Visualising Covid-19 data

Covid-19 as you will know has gripped the whole world. It has been classified as a pandemic by the WHO. I am no expert on the disease itself and do not have any expertise on policy making, it would be unwise for me to comment on the actions taken by all the different governments from around the world.

My interest in this is very academic and data driven. The numbers which are changing daily are used to chart the progress of the disease as well as study the impact of the various measures taken to counteract the spread of the virus.

Over the past few weeks, a lot of data has been used to produce graphics which can communicate effectively the information pertaining to this pandemic. Of most relevance I think are the number of confirmed cases and the deaths due to coronavirus stratified by country. Most of these graphics have focused on the raw numbers. Although the raw number is useful it nonetheless is incomplete. I think a better measure is to adjust the raw number by the population of the country. This provides a better measure as to how severe the effect of the virus has been on a country.

Keeping that in mind I produced some graphs for population-adjusted confirmed cases and deaths for some select countries. I plan to update these graphs on a regular basis over the coming weeks to understand the spread of this disease. All plots start on 1 February 2020 and end on the latest date for which I have the data. All data has been sourced from the Johns Hopkins University Center for Systems Science and Engineering (JHU CSSE)a.

Further subdividing the population into gender and age subgroups can provide more nuanced information. A good source for such informative graphics and the related analysisb can be found here.


a JHU CSSE Covid-19 Github Data Repository: link
b Max Roser, Hannah Ritchie, Esteban Ortiz-Ospina and Joe Hasell (2020) – “Coronavirus Disease (COVID-19) – Statistics and Research”. Published online at Retrieved from: ‘’ [Online Resource]

Visualising data

Data visualisation is an essential tool for a statistician or for that matter, any individual user of statistics. It is used to visualise the data being analysed before more rigorous analysis techniques are applied. Or, once the analysis is complete, it can be used as a medium of relaying the results. Visual aids are quite powerful in not only communicating information but also teasing out details from the data.

I learnt a lot regarding good graphics from one of my favourite lecturers at ANU. Another great source for understanding the power of graphics was the many books written and published by Edward Tufte. Anyone in the field of data visualisation would have heard of Tufte. His 1983 book, The Visual Display of Quantitative Information, which has now been reprinted so many times has been a most invaluable source for my learning.

A good graphic will portray relevant information and be self-explanatory. If you feel that you need to provide too much explanation for your graphic, then you might need to reconsider the graphic you have chosen. I think that it is always better to have a simple graph. It is tempting to make an elaborate looking graph which may even be complicated to produce but more often than not, fails to communicate the information.

If you are ever thinking of producing a picture to portray information then I suggest you follow Tufte’s principles of graphical excellence and integrity as outlined in his book mentioned above. To begin with, what a graphical display should do:

  1. Show the data.
  2. The viewer should be able to make inference regarding the data.
  3. Avoid distorting the data.
  4. Make comparisons of different pieces of data easy.
  5. Reveal several levels of detail.
  6. Serve a reasonably clear purpose: description, exploration, tabulation, or decoration.
  7. Be closely integrated with the statistical and verbal descriptions of a data set.

Tufte’s Principles of Graphical Excellence

  • Graphical excellence is the well-designed presentation of interesting data—a matter of substance, of statistics, and of design.
  • Graphical excellence consists of complex ideas communicated with clarity, precision and efficiency.
  • Graphical excellence is that which gives to the viewer the greatest number of ideas in the shortest time with the least ink in the smallest space.
  • Graphical excellence is nearly always multivariate.
  • And graphical excellence requires telling the truth.

Principles of Graphical Integrity

  • The representation of numbers as physically measured on the surface of the graphic itself should be directly proportional to the numerical quantities represented.
  • Clear, detailed and thorough labelling should be used to defeat graphical distortion and ambiguity. Write out explanations of the data on the graphic itself. Label important events in the data.
  • Show data variation, not design variation.
  • In time-series displays of money, deflated and standardized units of monetary measurement are nearly always better than nominal units.
  • The number of information-carrying (variable) dimensions depicted should not exceed the number of dimensions in the data.
  • Graphics must not quote data out of context.
  • Be aware of the Lie Factor, which is a ratio: (Size of the effect shown in graphic)/(size of the effect in data)

My teaching philosophy

I have been fortunate in my school and university days to have been blessed with some wonderful teachers who have ignited in me a passion for the subject I now study and teach. They have cultivated and encouraged in me a holistic view of education. For me, a university education is not just about getting a degree but to gain knowledge. It is a place where you have new experiences both in and outside the classroom. You hope to find the niche where you excel and this is where your teachers play a very pivotal role.

A university education, no doubt, plays a crucial role in teaching skills and imparting knowledge in the relevant field. It prepares a person for a future role in the workforce. But this is not the only job a university education plays. It also produces the next generation of scientists, artists, teachers, etc.  Thus as a university lecturer, one has to balance the varied expectations of the many students. I aim towards being a lecturer who at most times can help each kind of student achieve their personal goal and stay committed to my goal of sharing knowledge and learning. With the advancement in technology, it has become easier to gain access to excellent information. Many wrongly feel that access to information is same as learning or gaining that knowledge. One still needs an expert in that field to impart that knowledge in a meaningful and insightful manner. I constantly work and aim towards reaching that goal.

My personal belief is that a student must work towards excellence in their chosen field and not run after material success. Success, I believe, is nothing but a by-product of excellence. Thus the role of a university teacher is to offer an environment where one can work towards that excellence. I teach in an applied field where the easy way is to teach the student a skill without worrying too much about the process behind the skill. An average student is also very happy to learn that skill which will eventually help him/her in the workforce. But without learning the process the skill will only take you up to a certain point and not beyond. I aim to take the extra step necessary, which will not just teach them the skill but appreciate how, why and where it works.

My experience with education in India

I have been blessed with some wonderful teachers over the years. They have ignited in me a passion for the subject I now study and teach. If it were not for these truly inspiring figures in my life I would have a very different life.

Almost anyone who has studied the sciences in India knows that the way sciences are taught in India makes it very difficult to continue your love affair with the subject. Throughout school, the focus is on getting ‘good marks’ so you can get into a ‘good’ university. When you reach the university level you strive to get ‘good’ marks so you can get a good job and so it goes on like that. Somewhere on that journey, you forget why you undertook the journey, ‘to learn something’.

According to me, the purpose of education, whether it is in school or at university, is to gain knowledge. Sadly in India, the assessment does not reflect the learning you have attained. There is at most times a great disconnect what you learn and what you are tested on. My schools were not much different but along the way I found some teachers to guide my learning which made me the person I am today.

I would not comment on how it is worldwide but the current state of Indian education is that it stymies true learning. There is rigour in our education system and it does produce some great minds but unfortunately, it does not produce many original thinkers. Many would argue that some of the most successful people, in sciences, arts or business are Indians. And they would be correct. But if you look more deeply you will see that most have completed their further education outside India and many have not even had formal education.

Eventually, in learning varied subjects you find your passion and you continue in that field to attain mastery. It can be that you are passionate about engineering, medicine, theatre or music. As long as you are passionate about something, you can put your heart and soul into it and attain great heights.

I feel a major reason for this is that we do not have many original and inspiring educators. Unfortunately, you do not come across too many teachers who inspire the young minds and enhance their potential. I was fortunate in that instant. I got some wonderful teachers along the way. They taught me to how to think originally and critically about my subject.

I also had some wonderful parents who did not want me to take up a specific career because it would be the ‘right’ thing to do. They allowed me to study mathematics in university knowing full well that it was not a traditional field of study one chose in India. In conventional wisdom, these subjects do not lead to what is called ‘successful’ careers. But if I can echo one of the characters from a popular Indian film,

Do not chase success, as you will fail. But if you chase excellence then success will follow you.

I came here to the Australian National University to further my learning in Statistics and Actuarial Studies. I also teach the same subject in my department. I am still learning to be a better teacher every day but my goal is to be as inspiring as my teachers.

I try to instil the same passion I have for my subject in my teaching style.

I know that as long as I am not excited about the subject I teach, my students will never get excited about it.