On February 20th, an outbreak of Corona virus began in Italy. It is believed to begin from the region Lombardy. Since then, the number of cases began growing exponentially in northern Italy. As part of European Union, Italy shares a “seamless” border, both by land and by flight, with other European country, including France and Germany. This put the neighboring country into test, whether they can contain the contagion of the virus.
I’m a student living in Toulouse, France. As part of the curriculum, I have to do an internship at the end of my study. Interested in drone, I choose Japan as the country where I will spend 6 months as an intern, starting from the 6th of April. I plan to leave France at the end of March since I have a project presentation on the 26th. However, the Corona virus cases began to spread wildly in France, after the Outbreak in Italy. This occasion put me into uncertainties, will it be fine, for my case, to stay in France until end of March?
If France has a major spike for the Corona virus, I might have to be quarantined when I arrive in another country outside France. The quarantine period may last up to 14 days. Taking this consideration, if I leave France on the 27th of March and take a flight directly to Japan, I won’t be able to start my internship in time. It will be delayed up to the next Monday, 13th of April. Clearly, I should leave as soon as possible, I will apply the visa in Indonesia. But, when should I leave?
I asked my research project supervisor regarding the situation. Amid the outbreak, it will be hard to stay until end of month. I proposed him to have the final presentation online and he agreed. I am thinking of meeting him once more before I leave, so I booked a flight to Indonesia for Tuesday, March 17th.
However, things are not going well. I heard from a friend that India will quarantine anyone coming from Europe, starting from Friday, March 13th. Trump also announced that US imposes a travel ban from the continents. I also read news that Indonesia banned any flight from and to Italy, when the cases hit 9000.
I have to make a calculation, like, literally!
My calculation should give me number when any flight from France, or Europe, will be banned by Indonesian government, assuming they will do the same restriction as for Italy. I take the number of Covid-19 cases from a website, they provide number of total cases as well as new cases, every day. I made a logarithmic regression taking the number of cases as the input and predict the number of cases on 17th of March. It gives me the result as shown below!
The result is startling! By 17th of March, there will be more than 20 thousand cases in France. However, something does not feel right. The new cases count is about 500 on March 11th but on March 12th it will be 1800. The next day, March 13th, an addition of 1600 new cases will happen. The jump from 500 to 1800 is a wild estimation and decrement to 1600 on the next day does not make sense. Something must be wrong with the model, even the correlation (R2) is high.
I recall the comment section on 3Blue1Brown video, someone mentioned that the “number of cases” does not grow exponentially. It is the “number of new cases” that follows this trend. Therefore, I did remodel considering exponential growth of the “number of new cases” and find the result as follows.
The regression result seems reasonable, there’s no unreasonable spike between day to day. Taking this for my flight planning, I have to change reschedule it! March 17th is too late to go back to Indonesia. The latest will be this Saturday, March 14th, as Indonesian government will probably take more prudent consideration, banning the flight when the number hits 5 thousand. Another remark is there is only one direct flight from Europe to Indonesia. If the other countries impose a travel ban, it might be harder to reach Indonesia.
Soon after this calculation, I reschedule my flight for Saturday afternoon. Unfortunately, a night before the flight, the airline canceled all flight for European country. Soon after hearing the news, I booked another flight to Indonesia using Singapore Airline. Gladly, Singapore imposes travel ban starting from 23.59 on March 15th. I can have my flight to Indonesia and apply my visa to Japan when I arrived.
Had I waited for March 17th to go back to Indonesia, the return trip to would be extremely difficult as only limited flights served and the French government has put the country into lock down. Thanks to data driven decision making, I could go back to Indonesia in a less complicated situation.
Moral of the story: in hard times, whenever you want to make a decision, use data! It gives you an estimate of the future, much better than assuming.
Fazlur Rahman 