Animated simulation of a disease outbreak with quarantine enforced](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-09bis.gif)
Animated simulation of a disease outbreak with quarantine enforced. (Source: Washington Post)
![Simulation results showing the differences between different suppression strategies on the number of sick (brown), healthy (blue) and recovered (pink) people](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-10-uai-258x191.jpg)
Simulation results showing the differences between different suppression strategies on the number of sick (brown), healthy (blue) and recovered (pink) people. (Washington Post)
It quickly became Washington Post’s most popular story ever.
To wrap up this chapter on curves, there is one final visual I would like to share with you. Don’t worry, it’s an alternative to the Flattening the Curve overload, so no curves this time. In fact, it’s another animated illustration by Toby Morris for The Spinoff, the same guy we started our chapter with. It shows how only one person avoiding contact with others can have a dramatic impact on the total number of infections:
![Animated illustration by Siouxsie Wiles and Toby Morris, showing the impact of social distancing on the spread of an infection](https://baryon.be/wp-content/uploads/2020/04/blog-post-ch4-11.gif)
Animated illustration by Siouxsie Wiles and Toby Morris, showing the impact of social distancing on the spread of an infection. (Source: The Spinoff)
I love it.
This is a multi-chapter blog post!
Continue reading:
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
For all your comments, suggestions, errors, links and additional information, you can contact me at koen@baryon.be or via Twitter at @koen_vde.
Disclaimer: I am not a medical doctor or a virologist. I am a physicist running my own business (Baryon) focused on information design.
Read more:
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Our information designer Sofia made this insightful infographic, giving you an overview of eight amazing facts about the brain!
29 September 2022
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Not all birthdays are created equal... in fact, for most countries in the north temperate zone, more people are born in summer (May - August) than in winter (October - January). This heatmap allows you to check how popular your birth date is. It shows the number of people in Belgium for each specific birthday.
19 July 2022
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This chart is trying to trick you
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3 June 2022
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18 April 2022
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When you're teaching data analysis or data visualization, or when you're learning new data visualization tools and techniques, you might be looking for datasets to practice with. Here are some great starting points.
19 October 2021
We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
![](https://baryon.be/wp-content/uploads/2019/09/email-uai-258x194.png)
Data visualization in a time of pandemic - #3: Mapping the virus
Data visualization in a time of pandemic - #3: Mapping the virus
This is a multi-chapter post!
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
![Title: data visualization in a time of pandemic](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-02-uai-258x81.jpg)
Chapter 3: Mapping the virus
A pandemic has a strong geographical factor attached to it, so obviously we are drawn to using maps to visualize how the virus is spreading. Both data visualizers and their audience simply love maps, and I personally do to. As a child, my (geographical, historical, biological, even biblical) atlases where my favourite books and I could browse through them for days. However, pretty as they may be, maps have their own pitfalls and caveats. So be prepared!
![mapping the virus](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-1-uai-258x145.jpg)
Beauty in times of despair
Let’s start with some of the most well-designed examples of maps I have encountered during my research for this chapter. The absolute winner, in my opinion, are these clean but very effective maps by the Washington Post:
![Map showing the global spread of the coronavirus on March 27, 2020 (Washington Post).](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-2-uai-258x145.jpg)
Map showing the global spread of the coronavirus on March 27, 2020 (Washington Post).
To further clarify things, these maps are complemented by a simple table detailing the exact number of confirmed infections or deaths. This gives the reader the choice to look at the broader picture, dive into the detailed numbers, or both.
![Table showing the global spread of the coronavirus on March 27, 2020 (Washington Post)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-3-uai-258x272.jpg)
Table showing the global spread of the coronavirus on March 27, 2020 (Washington Post).
It should be noted that the BBC uses very similar, equally beautiful maps. These are examples of proportional symbol maps, or what most normal people simply call bubble maps. But why exactly do these bubble maps work so well?
Mapping issues
![xkcd cartoon 1138](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-4-uai-258x275.jpg)
![Countries and territories with confirmed cases on March 10, 2020 (ABC News)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-6-uai-258x159.jpg)
Countries and territories with confirmed cases on March 10, 2020 (ABC News).
Although somewhat helpful, such a map may say more about how connected a country is to the rest of the world, rather than showing how the virus has spread. In any case, it does not provide information about the number of cases. From this map on March 10, we cannot deduct that there was only one confirmed case in Burkina Faso, but over 10.000 in Italy, and over 80.000 in China.
A typical approach to avoid this issue are choropleth maps, a complicated name for something very simple. Blame the Greeks, choros means ‘region’ and plethos means ‘multitude’, hence the name. My scientific brain always tricks me into saying ‘chloropleth maps’, probably because it thinks about chloroplasts in plant cells. But don’t get your hopes up, there’s no connection at all — just my stupid brain. The ‘chloro-’ in chloroplasts also comes from Greek, but from chloros, ‘green’. The same origin, it turns out, as chlorine (because of its pale green color) or chloroform (which contains chlorine). But my apologies, I digress… I might have been reading too much Stephen Fry lately, who would probably love this kind of etymological exploratory ramblings.
So, a choropleth map. In such a map, regions are again colored, but the value of the color (lightness or darkness) depends on the underlying parameter, for example the number of infections in a country. In its most basic form it looks like this example by CNBC:
![Choropleth map of reported coronavirus cases worldwide as of March 17, 2020 (CNBC)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-7-uai-258x158.jpg)
Choropleth map of reported coronavirus cases worldwide as of March 17, 2020 (CNBC).
![Choropleth map of the spread of the coronavirus in China as of January 26, 2020 (CNN)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-8-uai-258x194.jpg)
Choropleth map of the spread of the coronavirus in China as of January 26, 2020 (CNN).
However, choropleth maps have their own unfortunate downsides and pitfalls. I will not go into much detail here, as everything was already written down excellently by ‘cartonerd’ Kenneth Field. Let me just summarize:
- choose your colors or color scheme responsibly,
- choose your categories responsibly, and
- use relative numbers to avoid population density distortion.
Or, just maybe, a bar chart might be a better choice:
![coronavirus china bar chart](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-9-uai-258x184.jpg)
🎵 The map isn’t the best way to show your data, so the bar chart is where I go. (Source: Kenneth Field)
![Choropleth map of the total confirmed COVID-19 cases as of March 26, 2020 (Our World in Data)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-10-uai-258x187.jpg)
Choropleth map of the total confirmed COVID-19 cases as of March 26, 2020 (Our World in Data)
Bubble maps, such as the ones by the Washington Post shown above, avoid this trap because each nation gets its own bubble, independent of area, population, or population density. This is what makes this kind of chart so successful to map a wide range of values in a wide range of countries around the globe.
There is only one minor downside: bubbles can start overlapping each other when two neighbouring regions have very large values (or one of them has a large value while the other only a small one). Then your bubble chart might start looking like this:
![Bubble map on the nCoV-2019 Data Working Group dashboard](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-11bis-uai-258x140.jpg)
Bubble map on the nCoV-2019 Data Working Group dashboard.
![Bubble chart showing confirmed coronavirus cases throughout Europe as of March 27, 2020 (Washington Post)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-11-uai-258x215.jpg)
Bubble chart showing confirmed coronavirus cases throughout Europe as of March 27, 2020 (Washington Post)
The return of the table
I already hinted earlier that in some cases, a simple bar chart might be a better option than a complicated map. As Leonardo Da Vinci said: “Simplicity is the ultimate sophistication” (except that he never said that). Another simple but effective alternative might just be… a table.
Many great examples can be found, including the Washington Post ones at the beginning of this chapter, but I was particularly charmed by the Datawrapper ones by Lisa Charlotte Rost, with a clever use of color to bring a touch of optimism to this heavy subject matter:
![Datawrapper tables by Lisa Charlotte Rost (screenshot: March 18, 2020)](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-12-uai-258x283.jpg)
Datawrapper tables by Lisa Charlotte Rost (screenshot: March 18, 2020).
![Table comparing the number of infections and deaths between the Netherlands and Italy](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-13-uai-258x211.jpg)
Table comparing the number of infections and deaths between the Netherlands and Italy.
![Table coronavirus netherlands](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-14-uai-258x295.jpg)
Same data (well, more or less), different story.
Also, differences in age distribution among the population have an impact on the death rate, so it’s rarely a good idea to blindly start comparing different columns or rows with each other, without thinking things through. Remember: if creating panic is your goal, you will always find some data somewhere presented in such a way that you can do so.
There are many, mány more amazing things you can do with tables, also in coronavirus times, but that will be something for another chapter!
Nightmare maps
![staircase from hell](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-14bis-uai-258x157.jpg)
![another horrible coronavirus map](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-14tris-uai-258x173.jpg)
BBC, by the way, has written an interesting story on an old map showing air travel routes going viral (pun not intended) and causing panic because of poor journalism, such as this badly chosen tweet by the Sun:
![the sun misleading tweet](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-15-uai-258x241.jpg)
Journalism: you’re doing it wrong.
Finally, if you would ever think about using a pie chart as an alternative to a map… just don’t:
![horrible coronavirus pie chart](https://baryon.be/wp-content/uploads/2020/03/blog-post-ch3-16-uai-258x187.jpg)
I like pies — Pecan pie! Frangipane pie! Key lime pie! — but not this kind, thanks. (Source: European Scientist)
This is a multi-chapter blog post!
Continue reading:
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
For all your comments, suggestions, errors, links and additional information, you can contact me at koen@baryon.be or via Twitter at @koen_vde.
Disclaimer: I am not a medical doctor or a virologist. I am a physicist running my own business (Baryon) focused on information design.
Read more:
Infographic: Amazing facts about the brain
Did you know that our brain makes up 2% of our body weight, but consumers about 20% of our energy? Did you know that we have a second brain, located in our gut?
Our information designer Sofia made this insightful infographic, giving you an overview of eight amazing facts about the brain!
29 September 2022
How common is your birthday?
Not all birthdays are created equal... in fact, for most countries in the north temperate zone, more people are born in summer (May - August) than in winter (October - January). This heatmap allows you to check how popular your birth date is. It shows the number of people in Belgium for each specific birthday.
19 July 2022
Visualizing Complexity: Dataviz book review
Visualizing Complexity is a great new data visualization book published by information design Superdot. Here's our verdict.
8 July 2022
This chart is trying to trick you
The original chart in this example is trying to suggest a strong correlation between sugar intake and obesity in the US between 1980 and 2000. It does so by carefully choosing the vertical axis ranges and scaling so both lines nicely fall on top of each other.
3 June 2022
Research visuals: all the resources you’ll ever need!
If you want to start creating clear and attractive visuals about your research, but don't know where to start, this page is for you! Here's a complete overview of tools, resources and inspiration you can use as a starting point for your designs.
18 April 2022
Small datasets to practice your data visualization skills
When you're teaching data analysis or data visualization, or when you're learning new data visualization tools and techniques, you might be looking for datasets to practice with. Here are some great starting points.
19 October 2021
We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
![](https://baryon.be/wp-content/uploads/2019/09/email-uai-258x194.png)
Data visualization in a time of pandemic - #2: Visualizing exponential growth
Data visualization in a time of pandemic - #2: Visualizing exponential growth
This is a multi-chapter post!
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
![Title: data visualization in a time of pandemic](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-02-uai-258x81.jpg)
Chapter 2: Visualizing exponential growth
Let me warn you in advance: this will probably be the most theoretical and mathematical chapter of this entire blog post. We’ll have a short look at the underlying scientific principles of a pandemic and analyze how this translates to visualizing data. If that’s not really your thing, it’s totally okay to just look at the pictures and then skip to the next chapter! 😉
![Graph with pencil and paper](https://baryon.be/wp-content/uploads/2020/03/isaac-smith-AT77Q0Njnt0-unsplash-scaled-uai-258x172.jpg)
A mathematical approach to pandemics
A pandemic disease is a complex thing to model. We live in a world of nearly 8 billion people in over 230 countries, connected with each other through 100.000 daily plane flights and an equally mind-boggling number of train and bus rides. Nevertheless, many experts have attempted to model the spread of a disease in a closely-connected world.
For example, professor biostatistics Kurt Barbé models the pandemic spread through a first order differential equation, resulting in the number of active infections following a Gaussian curve, with its typical bell shaped profile:
![Pandemic model by Kurt Barbé](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-03-uai-258x145.jpg)
Different scenarios for the coronavirus spread in Belgium, as modeled by professor Kurt Barbé (March 18, 2020).
This is a simplified but not unrealistic model. For example, if we look at the number of active COVID-19 cases in China, where the peak has nearly passed, we can see that the Gaussian profile is a pretty good approximation (the sudden increase in the number of cases on February 13 is the result of a change in reporting methodology).
![COVID-19 peak in China](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-04-uai-258x161.jpg)
Evolution of the number of active SARS-CoV-2 infections in China.
We can assume that if the number of active infections follows a Gaussian-shaped profile, the number of new infections and the number of deaths will also follow Gaussian profiles. If we plot cumulative data, such as the total number of confirmed cases or the total number of deaths, this will follow an S-shaped cumulative function profile — the integral of the Gaussian function. For example, the total number of deaths by COVID-19 in China looks like this:
![Evolution of the total number of COVID-19-related deaths in China](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-05-uai-258x161.jpg)
Evolution of the total number of COVID-19-related deaths in China.
Crucially, at the start of such peaks and S-curves, the shape will follow an approximately exponential profile, with the number of infections or the number of deaths doubling every few days at a constant acceleration. That’s the reason why we are seeing so many graphs appearing which show the number of infections on a logarithmic scale — such as the one below by John Burn-Murdoch for the Financial Times. On such a log-scale, exponential growth will appear as straight lines. The steeper the line, the more rapidly the growth is accelerating.
![Financial Times graphic by John Burn-Murdoch on the growth of the number of coronavirus cases in different countriesFinancial Times graphic by John Burn-Murdoch on the growth of the number of coronavirus cases in different countries](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-FT-uai-258x166.jpg)
Financial Times graphic by John Burn-Murdoch on the growth of the number of coronavirus cases in different countries.
Which brings us to the following point of discussion: is using a logarithmic scale a good idea?
Logarithmic scales: yes or no?
Using logarithmic scales in a data visualization is sometimes frowned upon, as it has some obvious drawbacks:
- Requires additional explanation when communicating towards a general public, which might not be familiar with this type of plot.
- Not a good way at all to compare values with each other.
However, there are specific cases where the use of logarithmic scales might be justified: when the underlying mechanism behind the data is multiplicative in nature, leading to (more or less) exponential growth. This is exactly the case in the early outbreak stage of a contagious disease (when only a minor fraction of the population is infected).
For example, a patient infected with smallpox will infect on average 5 other people. This is the basic reproduction number of the infection. These 5 people will — on average — each infect 5 new people, or 25 in total. These 25 will infect 5 x 25 = 125, and so on, and so on. For the novel coronavirus, early estimates of the basic reproduction number range between 1.4 and 3.9, which is higher than a seasonal flu (0.9–2.1), but much lower than for example measles (12–18).
The basic reproduction number is influenced by many different factors which cannot be controled, such as the incubation time and the infectiousness of the disease. However, it also depends on the number of susceptible people that affected patients are in contact with. This is the main reasoning behind social distancing measures to ‘flatten the curve’ (more about flattening the curve visuals in a later chapter): the lower the number of people an infected patient comes in contact with, the lower the reproduction number and the slower the disease will spread through the population.
As many countries are currently in the early exponential growth phase of the epidemic, and taking measures to reduce the reproduction number, this is an appropriate opportunity to plot the number of infections (and the number of deaths) on a logarithmic scale. It enables us to quickly evaluate in which countries measures are more effective and the disease is spreading less rapidly, such as Japan or Singapore:
![Number of confirmed coronavirus cases per country, on a linear-logarithmic scale](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-07-uai-258x161.jpg)
Number of confirmed coronavirus cases per country, on a linear-logarithmic scale.
![Basic reproduction number of well-known infectious diseases](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-06-uai-258x258.jpg)
Basic reproduction number of well-known infectious diseases. (Source: Wikipedia)
As an additional benefit, linear-logarithmic plots like these can educate the general public about the exponential nature of the disease in its early stage. This avoids more sensation-oriented headlines such as ‘More new infections today than ever before!’. While this is true, it doesn’t have to mean things are getting out of control. Everything might be entirely as expected, or even improving. As Hans Rosling notes in his bestseller Factfulness (if you haven’t read it, do it immediately!): things can be both better and bad.
A final note on logarithmic scales before I shut up about it and we can move on to more exciting things. As the infection continuous to spread, a growing fraction of the population will become either already infected, or immune when they have been infected in the past but survived. Also, vaccines can be developed, or increasingly strict measures of social distancing and quarantine can be enforced. In practice, this means the effective reproduction number will drop, the exponential growth will start to decelerate and the number of infections will reach a peak and start dropping again. When this happens, the usefulness of logarithmic scales has reached its end.
![Bill Gates quote](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-Bill-Gates-quote-uai-258x286.jpg)
Even Bill agrees.
But aren't absolute numbers meaningless?
By now, I have created many different visuals related to the novel coronavirus, and one of the most pervasive comments concerns the use of absolute numbers. Many people argue that we cannot directly compare numbers between countries without correcting for the population count. This sounds relatively convincing — how on earth can we compare the number of deaths between a tiny country such as Belgium, and a massive nation like China?
However, this is a multifaceted question without a definitive answer. Let me list the major arguments for both approaches:
We must use relative numbers, because:
- The number of infections and deaths in a country depends on the size of that country.
- We want to evaluate the stress the pandemic will put on a country’s healthcare system, which can usually only support a certain fraction of the population being infected.
We must use absolute numbers, because:
- The rate at which a disease spreads depends on the population density and the level of social distancing, but has nothing to do with the population number. In this regard, country borders are pretty arbitrary ways of grouping people, anyway.
- Relative numbers will create pretty meaningless ‘outliers’ for some very small countries.
- Should we plot the relative or the absolute number of infections?
In my impression, most data visualizers follow the approach of using absolute numbers when plotting the total number of infections. The above-mentioned John Burn-Murdoch also agrees:
![John Burn-Murdoch quote](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-JBM-uai-258x202.jpg)
Thanks for backing me up here, John!
Nevertheless, using relative numbers can be very useful for other use cases such as:
- Showing the number of tests performed per capita.
- Showing the available number of doctors, hospital beds, intensive care beds,… per capita.
- Comparing how hard different countries are currently hit by the crisis.
For example, comparing the number of COVID-19 tests performed by country in absolute and relative numbers reveals some interesting insights:
Nevertheless, using relative numbers can be very useful for other use cases such as:
- Showing the number of tests performed per capita.
- Showing the available number of doctors, hospital beds, intensive care beds,… per capita.
- Comparing how hard different countries are currently hit by the crisis.
For example, comparing the number of COVID-19 tests performed by country in absolute and relative numbers reveals some interesting insights:
![Number of tests performed per country and per 1.000 inhabitants](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-08-uai-258x161.jpg)
Number of tests performed per country and per 1.000 inhabitants. (Source: Our World in Data)
This is a multi-chapter blog post!
Continue reading:
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
For all your comments, suggestions, errors, links and additional information, you can contact me at koen@baryon.be or via Twitter at @koen_vde.
Disclaimer: I am not a medical doctor or a virologist. I am a physicist running my own business (Baryon) focused on information design.
Read more:
Infographic: Amazing facts about the brain
Did you know that our brain makes up 2% of our body weight, but consumers about 20% of our energy? Did you know that we have a second brain, located in our gut?
Our information designer Sofia made this insightful infographic, giving you an overview of eight amazing facts about the brain!
29 September 2022
How common is your birthday?
Not all birthdays are created equal... in fact, for most countries in the north temperate zone, more people are born in summer (May - August) than in winter (October - January). This heatmap allows you to check how popular your birth date is. It shows the number of people in Belgium for each specific birthday.
19 July 2022
Visualizing Complexity: Dataviz book review
Visualizing Complexity is a great new data visualization book published by information design Superdot. Here's our verdict.
8 July 2022
This chart is trying to trick you
The original chart in this example is trying to suggest a strong correlation between sugar intake and obesity in the US between 1980 and 2000. It does so by carefully choosing the vertical axis ranges and scaling so both lines nicely fall on top of each other.
3 June 2022
Research visuals: all the resources you’ll ever need!
If you want to start creating clear and attractive visuals about your research, but don't know where to start, this page is for you! Here's a complete overview of tools, resources and inspiration you can use as a starting point for your designs.
18 April 2022
Small datasets to practice your data visualization skills
When you're teaching data analysis or data visualization, or when you're learning new data visualization tools and techniques, you might be looking for datasets to practice with. Here are some great starting points.
19 October 2021
We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
![](https://baryon.be/wp-content/uploads/2019/09/email-uai-258x194.png)
Data visualization in a time of pandemic - #1: Finding reliable data
Data visualization in a time of pandemic - #1: Finding reliable data
Oh no! Not another coronavirus post! Yes, I know, we are bombarded by pandemic content these days. My apologies for creating even more. However, it is not my purpose to bore you with more of the same, or to confuse you with pointless details. Being a passionate information designer I decided to have a look at good and bad practices in COVID-19 related content from a data visualization point of view. I hope this will be a useful and inspiring overview.
This is a multi-chapter post!
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
We are living in remarkable times. The novel coronavirus is causing an epidemic spreading with a velocity we have never experienced before. Busy long-distance air and rail traffic have made it impossible to contain the virus after its first outbreak in China. For the first time our modern world is confronted with a pandemic of this scale and magnitude, and our healthcare systems are being put to the test.
But in fighting these challenges, the world has never been as united as today. Research teams across the globe are working together to develop cures, social media are used extensively to keep everyone informed, and innovative companies are coming up with solutions to keep people at home and the virus at bay. Technology plays a crucial role in this fight.
As an information designer, I am specifically fascinated by the efforts of the data science and visualization communities. The newest developments in these fields are put to use to turn a complex and rapidly changing topic into easy-to-communicate visuals. In only a matter of days, nearly everyone is familiar with the ‘flatten the curve’ visuals, or Washington Post’s animations on the impact of social distancing.
In this post, we will explore some of the marvelous ways people around the world are using data visualization in the fight against the novel coronavirus.
![Title: data visualization in a time of pandemic](https://baryon.be/wp-content/uploads/2020/03/blog-post-visuals-02-uai-258x81.jpg)
Chapter 1: Finding reliable data
As noted by Edward Tufte, excellent graphics consist of complex ideas communicated with clarity, precision, and efficiency. At the core of a good data visual, therefore, lies accurate data. So before we start diving into coronavirus graphs, we will first take a brief stop at trustworthy data sources.
Sources of reliable data
There are currently three important places where one can obtain reliable and relatively complete aggregate data about the Coronavirus epidemic:
- World Health Organization
The World Health Organization publishes daily Situation reports detailing the number of confirmed cases and deaths per country. They also provide a Situation dashboard which is updated three times per day.
![WHO Coronavirus Situation dashboard](https://baryon.be/wp-content/uploads/2020/03/blog-post-1-dashboard-WHO-uai-258x127.jpg)
WHO Novel Coronavirus Situation Dashboard
- John Hopkins University
Researchers at John Hopkins University also maintain a dashboard providing an overview of the current number of cases, deaths and recoveries on a per country basis. The underlying data is made freely available through GitHub.
![John Hopkins University coronavirus dashboard](https://baryon.be/wp-content/uploads/2020/03/blog-post-1-dashboard-JHU-uai-258x110.jpg)
John Hopkins University Coronavirus Dashboard
- European Center for Disease Control and Prevention
The ECDC publishes daily statistics on the pandemic for the entire country (despite its name!). Data is published daily at 1 p.m. CET and is presented on a situation update page.
- Our World in Data
The team of Max Roser collects and combines all available data and information about the epidemic on a single page. This excellent summary provides interactive charts on many different topics ranging from the number of cases to symptoms, incubation period and fatality rate. Each chart comes with a downloadable data set.
Accuracy of data
Collecting and aggregating global data in a rapidly changing environment, such as during a pandemic, is obviously very tricky. None of the above datasets should therefore be considered an ‘absolute truth’, as minor errors are bound to happen. Such errors can be related to reporting difficulties or contradicting sources, or differences and shifts in methodology, but can also be due to minor errors such as typos.
As an example, let us compare the three datasets above for the total number of confirmed cases in Belgium (between March 1 and March 19) with the official numbers communicated by the Belgian government (which can be found here).
![Table of confirmed coronavirus cases in Belgium, by different sources](https://baryon.be/wp-content/uploads/2020/03/blog-post-1-table-Belgium-uai-258x247.jpg)
Comparison between different data sources of the reported total number of confirmed COVID-19 cases in Belgium between March 1 and March 19, 2020.
Immediately we can note some discrepancies. The John Hopkins University data follows the government data most closely, with an exception on March 12 where for some reason the number was not updated.
The two other datasets (WHO and Our World in Data) appear to lag behind by one day up until March 16, possibly because WHO Situation reports are published at specific timings which don’t match accurately with government reporting timings. Also, these datasets miss the same update as the John Hopkins numbers (from 314 to 399 cases), they were not updated on March 17, and they appear to have a typing error in them (1.085 cases on March 16, while the official government number was 1.058).
Finally, Our World in Data temporarily stopped updating beyond March 17 because WHO shifted their reporting window: up until Situation report 57 the observed 24-hour time window ended at 10 a.m. CET, since then it ends at midnight. This causes a small overlap making it difficult to accurately compare data and analyze trends.
- Update March 23: Note that Our World in Data stopped relying on WHO data as they found too many errors in the daily Situation reports. Instead, they switched to data provided by the ECDC.
In summary, John Hopkins University data most closely matches official government numbers (for Belgium).
![Graph of the total number of confirmed coronavirus cases in Belgium in March, from different sources](https://baryon.be/wp-content/uploads/2020/03/blog-post-1-graph-Belgium-uai-258x161.jpg)
Total number of confirmed COVID-19 cases in Belgium in March 2020, comparison between different sources.
Finding more data sources
If you are looking for alternative data sources, direct reports by governments, or data on specific regions or cities, I highly recommend the data section of the Coronavirus Tech Handbook, a crowdsourced document bringing together all the tools, datasets and visualizations on this topic.
The sheer amount of available data can make it a bit overwhelming, especially taking into account that new numbers are being announced almost constantly. When in doubt, I would advise to stick to the four most complete data sources listed above.
This is a multi-chapter blog post!
Continue reading:
- Chapter 1: Finding reliable data
- Chapter 2: Visualizing exponential growth
- Chapter 3: Mapping the virus
- Chapter 4: We need to talk about flattening the curve
- Chapter 5: On top of the outbreak with daunting dashboards
- Chapter 6: Viral scrollytelling
For all your comments, suggestions, errors, links and additional information, you can contact me at koen@baryon.be or via Twitter at @koen_vde.
Disclaimer: I am not a medical doctor or a virologist. I am a physicist running my own business (Baryon) focused on information design.
Read more:
Infographic: Amazing facts about the brain
Did you know that our brain makes up 2% of our body weight, but consumers about 20% of our energy? Did you know that we have a second brain, located in our gut?
Our information designer Sofia made this insightful infographic, giving you an overview of eight amazing facts about the brain!
29 September 2022
How common is your birthday?
Not all birthdays are created equal... in fact, for most countries in the north temperate zone, more people are born in summer (May - August) than in winter (October - January). This heatmap allows you to check how popular your birth date is. It shows the number of people in Belgium for each specific birthday.
19 July 2022
Visualizing Complexity: Dataviz book review
Visualizing Complexity is a great new data visualization book published by information design Superdot. Here's our verdict.
8 July 2022
This chart is trying to trick you
The original chart in this example is trying to suggest a strong correlation between sugar intake and obesity in the US between 1980 and 2000. It does so by carefully choosing the vertical axis ranges and scaling so both lines nicely fall on top of each other.
3 June 2022
Research visuals: all the resources you’ll ever need!
If you want to start creating clear and attractive visuals about your research, but don't know where to start, this page is for you! Here's a complete overview of tools, resources and inspiration you can use as a starting point for your designs.
18 April 2022
Small datasets to practice your data visualization skills
When you're teaching data analysis or data visualization, or when you're learning new data visualization tools and techniques, you might be looking for datasets to practice with. Here are some great starting points.
19 October 2021
We are really into visual communication!
Every now and then we send out a newsletter with latest work, handpicked inspirational infographics, must-read blog posts, upcoming dates for workshops and presentations, and links to useful tools and tips. Leave your email address here and we’ll add you to our mailing list of awesome people!
![](https://baryon.be/wp-content/uploads/2019/09/email-uai-258x194.png)
Improving your graph: a case study
Improving your graph: a case-study
Here’s the thing I love most about visual communication: there’s always room for improvement. As soon as you think a graph or data visualization is finished and perfect, someone else will come along with an idea to make it even better. Take, for example, the excellent series of blogposts “The little of visualization design” by (the amazing) Andy Kirk. How a minor detail can make a visualization so much more awesome!
If you have 15 minutes of spare time, I strongly encourage you to watch the following video, because it’s the perfect example of improving visualizations for dummies, and a great intro for this blog post: https://www.youtube.com/watch?v=IB7crD_paKQ
Summary: Alan Smith, Data Visualization Editor at the Financial Times, shows some great examples of converting ‘meh’ graphs from press releases to awesome visualizations that really tell a story. He also organizes crash courses to teach his fellow journalists how to do this in order to become more ‘data critical’.
In this blogpost, I’d like to do the same for a graph I encountered in my Twitter timeline a few days ago. To come straight to the point, here’s the graph we’ll redesign:
![Lelijke grafiek](https://baryon.be/wp-content/uploads/2019/11/0-V1uFkYMUEOEOS4lJ1-uai-258x153.png)
The graph is taken from a (publicly available) research paper on predicting depression from Instagram pictures. In short, the filter you use to prettify your Instagram pictures tells something about how you feel. Okay, to be more precise, there appears to be a correlation between the usage of certain filters and the mental health state of an Instagram user. You can see that in the graph above, but it’s not very clear. Let’s improve that!
Step 1: Readability
I’ve always learned that horizontal words are easier to read than vertical words. So, let’s turn all those words 90° to improve readability. In fact, why not rotate the entire graph? There’s no real added value in the current orientation.
![graph v1](https://baryon.be/wp-content/uploads/2019/11/0-uUzjBewvUPTVcDky-uai-258x406.png)
Hey, this just saved us from some serious neck injuries!
![Examples of different instagram filters](https://baryon.be/wp-content/uploads/2019/11/0-4mM3G9YwwopZqT_x1-uai-258x258.png)
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