"The greatest shortcoming of the human race is our inability to understand the exponential function."I became aware this past week that I too have this shortcoming, along with too many others, especially some political leaders and Australian university management.
The graph below is the number of cases of COVID-19 outside China versus time, as of yesterday.
It is taken from the latest WHO report.
According to Neil Howe
N = R0 ^ (T/S)
where N is the infected number, R0 is the average number of persons infected by each infected person, S is the average number of days from infection to transmission, and T (the variable) is days. Most studies of COVID-19 suggest that its R0 is about 2.3 and that its S is about 6 days. As expected, that generates an N that doubles about every 5 days.
Does closing schools slow the spread of coronavirus? Past outbreaks provide clues
The Exponential Power of Now
Later I want to deconstruct the graph below, about ``flattening the curve''.
I also want to come back to an earlier post about epidemics on networks.
Footnote: The beginning quotation
"The greatest shortcoming of the human race is our inability to understand the exponential function."
is taken from a famous talk Arithmetic, population, and energy, by Al Bartlett, who was a Professor at University of Colorado.
The talk is based on Forgotten Fundamentals of the Energy Crisis, originally published in 1978 in the American Journal of Physics.
I first learned of Bartlett and his talk in the great movie, Two Raging Grannies.
Update. Henry Nourse brought to my attention an excellent article that gives a detailed analysis.
Coronavirus: Why You Must Act NowPoliticians, Community Leaders and Business Leaders: What Should You Do and When?
Tomas Pueyo
The most important graph is the one below. It makes the point that there is a fourteen-day lag between people having the virus and being diagnosed with it.
the orange bars show you what authorities knew, and the grey ones what was really happening.
On January 21st, the number of new diagnosed cases (orange) is exploding: there are around 100 new cases. In reality, there were 1,500 new cases that day, growing exponentially. But the authorities didn’t know that.
Many many US universities have now cancelled classes and sent undergraduate students home (with various variations of exactly how that has been done).
ReplyDeleteMultiple universities have also shutdown all research labs on campus (again, modulo minor differences in exactly how this is interpreted).
If your institution hasn't taken these steps already, the time to make a plan for your own department/research group/life is today: the period from when campus leaders start seriously contemplating drastic steps to things actually happening is typically very short.
I say us humans are good at understanding exponential growth when it suits us!
ReplyDeleteWe are used to seeing latest gadgets being 25-50% faster every year and are miffed when that doesn't happen. Too bad we can't think like that when it comes to negative phenomena like viruses or thermal runway of our climate
You are correct. Good point. Bankers and investors are particularly good at understanding exponential growth. It is also why economists can be obsessed with economic growth rates.
Deletehttps://www.pnas.org/content/113/11/3048
ReplyDeleteSARS-like WIV1-CoV poised for human emergence
https://www.nature.com/articles/nm.3985
A SARS-like cluster of circulating bat coronaviruses shows potential for human emergence.
All above papers in 2015.
https://www.ted.com/talks/bill_gates_the_next_outbreak_we_re_not_ready?language=en
The next outbreak we are not ready says Bill Gates with his intuitive pill in 2015.
The two papers talk about emergence and Gates talk hints at readiness for emergence. Since you have written time and again about emergence
What is your take on the above two papers and Gates talk . Is emergence of this pandemic exponential catalysed by thermodynamics like increase in entropy ( is it second law)
https://www.insidehook.com/daily_brief/history/how-isaac-newton-made-social-distancing-work-for-him
ReplyDeleteIsaac Newton did his great by social distancing.
"Newton's research in dynamics falls into three major periods: the plague years 1664-1666, the investigations of 1679-1680, following Hooke's correspondence, and the period 1684-1687, following Halley's visit to Cambridge. The gradual evolution of Newton's thought over these two decades illustrates the complexity of his achievement as well as the prolonged character of scientific 'discovery.'
DeleteWhile the myth of Newton and the apple maybe true, the traditional account of Newton and gravity is not"
Dr Robert A. Hatch - University of Florida
http://users.clas.ufl.edu/ufhatch/pages/01-courses/current-courses/08sr-newton.htm
People here in Sydney don't seem to be taking this seriously, e.g. crowds at Bondi beach, and a relatively full park I cycled by yesterday. It's easy math -- the current exponential growth (~ x1.25 everyday) here will lead to serious trouble the first/second week of April.
ReplyDelete